Comparative analysis of clinical characteristics and laboratory indicators of children with mixed bacterial and viral infections of Mycoplasma pneumoniae

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Methods A retrospective study included 392 children with MP infection, divided into MP mixed viral infection group (n = 254) and bacterial infection group (n = 138). Epidemiological characteristics, clinical manifestations, immune, coagulation, inflammatory indicators, pathogen distribution and bacterial drug susceptibility were compared. Results The viral group had older children [6 (3, 8) vs 4 (2, 6.25) years, P = 0.001], higher incidence in spring (51.97% vs 18.12%, P < 0.001), and more wet rales and decreased breath sounds ( P < 0.05). The bacterial group was more common in summer and autumn, with higher vomiting incidence ( P = 0.022), higher C3 abnormal rate ( P = 0.049) and more significant procalcitonin elevation ( P < 0.001). The viral group had higher serum amyloid A and D-dimer ( P < 0.05). Human rhinovirus was the predominant virus (53.67%), and Streptococcus pneumoniae was the main bacterium (58.99%) with 100% erythromycin resistance but high sensitivity to penicillin G and cefotaxime. Conclusions Differences exist in age, season, clinical and laboratory indicators between the two groups. Combined detection of procalcitonin, serum amyloid A and D-dimer aids early differentiation. Local pathogen spectrum and severe bacterial drug resistance require localized surveillance and rational antibiotic use. Children Mycoplasma pneumoniae Mixed infection Epidemiological characteristics Pathogen spectrum Laboratory indicators Figures Figure 1 1 Introduction Pneumonia is one of the leading causes of high morbidity and mortality among children under five years of age worldwide, and Mycoplasma pneumoniae (MP) is a common pathogen of community-acquired pneumonia in children [ 1 ] . MP infection not only causes pulmonary inflammation but also leads to a series of extrapulmonary complications. Severe cases may result in acute pulmonary embolism or multiple organ damage, among which refractory Mycoplasma pneumoniae pneumonia (MPP) has attracted increasing attention [ 2 – 5 ] . In recent years, studies have shown that MP infection follows a 3-5-year epidemic cycle, and its global infection rate increased in 2023 [ 6 ] , posing a severe challenge for prevention and control. The pathogenic mechanism of MP differs from that of conventional bacteria and viruses due to its lack of a cell wall. Co-infection of MP with viruses or bacteria is a key factor leading to aggravated disease conditions, prolonged courses, and complicated treatment. Co-infection may alter the body’s inflammatory response, coagulation function, and immune response patterns, which serve as important targets for clinical evaluation and intervention. Clarifying the specific changes and differences in coagulation function, immune function, and inflammatory indicators in children with MP co-infection with viruses or bacteria can compensate for the shortcomings of long turnaround time and limited positive rate in pediatric etiological detection, and provide a basis for early differential diagnosis. At present, although several studies have focused on MP co-infection [ 7 – 8 ] , systematic analyses of MP co-infection with different types of pathogens in children in Suzhou, especially comparative studies on clinical manifestations, immune status, coagulation function, and inflammatory response, remain insufficient due to significant regional and seasonal variations in the epidemic spectrum of pathogens. In this study, 392 children with MPP admitted to the Children’s Hospital of Soochow University from July 2021 to July 2023 were retrospectively enrolled. Clinical and laboratory data of children with MP infection in Suzhou were analyzed to: (1) clarify the epidemiological characteristics and pathogen spectrum of MP co-infection with viruses and bacteria in this region; (2) compare the differences in clinical characteristics and key laboratory indicators between the two infection groups; (3) explore laboratory marker combinations that can assist in identifying infection types; (4) analyze the drug resistance profiles of major co-infecting bacteria. This study aims to provide data support and theoretical evidence for early clinical differential diagnosis, empirical treatment, and localized prevention and control of respiratory tract infections. 2 Materials and Methods 2.1 Study Subjects Clinical data were retrospectively collected from children with MP infection hospitalized at the Children’s Hospital of Soochow University (CHSU) from July 2021 to July 2023. As the largest Grade A tertiary children’s specialized hospital in the region, CHSU admits relatively severe cases from Suzhou and surrounding areas. Therefore, the results of this study mainly reflect the epidemiological and clinical characteristics of MP co-infection among hospitalized children in this region. This study was approved by the Ethics Committee of the CHSU (Approval No.: 2025CS239), and the requirement for informed patient consent was waived. 2.2 Inclusion and Exclusion Criteria Inclusion criteria: (1) Age ranging from 1 month to 16 years; (2) Meeting the diagnostic criteria for MPP as defined in Zhu Futang Practical Pediatrics (8th edition) [ 9 ] and Guidelines for the Diagnosis and Treatment of Community-Acquired Pneumonia in Chinese Children (2023 Edition) [ 10 ] : presence of acute respiratory tract infection symptoms and radiological evidence of pneumonia, together with positive MP etiological test results (positive MP-DNA or MP-IgM); (3) Complete clinical data available. Exclusion criteria: (1) Pneumonia caused by foreign body aspiration; (2) Readmission for pneumonia within the past 1 month; (3) Complicated with congenital heart disease, primary immunodeficiency disease, or malignant tumor. 2.3 Grouping Method According to etiological test results, the children were divided into two groups: MP-virus co-infection group: On the basis of meeting MPP diagnostic criteria, at least one respiratory virus nucleic acid was detected by multiplex PCR in respiratory specimens. MP-bacteria co-infection group: On the basis of meeting MPP diagnostic criteria, a single dominant pathogenic bacterium was isolated from qualified sputum specimens with a clinically significant colony count (e.g., at least two quadrants positive by the four-quadrant streak plate method for sputum culture), and the isolate was judged as a pathogenic bacterium rather than colonizing or contaminating bacteria in combination with clinical manifestations. 2.4 Etiological Detection Methods 2.4.1 Nucleic Acid Detection of Viruses and Atypical Pathogens Nucleic acids were extracted using an automatic nucleic acid extraction system (Jiangsu Shuoshi Biological Technology Co., Ltd.). A 13-plex respiratory pathogen multiplex PCR detection kit (Ningbo Health Gene Technology Co., Ltd.) was used to detect nucleic acids of MP, human rhinovirus (HRV), respiratory syncytial virus (RSV), human parainfluenza virus (HPIV), human coronavirus (HCOV), human metapneumovirus (HMPV), human bocavirus (Boca), adenovirus (ADV), chlamydia (Ch), and influenza viruses (subtypes InfA H1N1, InfA H3N2, and InfB) on a 3500XL-Dx genetic analyzer. 2.4.2 Bacterial Culture, Identification and Drug Susceptibility Analysis Specimens were inoculated onto blood agar plates and chocolate agar plates (Zhengzhou Autobio Engineering Co., Ltd.) and incubated at 37 ℃ under 5% CO 2 for 24–48 hours. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (Bruker, Germany) was used for bacterial identification. Single colonies were picked directly from the plates for testing, and species-level identification results could be obtained within minutes, significantly optimizing the sputum culture and identification process. The reliability of identification was determined by confidence score (e.g., > 90%). Antimicrobial susceptibility testing was performed using the VITEK® 2 Compact automatic microbial analysis system (bioMérieux, France) and the Kirby-Bauer disk diffusion method. Results were interpreted according to the current standards of the Clinical and Laboratory Standards Institute (CLSI). Streptococcus pneumoniae (ATCC 49619) was used as the quality control strain, purchased from the National Center for Clinical Laboratories, National Health Commission of the People’s Republic of China. 2.4.3 Detection of MP-IgM Antibody Serum samples were collected and tested for MP-IgM antibody using a chemiluminescent immunoassay kit (Shenzhen YHLO Biotech Co., Ltd.) on an iFlash 3000 chemiluminescent analyzer. According to the manufacturer’s instructions, the kit had a sensitivity of ≥ 90% and specificity of ≥ 85%. A cut-off index (COI) ≥ 1.0 was defined as positive. 2.5 Statistical Methods SPSS 27.0 statistical software was used for data analysis. Normally distributed data were expressed as mean ± standard deviation and compared using independent-samples t-test. Non-normally distributed data were expressed as median (interquartile range, P25, P75) and compared using the Mann-Whitney U test. Categorical data were presented as n (%) and compared using the chi-square test. A two-sided P < 0.05 was considered statistically significant. 3 Results 3.1 Comparison of General Data and Clinical Characteristics A total of 392 children were enrolled, including 254 in the MP-virus co-infection group and 138 in the MP-bacteria co-infection group. Children in the virus co-infection group were significantly older than those in the bacterial co-infection group [6.0 (3.0, 8.0) years vs 4.0 (2.0, 6.3) years, P = 0.001]. A significant difference was observed in the distribution of onset seasons: the virus co-infection group peaked in spring (51.97%), while the bacterial co-infection group showed higher proportions in summer (33.33%) and autumn (34.78%) ( P < 0.001).Regarding clinical signs, the virus co-infection group had higher rates of moist rales (77.95% vs 67.39%) and decreased breath sounds (18.50% vs 7.25%, P < 0.05), whereas vomiting was more common in the bacterial co-infection group (30.43% vs 20.08%, P = 0.021). No significant differences were found between the two groups in gender, mode of delivery, past medical history, length of hospital stay, or duration of cough ( P > 0.05). See Table 1 . Table 1 Comparison of general data and clinical characteristics between the two groups [n (%), M (P25, P75)] Clinical characteristics MP-bacterial co-infection group (n = 138) MP-viral co-infection group (n = 254) Z/ χ2 P Hospital stay (days, IQR) 8 (7-9.25) 8 (7–10) -1.469 0.142 Cough duration (days, IQR) 7 (4–10) 6 (4–8) -0.879 0.379 Age (years, IQR) 4 (2-6.25) 6 (3–8) -3.298 0.001** Male, n (%) 62 (44.93) 109 (42.91) 0.148 0.701 Premature delivery, n (%) 128 (92.75) 242 (95.28) 1.074 0.300 Vaginal delivery, n (%) 90 (65.22) 167 (65.75) 0.011 0.916 History of pneumonia, n (%) 23 (16.67) 39 (15.35) 0.116 0.734 History of wheezing, n (%) 16 (11.59) 20 (7.87) 1.484 0.223 Onset season, n (%) Spring 25 (18.12) 132 (51.97) 42.679 < 0.001*** Summer 46 (33.33) 41 (16.14) 15.304 < 0.001*** Autumn 48 (34.78) 50 (19.69) 10.87 < 0.001*** Winter 19 (13.77) 31 (12.20) 0.196 0.658 Fever grade, n (%) Low fever ( 39℃) 69 (50) 135 (53.15) 0.355 0.551 Symptoms, n (%) Nasal congestion 50 (36.23) 105 (41.34) 0.975 0.323 Rhinorrhea 64 (46.38) 118 (46.46) 0 0.998 Three Depression Sign 9 (6.52) 8 (3.15) 2.451 0.117 Vomiting 42 (30.43) 51 (20.08) 5.299 0.021* Lung signs, n (%) Moist/rales 93 (67.39) 198 (77.95) 5.215 0.022* Wheezes/rales 42 (30.43) 72 (28.35) 0.189 0.664 Decreased breath sound 10 (7.25) 47 (18.50) 9.119 0.003** Radiological findings, n (%) Atelectasis 3 (2.17) 8 (3.15) 0.312 0.576 Pulmonary consolidation 5 (3.62) 16 (6.30) 1.263 0.261 Complications, n (%) Gastrointestinal dysfunction 9 (6.52) 29 (11.42) 2.448 0.118 Hypokalemia 10 (7.25) 28 (11.02) 1.457 0.227 Hyponatremia 5 (3.62) 7 (2.76) 0.227 0.634 Myocardial damage 3 (2.17) 5 (1.97) 0.019 0.891 Note: * P < 0.05, ** P < 0.01, *** P < 0.001. 2.2 Comparison of Immune Indicators The abnormal rate of complement C3 in the bacterial co-infection group (9.85%) was higher than that in the viral co-infection group (4.60%), with a statistically significant difference ( P = 0.049). There were no significant differences in other immune indicators (C4, immunoglobulins, lymphocyte subsets) between the two groups ( P > 0.05). See Table 2 . Table 2 Comparison and Analysis of Immune Function Lab test MP-bacterial co-infection group (n = 138) MP-viral co-infection group (n = 254) χ2 P C3 (> 1.8 g/L, 0.38 g/L, 2.22 g/L, 14.3 g/L, 2.08 g/L, 83%, 57%, 39%, 1.94%, 19%, 31%, 9.7%, < 3.8%) 52 (44.44) 114 (54.03) 2.766 0.096 Note: Some data were missing for certain indicators. Percentages shown in the table were calculated based on the number of patients who completed the corresponding tests. * P < 0.05. 2.3 Comparison of Coagulation Function The elevated rate of D-D in the viral co-infection group was higher than that in the bacterial co-infection group (44.96% vs 33.06%, P = 0.029), whereas the prolonged rate of APTT was lower than that in the bacterial co-infection group (72.80% vs 61.76%, P = 0.036). Details are shown in Table 3 . Table 3 Comparison and Analysis of Coagulation Function Lab test MP-bacterial co-infection group (n = 138) MP-viral co-infection group (n = 254) χ2 P PT (> 12.1 s) 114(91.20) 224(94.12) 1.088 0.297 APTT (> 36.5s) 91(72.80) 147(61.76) 4.421 0.036* Fib (> 3.5g/L) 106(84.80) 207(86.97) 0.326 0.568 TT (> 21s) 0 1(0.42) 0.527 0.468 AT-III (> 120%, 550ug/L) 41(33.06) 107(44.96) 4.771 0.029* FDP (> 5000ug/L) 5(9.26) 13(7.10) 0.276 0.599 Note: Prothrombin Time (PT); Activated Partial Thromboplastin Time (APTT); Fibrinogen (Fib); Thrombin Time (TT); Antithrombin III (AT-III); D-dimer (D-D); Fibrin Degradation Products (FDP). Some data were missing for certain indicators. Percentages shown in the table were calculated based on the number of patients who completed the corresponding tests. * P < 0.05. 2.4 Comparison of Inflammatory Indicators The elevated rate of procalcitonin (PCT) in the bacterial co-infection group (20.99%) was significantly higher than that in the viral co-infection group (5.68%, P < 0.001). In contrast, the elevated rate of serum amyloid A (SAA) in the viral co-infection group (94.29%) was significantly higher than that in the bacterial co-infection group (68.57%, P = 0.006). No significant differences were observed in the abnormal rates of heparin-binding protein (HBP) and C-reactive protein (CRP) between the two groups ( P > 0.05). See Table 4 . Table 4 Comparison and Analysis of Inflammatory Indicators Lab test MP-bacterial co-infection group (n = 138) MP-viral co-infection group (n = 254) χ2 P PCT (> 0.5 ng/mL) 17 (20.99) 10 (5.68) 13.821 10 mg/L) 24 (68.57) 33 (94.29) 7.652 0.006** HBP (> 11.4 ng/mL) 52 (86.67) 56 (84.85) 0.085 0.771 sCRP (> 8 mg/L) 83 (61.03) 135 (54.22) 1.662 0.197 Note: Some data were missing for certain indicators. Percentages shown in the table were calculated based on the number of patients who completed the corresponding tests. **P < 0.01, *** P < 0.001. 2.5 Analysis of Viral Spectrum A total of 300 virus strains were detected in children with viral co-infection. (HRV showed the highest constituent ratio (53.67%, 161/300) and was the predominant virus in spring and summer, followed by HCOV (11.67%) and RSV (11.00%). Details are presented in Table 5 . Table 5 Analysis of Detected Viruses in Different Seasons Virus Spring (n) Summer (n) Autumn (n) Winter (n) Total (n) HRV 41 61 36 23 161 HCOV 7 18 10 0 35 HRSV 8 10 12 3 33 HPIV 5 12 10 2 29 HMPV 5 5 2 1 13 Boca 3 2 6 1 12 InfA H3N2 2 1 2 1 6 ADV 0 2 2 0 4 Ch 1 2 0 0 3 InfA H1N1 2 0 1 0 3 Infb 0 1 0 0 1 Total 74 114 81 31 300 2.6 Analysis of Viral Co-infection Patterns Analysis of viral co-infection patterns: MP co-infection with a single virus was the main pattern (85.00%, 254/299), dual viral co-infection accounted for 11.00%, and triple viral co-infection accounted for 4.00%. Common viral combinations included HRV/HPIV and HRV/RSV, as shown in Fig. 1 . 2.7 Annual Composition of Bacterial Spectrum A total of 139 bacterial strains were isolated from 138 children with bacterial co-infection, among which Gram-positive bacteria accounted for 75.54%. Streptococcus pneumoniae was the absolute dominant pathogen, accounting for 58.99% (82/139), followed by Haemophilus influenzae (24/139, 17.27%) and Staphylococcus aureus (23/139, 16.55%). See Table 6 . Table 6 Annual Distribution of Bacterial Strains. Co-infecting Bacteria No. of Strains (n) 2021 2022 2023 Percentage (%) Streptococcus pneumoniae 82 34 25 23 58.99 Haemophilus influenzae 24 8 7 9 17.27 Staphylococcus aureus 23 3 12 8 16.55 Moraxella catarrhalis 5 0 3 2 3.60 Klebsiella pneumoniae 2 0 1 1 1.44 Acinetobacter baumanni 1 .0 1 0 0.72 Stenotrophomonas maltophilia 1 0 0 1 0.72 Pseudomonas aeruginosa 1 1 0 0 0.72 Total 139 46 49 44 100 2.8 Drug Susceptibility Results of Streptococcus pneumoniae Streptococcus pneumoniae was the major pathogen, with 82 strains isolated in total. Among them, 68 strains were dominant strains in pure culture from qualified sputum samples and were included in the final analysis of drug susceptibility results; the remaining 14 strains failed to complete full-set drug susceptibility testing due to culture conditions or specimen quality issues. As shown in Table 7 , the drug resistance rate to erythromycin (macrolide antibiotic) was as high as 100.00%. The resistance rate of Streptococcus pneumoniae to tetracycline was above 80% from 2021 to 2022 and decreased in 2023. However, the susceptibility rates to penicillin G, cefotaxime and chloramphenicol remained at 84.75%, 90.32% and 92.65%, respectively, and 100.00% susceptibility was observed to rifampicin, linezolid, levofloxacin, vancomycin and other agents. Table 7 Analysis of Drug Susceptibility Results of Streptococcus pneumoniae Antimicrobial Agents 2021 (n = 34) 2022 (n = 13) 2023 (n = 21) No. of Resistant Strains (n) Resistance Rate (%) No. of Resistant Strains (n) Resistance Rate (%) No. of Resistant Strains (n) Resistance Rate (%) Erythromycin 34 100 13 100 21 100 Clindamycin 34 100 13 100 - - Tetracycline 29 85.29 11 84.62 19 90.48 Sulfamethoxazole-trimethoprim 27 79.41 11 84.62 13 61.90 Quinupristin/dalfopristin 21 61.76 11 84.62 - - Penicillin G 0 0 0 0 1 4.76 Cefotaxime 4 11.76 5 38.46 3 14.29 Chloramphenicol 3 8.82 1 7.69 1 4.76 Rifampicin 0 0 0 0 - - Linezolid 0 0 0 0 - - Levofloxacin 0 0 0 0 0 0 Vancomycin 0 0 0 0 0 0 Amoxicillin 4 11.76 5 6 28.57 Moxifloxacin 0 0 0 0 0 0 Note: “-” indicates that the corresponding antibiotic was not tested. 4 Discussion MPP is the leading cause of community-acquired pneumonia (CAP) in children aged 3–15 years [ 1 ] . Co-infection with viruses or bacteria has become a key factor exacerbating disease severity and complicating clinical management. Compared with single MPP infection, co-infection is associated with more severe clinical symptoms and a higher incidence of complications [ 12 – 13 ] . Given the regional and seasonal variations in the pathogen spectrum of MPP co-infections, larger-sample epidemiological and mechanistic studies are urgently needed to guide clinical practice. This study compared the clinical characteristics, immune, coagulation, and inflammatory indicators between children with MP plus viral co-infection and those with MP plus bacterial co-infection, providing a basis for clinical differentiation and treatment. Children in the MP plus viral co-infection group were older, consistent with the immune developmental characteristics that older children have a wider range of activities and higher risk of viral exposure, whereas younger children have immature immune systems and are more susceptible to secondary bacterial infections [ 14 ] . The significant difference in onset seasons provides preliminary clues for clinical suspected diagnosis across seasons (viral infections peaked in spring, while bacterial infections predominated in summer and autumn). This may be related to increased viral activity and variable climate in spring, which reduce respiratory mucosal resistance, as well as suitable temperatures for bacterial proliferation in summer and autumn. These findings are consistent with those reported by Ge et al. in 2025, who noted a peak of MP plus viral coinfection in spring [ 15 ] . Regarding symptoms and pulmonary signs, the incidence of vomiting was higher in the MP plus bacterial co-infection group, while moist rales and decreased breath sounds were more common in the MP plus viral co-infection group. Viral infections may more readily induce increased airway secretions and impaired pulmonary ventilation, consistent with the pathological mechanism of viral invasion into respiratory epithelial cells, causing mucosal inflammation and edema [ 14 ] . In clinical practice, age, onset season, and core symptoms can be used to preliminarily determine the infection type, providing a reference for early intervention. Based on identified differences in clinical characteristics, we further analyzed the immune status of the two groups. The results showed a higher abnormal rate of complement C3 in the MP plus bacterial co-infection group, suggesting that early bacterial infection may activate the complement system via the classical or alternative pathway, participating in pathogen clearance and inflammatory responses. Abnormal elevation or reduction of C3 may reflect stronger immune activation induced by bacterial infection [ 16 ] . However, there were no significant differences in immunoglobulins or T lymphocyte subsets between the two groups. This may be because MP infection itself has already exerted certain effects on the children’s immune function, masking the specific immune differences between bacterial and viral coinfections. It also indicates that changes in immune function during MP coinfection may be more closely related to MP itself rather than the type of secondary pathogen. Coagulation dysfunction is a common manifestation of MPP, and its mechanism is associated with MP-induced cytokine release, vascular injury, and increased thrombotic risk [ 17 ] . In this study, the rate of prolonged APTT was higher in the bacterial co-infection group, which may be related to direct endothelial cell damage and activation of the intrinsic coagulation pathway by bacteria. In contrast, D-D elevation was more significant in the viral co-infection group, suggesting that viral infection is more likely to trigger systemic inflammatory responses and fibrinolytic system activation, increasing the risk of thrombosis. Previous studies have identified D-D as an independent risk factor for thrombosis [ 18 ] . Close monitoring and intervention of coagulation function are clinically necessary for such children to prevent thrombotic complications. Among inflammatory indicators, PCT and SAA showed core differential diagnostic value. PCT was significantly elevated in bacterial infections but not obviously increased in viral infections, consistent with previous studies reporting the high specificity of PCT for bacterial infection [ 19 – 20 ] . The sensitivity of SAA in viral infections reached 94.29%, significantly higher than that in the bacterial infection group, in line with the characteristic rapid early elevation of SAA in viral infections [ 21 ] . No significant differences were observed in serum levels of HBP and CRP between the two groups ( P > 0.05). PCT showed high specificity for identifying concurrent bacterial infection, while SAA exhibited high sensitivity for indicating concurrent viral infection. Combined detection of the two markers is complementary, providing key references for early differentiation and initial treatment decisions before pathogen results are available. Regarding the viral spectrum, single viral co-infection with MP was the most common pattern, and co-infection with two or more viruses was also not uncommon, suggesting that multiplex pathogen detection should be emphasized in children with MP infection. HRV was the predominant virus in the Suzhou area, consistent with previous findings [ 22 ] . However, marked regional differences exist in the predominant viral spectrum compared with Beijing, Liaoning in China, and Russia abroad [ 23 – 24 ] . These differences may stem from climatic conditions in East China, immune backgrounds of the pediatric population, and local epidemic strains of pathogens, highlighting that respiratory pathogen surveillance must be localized and clinical experience cannot be simply applied across regions. Among bacterial isolates, the top three pathogens were Streptococcus pneumoniae , Haemophilus influenzae , and Staphylococcus aureus , consistent with the distribution of common pathogens causing community-acquired pneumonia [ 26 – 27 ] . Drug susceptibility analysis of 68 Streptococcus pneumoniae strains (34 in 2021, 13 in 2022, 21 in 2023) revealed: Resistance rate to erythromycin remained 100% from 2021 to 2023; Resistance rate to clindamycin was 100% in 2021–2022 (not tested in 2023); Tetracycline resistance increased from 85.29% (2021) to 90.48% (2023); Resistance rate to compound sulfamethoxazole decreased from 79.41% (2021) and 84.62% (2022) to 29.42% (2023); Among β-lactams, penicillin G remained 100% sensitive over the three years; Cefotaxime resistance rose from 11.76% (2021) to 38.46% (2022) and fell to 14.29% (2023); Amoxicillin resistance increased from 11.76% (2021) to 28.57% (2023); Levofloxacin, moxifloxacin, vancomycin, and linezolid showed 100% susceptibility. These findings provide important references for empirical antimicrobial therapy. For children highly suspected of MP plus bacterial co-infection, especially co-infection with Streptococcus pneumoniae, monotherapy with highly resistant agents such as macrolides should be avoided. β-lactam antibiotics may be preferred, and third-generation cephalosporins or other sensitive agents can be used if the response is poor, so as to prevent antibiotic abuse. In conclusion, differences exist between children with MP plus bacterial coinfection and those with viral co-infection in age, onset season, clinical symptoms, immune function, coagulation function, and inflammatory indicators. Combined detection of PCT, SAA, D-D and other markers facilitates early differentiation of infection types. This study is a retrospective single-center analysis including only hospitalized children, without coverage of outpatients with mild disease, which may lead to selection bias. Long-term follow-up of prognosis and treatment efficacy was not performed. Future multicenter and prospective studies incorporating comprehensive pathogen detection techniques such as metagenomic next-generation sequencing are warranted to further clarify the dynamic changes of co-infection, pathogen interactions, and their impacts on prognosis, so as to provide higher-level evidence for the development of individualized treatment and prevention strategies. Declarations Ethics and consent to participate The project is a retrospective study of data and only includes specific data. It was reviewed and approved by the Medical Ethics Committee of the Children's Hospital of Soochow University (Ethics batch number: 2025CS239). Consent for publication Not applicable. This manuscript does not contain any individual person’s data in any form (including individual details, images or videos). Availability of Data and Materials The datasets used and/or analysed during the current study available from the corresponding author on reasonable request. Conflicts of interest All other authors report no potential conflicts of interest. Funding support Suzhou Municipal Health Commission (KJXW2023025), Guided Project of Jiangsu Provincial Natural Science Foundation (Z2025037). Author contributions YX Z and Y J conceived the study and designed the experiments. X Z provide financial support and collected the data. YX Z and Y J analysed the data and interpreted the results. YX Z and Y J drafted the manuscript, and all authors critically revised the manuscript for intellectual content, and read and approved the final manuscript. Acknowledgments We thank the staff from the Department of Clinical Laboratory, Children's Hospital of Soochow University , who took part in the study. References Diaz MH, Hersh AL, Olson J, et al. 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Sarathchandran P, Al Madani A, Alboudi AM et al. Mycoplasma pneumoniae infection presenting as stroke and meningoencephalitis with aortic and subclavian aneurysms without pulmonary involvement[J]. BMJ Case Rep. 2018, 2017221831. Mirijello A, La Marca A, D'Errico MM, et al. Venous thromboembolism during Mycoplasma pneumoniae infection: case report and review of the literature[J]. Eur Rev Med Pharmacol Sci. 2020;24(19):10061–8. Qian Y, Gong M, Xie HQ, et al. Etiological characteristics of pediatric pneumonia and serum levels of CRP, IL-10 and PCT[J]. Chin J Nosocomiology. 2025;35(09):1357–61. Tan LK, Luo MN, Xie GM, et al. Early diagnostic value of combined detection of IL-6, SAA, CRP and PCT in patients with Mycoplasma pneumoniae complicated by bacterial infection[J]. Chin J Mod Drug Application. 2024;18(8):66–9. Li Yigang Z, hs-CRP B. WBC and SAA/hs-CRP ratio in children with respiratory viral infectious diseases[J]. Journal of Hunan Normal University (Medical Science), 2022, 19(02): 67–70. Yuan L, Mingyue D, Zhou L. Analysis of the characteristics of mixed infections with Mycoplasma pneumoniae in children[J]. Sci Rep. 2025;15(1):9414–20. Sun Y, Zhu R, Wang F. etc Analysis of the pathogenic spectrum of acute respiratory infections in children in Beijing in spring 2023[J]. Chin J Pediatr. 2024;62(2):159–64. Yu A, Ran L, Sun X, Feng T. Significance of respiratory virus coinfection in children with Mycoplasma pneumoniae pneumonia[J]. BMC Pulm Med. 2024;24(1):585–93. Korneenko E, Rog I, Chudinov I, et al. Antibiotic resistance and viral co-infection in children diagnosed with pneumonia caused by Mycoplasma pneumoniae admitted to Russian hospitals during October 2023-February 2024[J]. BMC Infect Dis. 2025;25(1):363–78. Meyer Sauteur PM. Childhood community-acquired pneumonia[J]. Eur J Pediatr. 2024;183(3):1129–36. Song Q, Xu BP, Shen KL. Effects of bacterial and viral co-infections of mycoplasma pneumoniae pneumonia in children: analysis report from Beijing Children's Hospital between 2010 and 2014[J]. Int J Clin Exp Med. 2015;8(9):15666–74. Cite Share Download PDF Status: Under Revision Version 1 posted Editorial decision: Major revision 12 May, 2026 Reviewers agreed at journal 29 Apr, 2026 Reviewers invited by journal 29 Apr, 2026 Editor assigned by journal 18 Apr, 2026 First submitted to journal 17 Apr, 2026 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-9446289","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":631816630,"identity":"cf79b15e-f5cf-42c6-8884-e6ba7f81f7d4","order_by":0,"name":"Yixin Zhu","email":"","orcid":"","institution":"Children's Hospital of Soochow University","correspondingAuthor":false,"prefix":"","firstName":"Yixin","middleName":"","lastName":"Zhu","suffix":""},{"id":631816631,"identity":"bd53215d-211a-4e56-b5d6-8007943b9fb9","order_by":1,"name":"Xin Zhang","email":"","orcid":"","institution":"Children's Hospital of Soochow University","correspondingAuthor":false,"prefix":"","firstName":"Xin","middleName":"","lastName":"Zhang","suffix":""},{"id":631816632,"identity":"4e104fd5-aa02-4b6e-a80f-963a7087a8c4","order_by":2,"name":"Ying Jin","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAvklEQVRIiWNgGAWjYBACNmbmww8kKmrs5NkbiNTCx96WZmBx5liyYc8BIrXI8ZxRkKhsY2ZsuJFArMMkchgMbrCxMTPOfLzxBkONTTQRWnIPPJzBI8PHLp1WbMFwLC23gbCWvARjCQmgLbNzzCQYGw4ToyXHQPqPAdAvN88Qq4XnjIGERALI+zzEagEFssQBUCAD/ZJAjF/km4FRKfkPFJWHN974UGNDWAsyMJBIIEU5RAupOkbBKBgFo2BkAABbITry79aXzAAAAABJRU5ErkJggg==","orcid":"","institution":"Children's Hospital of Soochow University","correspondingAuthor":true,"prefix":"","firstName":"Ying","middleName":"","lastName":"Jin","suffix":""}],"badges":[],"createdAt":"2026-04-17 08:29:45","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-9446289/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-9446289/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":108957249,"identity":"d1c0d285-a646-44c4-af97-d6a43e6eeae3","added_by":"auto","created_at":"2026-05-11 08:17:29","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":854087,"visible":true,"origin":"","legend":"\u003cp\u003eAnalysis of Viral Co-infection Patterns\u003c/p\u003e","description":"","filename":"Figure1.png","url":"https://assets-eu.researchsquare.com/files/rs-9446289/v1/d7652a929b4e8e36f98c6945.png"},{"id":108957253,"identity":"b60321af-bd9e-454d-8f62-3ea942d0b496","added_by":"auto","created_at":"2026-05-11 08:17:34","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1327846,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-9446289/v1/df1abc98-1208-4e04-906c-b397fc864e40.pdf"}],"financialInterests":"","formattedTitle":"\u003cp\u003eComparative analysis of clinical characteristics and laboratory indicators of children with mixed bacterial and viral infections of \u003cem\u003eMycoplasma pneumoniae\u003c/em\u003e\u003c/p\u003e","fulltext":[{"header":"1 Introduction","content":"\u003cp\u003ePneumonia is one of the leading causes of high morbidity and mortality among children under five years of age worldwide, and \u003cem\u003eMycoplasma pneumoniae\u003c/em\u003e (MP) is a common pathogen of community-acquired pneumonia in children\u003csup\u003e[\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]\u003c/sup\u003e. MP infection not only causes pulmonary inflammation but also leads to a series of extrapulmonary complications. Severe cases may result in acute pulmonary embolism or multiple organ damage, among which refractory Mycoplasma pneumoniae pneumonia (MPP) has attracted increasing attention\u003csup\u003e[\u003cspan additionalcitationids=\"CR3 CR4\" citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]\u003c/sup\u003e. In recent years, studies have shown that MP infection follows a 3-5-year epidemic cycle, and its global infection rate increased in 2023\u003csup\u003e[\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e]\u003c/sup\u003e, posing a severe challenge for prevention and control. The pathogenic mechanism of MP differs from that of conventional bacteria and viruses due to its lack of a cell wall. Co-infection of MP with viruses or bacteria is a key factor leading to aggravated disease conditions, prolonged courses, and complicated treatment. Co-infection may alter the body\u0026rsquo;s inflammatory response, coagulation function, and immune response patterns, which serve as important targets for clinical evaluation and intervention. Clarifying the specific changes and differences in coagulation function, immune function, and inflammatory indicators in children with MP co-infection with viruses or bacteria can compensate for the shortcomings of long turnaround time and limited positive rate in pediatric etiological detection, and provide a basis for early differential diagnosis. At present, although several studies have focused on MP co-infection\u003csup\u003e[\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]\u003c/sup\u003e, systematic analyses of MP co-infection with different types of pathogens in children in Suzhou, especially comparative studies on clinical manifestations, immune status, coagulation function, and inflammatory response, remain insufficient due to significant regional and seasonal variations in the epidemic spectrum of pathogens.\u003c/p\u003e \u003cp\u003eIn this study, 392 children with MPP admitted to the \u003cem\u003eChildren\u0026rsquo;s Hospital of Soochow University\u003c/em\u003e from July 2021 to July 2023 were retrospectively enrolled. Clinical and laboratory data of children with MP infection in Suzhou were analyzed to: (1) clarify the epidemiological characteristics and pathogen spectrum of MP co-infection with viruses and bacteria in this region; (2) compare the differences in clinical characteristics and key laboratory indicators between the two infection groups; (3) explore laboratory marker combinations that can assist in identifying infection types; (4) analyze the drug resistance profiles of major co-infecting bacteria. This study aims to provide data support and theoretical evidence for early clinical differential diagnosis, empirical treatment, and localized prevention and control of respiratory tract infections.\u003c/p\u003e"},{"header":"2 Materials and Methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003e2.1 Study Subjects\u003c/h2\u003e \u003cp\u003eClinical data were retrospectively collected from children with MP infection hospitalized at the \u003cem\u003eChildren\u0026rsquo;s Hospital of Soochow University\u003c/em\u003e (CHSU) from July 2021 to July 2023. As the largest Grade A tertiary children\u0026rsquo;s specialized hospital in the region, CHSU admits relatively severe cases from Suzhou and surrounding areas. Therefore, the results of this study mainly reflect the epidemiological and clinical characteristics of MP co-infection among hospitalized children in this region. This study was approved by the Ethics Committee of the CHSU (Approval No.: 2025CS239), and the requirement for informed patient consent was waived.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec4\" class=\"Section2\"\u003e \u003ch2\u003e2.2 Inclusion and Exclusion Criteria\u003c/h2\u003e \u003cp\u003eInclusion criteria: (1) Age ranging from 1 month to 16 years; (2) Meeting the diagnostic criteria for MPP as defined in \u003cem\u003eZhu Futang Practical Pediatrics (8th edition)\u003c/em\u003e\u003csup\u003e[\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e]\u003c/sup\u003e and Guidelines for the Diagnosis and Treatment of Community-Acquired Pneumonia in Chinese Children (2023 Edition)\u003csup\u003e[\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]\u003c/sup\u003e: presence of acute respiratory tract infection symptoms and radiological evidence of pneumonia, together with positive MP etiological test results (positive MP-DNA or MP-IgM); (3) Complete clinical data available.\u003c/p\u003e \u003cp\u003eExclusion criteria: (1) Pneumonia caused by foreign body aspiration; (2) Readmission for pneumonia within the past 1 month; (3) Complicated with congenital heart disease, primary immunodeficiency disease, or malignant tumor.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec5\" class=\"Section2\"\u003e \u003ch2\u003e2.3 Grouping Method\u003c/h2\u003e \u003cp\u003eAccording to etiological test results, the children were divided into two groups: MP-virus co-infection group: On the basis of meeting MPP diagnostic criteria, at least one respiratory virus nucleic acid was detected by multiplex PCR in respiratory specimens. MP-bacteria co-infection group: On the basis of meeting MPP diagnostic criteria, a single dominant pathogenic bacterium was isolated from qualified sputum specimens with a clinically significant colony count (e.g., at least two quadrants positive by the four-quadrant streak plate method for sputum culture), and the isolate was judged as a pathogenic bacterium rather than colonizing or contaminating bacteria in combination with clinical manifestations.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec6\" class=\"Section2\"\u003e \u003ch2\u003e2.4 Etiological Detection Methods\u003c/h2\u003e \u003cdiv id=\"Sec7\" class=\"Section3\"\u003e \u003ch2\u003e2.4.1 Nucleic Acid Detection of Viruses and Atypical Pathogens\u003c/h2\u003e \u003cp\u003eNucleic acids were extracted using an automatic nucleic acid extraction system (Jiangsu Shuoshi Biological Technology Co., Ltd.). A 13-plex respiratory pathogen multiplex PCR detection kit (Ningbo Health Gene Technology Co., Ltd.) was used to detect nucleic acids of MP, \u003cem\u003ehuman rhinovirus\u003c/em\u003e (HRV), \u003cem\u003erespiratory syncytial virus\u003c/em\u003e (RSV), \u003cem\u003ehuman parainfluenza virus\u003c/em\u003e (HPIV), \u003cem\u003ehuman coronavirus\u003c/em\u003e (HCOV), \u003cem\u003ehuman metapneumovirus\u003c/em\u003e (HMPV), \u003cem\u003ehuman bocavirus\u003c/em\u003e (Boca), \u003cem\u003eadenovirus\u003c/em\u003e (ADV), \u003cem\u003echlamydia\u003c/em\u003e (Ch), and influenza viruses (subtypes InfA H1N1, InfA H3N2, and InfB) on a 3500XL-Dx genetic analyzer.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec8\" class=\"Section3\"\u003e \u003ch2\u003e2.4.2 Bacterial Culture, Identification and Drug Susceptibility Analysis\u003c/h2\u003e \u003cp\u003eSpecimens were inoculated onto blood agar plates and chocolate agar plates (Zhengzhou Autobio Engineering Co., Ltd.) and incubated at 37 ℃ under 5% CO\u003csub\u003e2\u003c/sub\u003e for 24\u0026ndash;48 hours. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (Bruker, Germany) was used for bacterial identification. Single colonies were picked directly from the plates for testing, and species-level identification results could be obtained within minutes, significantly optimizing the sputum culture and identification process. The reliability of identification was determined by confidence score (e.g., \u0026gt; 90%). Antimicrobial susceptibility testing was performed using the VITEK\u0026reg; 2 Compact automatic microbial analysis system (bioM\u0026eacute;rieux, France) and the Kirby-Bauer disk diffusion method. Results were interpreted according to the current standards of the Clinical and Laboratory Standards Institute (CLSI). \u003cem\u003eStreptococcus pneumoniae\u003c/em\u003e (ATCC 49619) was used as the quality control strain, purchased from the National Center for Clinical Laboratories, National Health Commission of the People\u0026rsquo;s Republic of China.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec9\" class=\"Section3\"\u003e \u003ch2\u003e2.4.3 Detection of MP-IgM Antibody\u003c/h2\u003e \u003cp\u003eSerum samples were collected and tested for MP-IgM antibody using a chemiluminescent immunoassay kit (Shenzhen YHLO Biotech Co., Ltd.) on an iFlash 3000 chemiluminescent analyzer. According to the manufacturer\u0026rsquo;s instructions, the kit had a sensitivity of \u0026ge;\u0026thinsp;90% and specificity of \u0026ge;\u0026thinsp;85%. A cut-off index (COI)\u0026thinsp;\u0026ge;\u0026thinsp;1.0 was defined as positive.\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv id=\"Sec10\" class=\"Section2\"\u003e \u003ch2\u003e2.5 Statistical Methods\u003c/h2\u003e \u003cp\u003eSPSS 27.0 statistical software was used for data analysis. Normally distributed data were expressed as mean\u0026thinsp;\u0026plusmn;\u0026thinsp;standard deviation and compared using independent-samples t-test. Non-normally distributed data were expressed as median (interquartile range, P25, P75) and compared using the Mann-Whitney U test. Categorical data were presented as n (%) and compared using the chi-square test. A two-sided \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05 was considered statistically significant.\u003c/p\u003e \u003c/div\u003e"},{"header":"3 Results","content":"\u003cdiv id=\"Sec12\" class=\"Section2\"\u003e\n \u003ch2\u003e3.1 Comparison of General Data and Clinical Characteristics\u003c/h2\u003e\n \u003cp\u003eA total of 392 children were enrolled, including 254 in the MP-virus co-infection group and 138 in the MP-bacteria co-infection group. Children in the virus co-infection group were significantly older than those in the bacterial co-infection group [6.0 (3.0, 8.0) years vs 4.0 (2.0, 6.3) years, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.001]. A significant difference was observed in the distribution of onset seasons: the virus co-infection group peaked in spring (51.97%), while the bacterial co-infection group showed higher proportions in summer (33.33%) and autumn (34.78%) (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.001).Regarding clinical signs, the virus co-infection group had higher rates of moist rales (77.95% vs 67.39%) and decreased breath sounds (18.50% vs 7.25%, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05), whereas vomiting was more common in the bacterial co-infection group (30.43% vs 20.08%, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.021). No significant differences were found between the two groups in gender, mode of delivery, past medical history, length of hospital stay, or duration of cough (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026gt;\u0026thinsp;0.05). See Table \u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e1\u003c/span\u003e.\u003c/p\u003e\n \u003cdiv class=\"gridtable\"\u003e\u0026nbsp;\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003eComparison of general data and clinical characteristics between the two groups [n (%), M (P25, P75)]\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003ccolgroup cols=\"5\"\u003e\u003c/colgroup\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eClinical characteristics\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colname=\"c2\"\u003e\n \u003cp\u003eMP-bacterial co-infection group (n\u0026thinsp;=\u0026thinsp;138)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colname=\"c3\"\u003e\n \u003cp\u003eMP-viral co-infection group (n\u0026thinsp;=\u0026thinsp;254)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colname=\"c4\"\u003e\n \u003cp\u003e\u003cem\u003eZ/\u003c/em\u003e\u0026chi;2\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colname=\"c5\"\u003e\n \u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eHospital stay (days, IQR)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c2\"\u003e\n \u003cp\u003e8 (7-9.25)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c3\"\u003e\n \u003cp\u003e8 (7\u0026ndash;10)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c4\"\u003e\n \u003cp\u003e-1.469\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\n \u003cp\u003e0.142\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eCough duration (days, IQR)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c2\"\u003e\n \u003cp\u003e7 (4\u0026ndash;10)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c3\"\u003e\n \u003cp\u003e6 (4\u0026ndash;8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c4\"\u003e\n \u003cp\u003e-0.879\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\n \u003cp\u003e0.379\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eAge (years, IQR)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c2\"\u003e\n \u003cp\u003e4 (2-6.25)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c3\"\u003e\n \u003cp\u003e6 (3\u0026ndash;8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c4\"\u003e\n \u003cp\u003e-3.298\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\n \u003cp\u003e0.001**\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eMale, n (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c2\"\u003e\n \u003cp\u003e62 (44.93)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c3\"\u003e\n \u003cp\u003e109 (42.91)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c4\"\u003e\n \u003cp\u003e0.148\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\n \u003cp\u003e0.701\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003ePremature delivery, n (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c2\"\u003e\n \u003cp\u003e128 (92.75)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c3\"\u003e\n \u003cp\u003e242 (95.28)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c4\"\u003e\n \u003cp\u003e1.074\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\n \u003cp\u003e0.300\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eVaginal delivery, n (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c2\"\u003e\n \u003cp\u003e90 (65.22)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c3\"\u003e\n \u003cp\u003e167 (65.75)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c4\"\u003e\n \u003cp\u003e0.011\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\n \u003cp\u003e0.916\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eHistory of pneumonia, n (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c2\"\u003e\n \u003cp\u003e23 (16.67)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c3\"\u003e\n \u003cp\u003e39 (15.35)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c4\"\u003e\n \u003cp\u003e0.116\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\n \u003cp\u003e0.734\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eHistory of wheezing, n (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c2\"\u003e\n \u003cp\u003e16 (11.59)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c3\"\u003e\n \u003cp\u003e20 (7.87)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c4\"\u003e\n \u003cp\u003e1.484\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\n \u003cp\u003e0.223\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eOnset season, n (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eSpring\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c2\"\u003e\n \u003cp\u003e25 (18.12)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c3\"\u003e\n \u003cp\u003e132 (51.97)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c4\"\u003e\n \u003cp\u003e42.679\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\n \u003cp\u003e\u0026lt;\u0026thinsp;0.001***\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eSummer\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c2\"\u003e\n \u003cp\u003e46 (33.33)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c3\"\u003e\n \u003cp\u003e41 (16.14)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c4\"\u003e\n \u003cp\u003e15.304\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\n \u003cp\u003e\u0026lt;\u0026thinsp;0.001***\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eAutumn\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c2\"\u003e\n \u003cp\u003e48 (34.78)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c3\"\u003e\n \u003cp\u003e50 (19.69)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c4\"\u003e\n \u003cp\u003e10.87\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\n \u003cp\u003e\u0026lt;\u0026thinsp;0.001***\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eWinter\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c2\"\u003e\n \u003cp\u003e19 (13.77)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c3\"\u003e\n \u003cp\u003e31 (12.20)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c4\"\u003e\n \u003cp\u003e0.196\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\n \u003cp\u003e0.658\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eFever grade, n (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eLow fever (\u0026lt;\u0026thinsp;38℃)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c2\"\u003e\n \u003cp\u003e9 (6.52)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c3\"\u003e\n \u003cp\u003e9 (3.54)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c4\"\u003e\n \u003cp\u003e1.811\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\n \u003cp\u003e0.178\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eModerate fever (38\u0026ndash;39℃)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c2\"\u003e\n \u003cp\u003e44 (31.88)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c3\"\u003e\n \u003cp\u003e89 (35.04)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c4\"\u003e\n \u003cp\u003e0.397\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\n \u003cp\u003e0.529\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eHigh fever (\u0026gt;\u0026thinsp;39℃)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c2\"\u003e\n \u003cp\u003e69 (50)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c3\"\u003e\n \u003cp\u003e135 (53.15)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c4\"\u003e\n \u003cp\u003e0.355\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\n \u003cp\u003e0.551\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eSymptoms, n (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eNasal congestion\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c2\"\u003e\n \u003cp\u003e50 (36.23)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c3\"\u003e\n \u003cp\u003e105 (41.34)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c4\"\u003e\n \u003cp\u003e0.975\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\n \u003cp\u003e0.323\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eRhinorrhea\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c2\"\u003e\n \u003cp\u003e64 (46.38)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c3\"\u003e\n \u003cp\u003e118 (46.46)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c4\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\n \u003cp\u003e0.998\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eThree Depression Sign\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c2\"\u003e\n \u003cp\u003e9 (6.52)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c3\"\u003e\n \u003cp\u003e8 (3.15)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c4\"\u003e\n \u003cp\u003e2.451\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\n \u003cp\u003e0.117\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eVomiting\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c2\"\u003e\n \u003cp\u003e42 (30.43)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c3\"\u003e\n \u003cp\u003e51 (20.08)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c4\"\u003e\n \u003cp\u003e5.299\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\n \u003cp\u003e0.021*\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eLung signs, n (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eMoist/rales\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c2\"\u003e\n \u003cp\u003e93 (67.39)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c3\"\u003e\n \u003cp\u003e198 (77.95)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c4\"\u003e\n \u003cp\u003e5.215\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\n \u003cp\u003e0.022*\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eWheezes/rales\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c2\"\u003e\n \u003cp\u003e42 (30.43)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c3\"\u003e\n \u003cp\u003e72 (28.35)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c4\"\u003e\n \u003cp\u003e0.189\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\n \u003cp\u003e0.664\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eDecreased breath sound\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c2\"\u003e\n \u003cp\u003e10 (7.25)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c3\"\u003e\n \u003cp\u003e47 (18.50)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c4\"\u003e\n \u003cp\u003e9.119\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\n \u003cp\u003e0.003**\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eRadiological findings, n (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eAtelectasis\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c2\"\u003e\n \u003cp\u003e3 (2.17)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c3\"\u003e\n \u003cp\u003e8 (3.15)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c4\"\u003e\n \u003cp\u003e0.312\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\n \u003cp\u003e0.576\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003ePulmonary consolidation\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c2\"\u003e\n \u003cp\u003e5 (3.62)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c3\"\u003e\n \u003cp\u003e16 (6.30)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c4\"\u003e\n \u003cp\u003e1.263\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\n \u003cp\u003e0.261\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eComplications, n (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eGastrointestinal dysfunction\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c2\"\u003e\n \u003cp\u003e9 (6.52)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c3\"\u003e\n \u003cp\u003e29 (11.42)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c4\"\u003e\n \u003cp\u003e2.448\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\n \u003cp\u003e0.118\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eHypokalemia\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c2\"\u003e\n \u003cp\u003e10 (7.25)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c3\"\u003e\n \u003cp\u003e28 (11.02)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c4\"\u003e\n \u003cp\u003e1.457\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\n \u003cp\u003e0.227\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eHyponatremia\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c2\"\u003e\n \u003cp\u003e5 (3.62)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c3\"\u003e\n \u003cp\u003e7 (2.76)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c4\"\u003e\n \u003cp\u003e0.227\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\n \u003cp\u003e0.634\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eMyocardial damage\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c2\"\u003e\n \u003cp\u003e3 (2.17)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c3\"\u003e\n \u003cp\u003e5 (1.97)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c4\"\u003e\n \u003cp\u003e0.019\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\n \u003cp\u003e0.891\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003ctfoot\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"5\"\u003eNote: *\u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05, **\u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.01, ***\u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.001.\u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tfoot\u003e\n \u003c/table\u003e\n \u003c/div\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec13\" class=\"Section2\"\u003e\n \u003ch2\u003e2.2 Comparison of Immune Indicators\u003c/h2\u003e\n \u003cp\u003eThe abnormal rate of complement C3 in the bacterial co-infection group (9.85%) was higher than that in the viral co-infection group (4.60%), with a statistically significant difference (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.049). There were no significant differences in other immune indicators (C4, immunoglobulins, lymphocyte subsets) between the two groups (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026gt;\u0026thinsp;0.05). See Table \u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e2\u003c/span\u003e.\u003c/p\u003e\n \u003cdiv class=\"gridtable\"\u003e\u0026nbsp;\u003ctable float=\"Yes\" id=\"Tab3\" border=\"1\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003eComparison and Analysis of Immune Function\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003ccolgroup cols=\"5\"\u003e\u003c/colgroup\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eLab test\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colname=\"c2\"\u003e\n \u003cp\u003eMP-bacterial co-infection group (n\u0026thinsp;=\u0026thinsp;138)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colname=\"c3\"\u003e\n \u003cp\u003eMP-viral co-infection group (n\u0026thinsp;=\u0026thinsp;254)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colname=\"c4\"\u003e\n \u003cp\u003e\u003cem\u003e\u0026chi;2\u003c/em\u003e\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colname=\"c5\"\u003e\n \u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eC3 (\u0026gt;\u0026thinsp;1.8 g/L, \u0026lt;\u0026thinsp;0.9 g/L)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\n \u003cp\u003e13 (9.85)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\n \u003cp\u003e11 (4.60)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\n \u003cp\u003e3.868\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\n \u003cp\u003e0.049*\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eC4 (\u0026gt;\u0026thinsp;0.38 g/L, \u0026lt;\u0026thinsp;0.16 g/L)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\n \u003cp\u003e73 (55.30)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\n \u003cp\u003e118 (49.37)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\n \u003cp\u003e1.197\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\n \u003cp\u003e0.274\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eIgA (\u0026gt;\u0026thinsp;2.22 g/L, \u0026lt;\u0026thinsp;0.38 g/L)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\n \u003cp\u003e35 (26.52)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\n \u003cp\u003e49 (20.50)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\n \u003cp\u003e1.755\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\n \u003cp\u003e0.185\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eIgG (\u0026gt;\u0026thinsp;14.3 g/L, \u0026lt;\u0026thinsp;5.9 g/L)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\n \u003cp\u003e22 (16.67)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\n \u003cp\u003e41 (17.15)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\n \u003cp\u003e0.014\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\n \u003cp\u003e0.905\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eIgM (\u0026gt;\u0026thinsp;2.08 g/L, \u0026lt;\u0026thinsp;0.45 g/L)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\n \u003cp\u003e10 (7.58)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\n \u003cp\u003e33 (13.81)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\n \u003cp\u003e3.324\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\n \u003cp\u003e0.068\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eCD3+ (\u0026gt;\u0026thinsp;83%, \u0026lt;\u0026thinsp;55%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\n \u003cp\u003e15 (12.82)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\n \u003cp\u003e22 (10.43)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\n \u003cp\u003e0.431\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\n \u003cp\u003e0.511\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eCD3\u0026thinsp;+\u0026thinsp;CD4+ (\u0026gt;\u0026thinsp;57%, \u0026lt;\u0026thinsp;28%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\n \u003cp\u003e15 (12.82)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\n \u003cp\u003e30 (14.22)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\n \u003cp\u003e0.124\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\n \u003cp\u003e0.725\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eCD3\u0026thinsp;+\u0026thinsp;CD8+ (\u0026gt;\u0026thinsp;39%, \u0026lt;\u0026thinsp;10%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\n \u003cp\u003e3 (2.56)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\n \u003cp\u003e6 (2.84)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\n \u003cp\u003e0.022\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\n \u003cp\u003e0.882\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eCD4+/CD8+ (\u0026gt;\u0026thinsp;1.94%, \u0026lt;\u0026thinsp;0.98)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\n \u003cp\u003e52 (44.44)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\n \u003cp\u003e73 (34.60)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\n \u003cp\u003e3.094\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\n \u003cp\u003e0.079\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eCD3-CD19+ (\u0026gt;\u0026thinsp;19%, \u0026lt;\u0026thinsp;6%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\n \u003cp\u003e60 (51.28)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\n \u003cp\u003e102 (48.34)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\n \u003cp\u003e0.260\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\n \u003cp\u003e0.610\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eCD3-CD(16\u0026thinsp;+\u0026thinsp;56)+ (\u0026gt;\u0026thinsp;31%, \u0026lt;\u0026thinsp;7%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\n \u003cp\u003e37 (3.62)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\n \u003cp\u003e67 (31.75)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\n \u003cp\u003e0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\n \u003cp\u003e0.981\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eCD19\u0026thinsp;+\u0026thinsp;CD23+ (\u0026gt;\u0026thinsp;9.7%, \u0026lt;\u0026thinsp;3.8%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\n \u003cp\u003e52 (44.44)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\n \u003cp\u003e114 (54.03)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\n \u003cp\u003e2.766\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\n \u003cp\u003e0.096\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003ctfoot\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"5\"\u003eNote: Some data were missing for certain indicators. Percentages shown in the table were calculated based on the number of patients who completed the corresponding tests. *\u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05.\u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tfoot\u003e\n \u003c/table\u003e\n \u003c/div\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec14\" class=\"Section2\"\u003e\n \u003ch2\u003e2.3 Comparison of Coagulation Function\u003c/h2\u003e\n \u003cp\u003eThe elevated rate of D-D in the viral co-infection group was higher than that in the bacterial co-infection group (44.96% vs 33.06%, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.029), whereas the prolonged rate of APTT was lower than that in the bacterial co-infection group (72.80% vs 61.76%, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.036). Details are shown in Table \u003cspan refid=\"Tab4\" class=\"InternalRef\"\u003e3\u003c/span\u003e.\u003c/p\u003e\n \u003cdiv class=\"gridtable\"\u003e\u0026nbsp;\u003ctable float=\"Yes\" id=\"Tab4\" border=\"1\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003eComparison and Analysis of Coagulation Function\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003ccolgroup cols=\"5\"\u003e\u003c/colgroup\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eLab test\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colname=\"c2\"\u003e\n \u003cp\u003eMP-bacterial co-infection group (n\u0026thinsp;=\u0026thinsp;138)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colname=\"c3\"\u003e\n \u003cp\u003eMP-viral co-infection group (n\u0026thinsp;=\u0026thinsp;254)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colname=\"c4\"\u003e\n \u003cp\u003e\u0026chi;2\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colname=\"c5\"\u003e\n \u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003ePT (\u0026gt;\u0026thinsp;12.1 s)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c2\"\u003e\n \u003cp\u003e114(91.20)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\n \u003cp\u003e224(94.12)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\n \u003cp\u003e1.088\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\n \u003cp\u003e0.297\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eAPTT (\u0026gt;\u0026thinsp;36.5s)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c2\"\u003e\n \u003cp\u003e91(72.80)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\n \u003cp\u003e147(61.76)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\n \u003cp\u003e4.421\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\n \u003cp\u003e0.036*\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eFib (\u0026gt;\u0026thinsp;3.5g/L)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c2\"\u003e\n \u003cp\u003e106(84.80)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\n \u003cp\u003e207(86.97)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\n \u003cp\u003e0.326\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\n \u003cp\u003e0.568\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eTT (\u0026gt;\u0026thinsp;21s)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c2\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\n \u003cp\u003e1(0.42)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\n \u003cp\u003e0.527\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\n \u003cp\u003e0.468\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eAT-III (\u0026gt;\u0026thinsp;120%, \u0026lt;\u0026thinsp;80%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c2\"\u003e\n \u003cp\u003e28(22.40)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\n \u003cp\u003e74(31.09)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\n \u003cp\u003e3.715\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\n \u003cp\u003e0.054\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eD-D (\u0026gt;\u0026thinsp;550ug/L)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c2\"\u003e\n \u003cp\u003e41(33.06)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\n \u003cp\u003e107(44.96)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\n \u003cp\u003e4.771\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\n \u003cp\u003e0.029*\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eFDP (\u0026gt;\u0026thinsp;5000ug/L)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c2\"\u003e\n \u003cp\u003e5(9.26)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\n \u003cp\u003e13(7.10)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\n \u003cp\u003e0.276\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\n \u003cp\u003e0.599\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n \u003c/div\u003e\n \u003cp\u003eNote: Prothrombin Time (PT); Activated Partial Thromboplastin Time (APTT); Fibrinogen (Fib); Thrombin Time (TT); Antithrombin III (AT-III); D-dimer (D-D); Fibrin Degradation Products (FDP). Some data were missing for certain indicators. Percentages shown in the table were calculated based on the number of patients who completed the corresponding tests. *\u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05.\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec15\" class=\"Section2\"\u003e\n \u003ch2\u003e2.4 Comparison of Inflammatory Indicators\u003c/h2\u003e\n \u003cp\u003eThe elevated rate of procalcitonin (PCT) in the bacterial co-infection group (20.99%) was significantly higher than that in the viral co-infection group (5.68%, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.001). In contrast, the elevated rate of serum amyloid A (SAA) in the viral co-infection group (94.29%) was significantly higher than that in the bacterial co-infection group (68.57%, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.006). No significant differences were observed in the abnormal rates of heparin-binding protein (HBP) and C-reactive protein (CRP) between the two groups (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026gt;\u0026thinsp;0.05). See Table \u003cspan refid=\"Tab5\" class=\"InternalRef\"\u003e4\u003c/span\u003e.\u003c/p\u003e\n \u003cdiv class=\"gridtable\"\u003e\u0026nbsp;\u003ctable float=\"Yes\" id=\"Tab5\" border=\"1\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 4\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003eComparison and Analysis of Inflammatory Indicators\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003ccolgroup cols=\"5\"\u003e\u003c/colgroup\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eLab test\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colname=\"c2\"\u003e\n \u003cp\u003eMP-bacterial co-infection group (n\u0026thinsp;=\u0026thinsp;138)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colname=\"c3\"\u003e\n \u003cp\u003eMP-viral co-infection group (n\u0026thinsp;=\u0026thinsp;254)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colname=\"c4\"\u003e\n \u003cp\u003e\u0026chi;2\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colname=\"c5\"\u003e\n \u003cp\u003eP\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003ePCT (\u0026gt;\u0026thinsp;0.5 ng/mL)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\n \u003cp\u003e17 (20.99)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\n \u003cp\u003e10 (5.68)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\n \u003cp\u003e13.821\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\n \u003cp\u003e\u0026lt;\u0026thinsp;0.001***\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eSAA (\u0026gt;\u0026thinsp;10 mg/L)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\n \u003cp\u003e24 (68.57)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\n \u003cp\u003e33 (94.29)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\n \u003cp\u003e7.652\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\n \u003cp\u003e0.006**\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eHBP (\u0026gt;\u0026thinsp;11.4 ng/mL)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\n \u003cp\u003e52 (86.67)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\n \u003cp\u003e56 (84.85)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\n \u003cp\u003e0.085\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\n \u003cp\u003e0.771\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003esCRP (\u0026gt;\u0026thinsp;8 mg/L)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\n \u003cp\u003e83 (61.03)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\n \u003cp\u003e135 (54.22)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\n \u003cp\u003e1.662\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\n \u003cp\u003e0.197\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003ctfoot\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"5\"\u003eNote: Some data were missing for certain indicators. Percentages shown in the table were calculated based on the number of patients who completed the corresponding tests. **P\u0026thinsp;\u0026lt;\u0026thinsp;0.01, ***\u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.001.\u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tfoot\u003e\n \u003c/table\u003e\n \u003c/div\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec16\" class=\"Section2\"\u003e\n \u003ch2\u003e2.5 Analysis of Viral Spectrum\u003c/h2\u003e\n \u003cp\u003eA total of 300 virus strains were detected in children with viral co-infection. (HRV showed the highest constituent ratio (53.67%, 161/300) and was the predominant virus in spring and summer, followed by HCOV (11.67%) and RSV (11.00%). Details are presented in Table \u003cspan refid=\"Tab6\" class=\"InternalRef\"\u003e5\u003c/span\u003e.\u003c/p\u003e\n \u003cdiv class=\"gridtable\"\u003e\u0026nbsp;\u003ctable float=\"Yes\" id=\"Tab6\" border=\"1\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 5\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003eAnalysis of Detected Viruses in Different Seasons\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003ccolgroup cols=\"6\"\u003e\u003c/colgroup\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eVirus\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colname=\"c2\"\u003e\n \u003cp\u003eSpring (n)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colname=\"c3\"\u003e\n \u003cp\u003eSummer (n)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colname=\"c4\"\u003e\n \u003cp\u003eAutumn (n)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colname=\"c5\"\u003e\n \u003cp\u003eWinter (n)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colname=\"c6\"\u003e\n \u003cp\u003eTotal (n)\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eHRV\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\n \u003cp\u003e41\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\n \u003cp\u003e61\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\n \u003cp\u003e36\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\n \u003cp\u003e23\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\n \u003cp\u003e161\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eHCOV\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\n \u003cp\u003e7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\n \u003cp\u003e18\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\n \u003cp\u003e10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\n \u003cp\u003e35\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eHRSV\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\n \u003cp\u003e8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\n \u003cp\u003e10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\n \u003cp\u003e12\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\n \u003cp\u003e33\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eHPIV\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\n \u003cp\u003e12\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\n \u003cp\u003e10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\n \u003cp\u003e29\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eHMPV\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\n \u003cp\u003e13\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eBoca\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\n \u003cp\u003e6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\n \u003cp\u003e12\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eInfA H3N2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\n \u003cp\u003e6\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eADV\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eCh\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eInfA H1N1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eInfb\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eTotal\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\n \u003cp\u003e74\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\n \u003cp\u003e114\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\n \u003cp\u003e81\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\n \u003cp\u003e31\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\n \u003cp\u003e300\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n \u003c/div\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec17\" class=\"Section2\"\u003e\n \u003ch2\u003e2.6 Analysis of Viral Co-infection Patterns\u003c/h2\u003e\n \u003cp\u003eAnalysis of viral co-infection patterns: MP co-infection with a single virus was the main pattern (85.00%, 254/299), dual viral co-infection accounted for 11.00%, and triple viral co-infection accounted for 4.00%. Common viral combinations included HRV/HPIV and HRV/RSV, as shown in Fig. \u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e.\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec18\" class=\"Section2\"\u003e\n \u003ch2\u003e2.7 Annual Composition of Bacterial Spectrum\u003c/h2\u003e\n \u003cp\u003eA total of 139 bacterial strains were isolated from 138 children with bacterial co-infection, among which Gram-positive bacteria accounted for 75.54%. \u003cem\u003eStreptococcus pneumoniae\u003c/em\u003e was the absolute dominant pathogen, accounting for 58.99% (82/139), followed by \u003cem\u003eHaemophilus influenzae\u003c/em\u003e (24/139, 17.27%) and \u003cem\u003eStaphylococcus aureus\u003c/em\u003e (23/139, 16.55%). See Table \u003cspan refid=\"Tab7\" class=\"InternalRef\"\u003e6\u003c/span\u003e.\u003c/p\u003e\n \u003cdiv class=\"gridtable\"\u003e\u0026nbsp;\u003ctable float=\"Yes\" id=\"Tab7\" border=\"1\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 6\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003eAnnual Distribution of Bacterial Strains.\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003ccolgroup cols=\"6\"\u003e\u003c/colgroup\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eCo-infecting Bacteria\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colname=\"c2\"\u003e\n \u003cp\u003eNo. of Strains (n)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colname=\"c3\"\u003e\n \u003cp\u003e2021\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colname=\"c4\"\u003e\n \u003cp\u003e2022\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colname=\"c5\"\u003e\n \u003cp\u003e2023\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colname=\"c6\"\u003e\n \u003cp\u003ePercentage (%)\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003e\u003cem\u003eStreptococcus pneumoniae\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\n \u003cp\u003e82\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c3\"\u003e\n \u003cp\u003e34\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\n \u003cp\u003e25\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\n \u003cp\u003e23\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c6\"\u003e\n \u003cp\u003e58.99\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003e\u003cem\u003eHaemophilus influenzae\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\n \u003cp\u003e24\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c3\"\u003e\n \u003cp\u003e8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\n \u003cp\u003e7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\n \u003cp\u003e9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c6\"\u003e\n \u003cp\u003e17.27\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003e\u003cem\u003eStaphylococcus aureus\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\n \u003cp\u003e23\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c3\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\n \u003cp\u003e12\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\n \u003cp\u003e8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c6\"\u003e\n \u003cp\u003e16.55\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003e\u003cem\u003eMoraxella catarrhalis\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c3\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c6\"\u003e\n \u003cp\u003e3.60\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003e\u003cem\u003eKlebsiella pneumoniae\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c3\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c6\"\u003e\n \u003cp\u003e1.44\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003e\u003cem\u003eAcinetobacter baumanni\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c3\"\u003e\n \u003cp\u003e.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c6\"\u003e\n \u003cp\u003e0.72\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003e\u003cem\u003eStenotrophomonas maltophilia\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c3\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c6\"\u003e\n \u003cp\u003e0.72\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003e\u003cem\u003ePseudomonas aeruginosa\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c3\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c6\"\u003e\n \u003cp\u003e0.72\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eTotal\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\n \u003cp\u003e139\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c3\"\u003e\n \u003cp\u003e46\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\n \u003cp\u003e49\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\n \u003cp\u003e44\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c6\"\u003e\n \u003cp\u003e100\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n \u003c/div\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec19\" class=\"Section2\"\u003e\n \u003ch2\u003e2.8 Drug Susceptibility Results of \u003cem\u003eStreptococcus pneumoniae\u003c/em\u003e\u003c/h2\u003e\n \u003cp\u003e\u003cem\u003eStreptococcus pneumoniae\u003c/em\u003e was the major pathogen, with 82 strains isolated in total. Among them, 68 strains were dominant strains in pure culture from qualified sputum samples and were included in the final analysis of drug susceptibility results; the remaining 14 strains failed to complete full-set drug susceptibility testing due to culture conditions or specimen quality issues. As shown in Table \u003cspan refid=\"Tab8\" class=\"InternalRef\"\u003e7\u003c/span\u003e, the drug resistance rate to erythromycin (macrolide antibiotic) was as high as 100.00%. The resistance rate of \u003cem\u003eStreptococcus pneumoniae\u003c/em\u003e to tetracycline was above 80% from 2021 to 2022 and decreased in 2023. However, the susceptibility rates to penicillin G, cefotaxime and chloramphenicol remained at 84.75%, 90.32% and 92.65%, respectively, and 100.00% susceptibility was observed to rifampicin, linezolid, levofloxacin, vancomycin and other agents.\u003c/p\u003e\n \u003cdiv class=\"gridtable\"\u003e\u0026nbsp;\u003ctable float=\"Yes\" id=\"Tab8\" border=\"1\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 7\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003eAnalysis of Drug Susceptibility Results of \u003cem\u003eStreptococcus pneumoniae\u003c/em\u003e\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003ccolgroup cols=\"7\"\u003e\u003c/colgroup\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e\n \u003cp\u003eAntimicrobial Agents\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e\n \u003cp\u003e2021 (n\u0026thinsp;=\u0026thinsp;34)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colspan=\"2\" nameend=\"c5\" namest=\"c4\"\u003e\n \u003cp\u003e2022 (n\u0026thinsp;=\u0026thinsp;13)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colspan=\"2\" nameend=\"c7\" namest=\"c6\"\u003e\n \u003cp\u003e2023 (n\u0026thinsp;=\u0026thinsp;21)\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003cth align=\"left\" colname=\"c2\"\u003e\n \u003cp\u003eNo. of Resistant Strains (n)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colname=\"c3\"\u003e\n \u003cp\u003eResistance Rate (%)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colname=\"c4\"\u003e\n \u003cp\u003eNo. of Resistant Strains (n)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colname=\"c5\"\u003e\n \u003cp\u003eResistance Rate (%)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colname=\"c6\"\u003e\n \u003cp\u003eNo. of Resistant Strains (n)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colname=\"c7\"\u003e\n \u003cp\u003eResistance Rate (%)\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eErythromycin\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\n \u003cp\u003e34\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c3\"\u003e\n \u003cp\u003e100\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\n \u003cp\u003e13\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c5\"\u003e\n \u003cp\u003e100\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c6\"\u003e\n \u003cp\u003e21\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c7\"\u003e\n \u003cp\u003e100\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eClindamycin\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\n \u003cp\u003e34\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c3\"\u003e\n \u003cp\u003e100\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\n \u003cp\u003e13\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c5\"\u003e\n \u003cp\u003e100\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c6\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c7\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eTetracycline\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\n \u003cp\u003e29\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c3\"\u003e\n \u003cp\u003e85.29\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\n \u003cp\u003e11\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c5\"\u003e\n \u003cp\u003e84.62\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c6\"\u003e\n \u003cp\u003e19\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c7\"\u003e\n \u003cp\u003e90.48\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eSulfamethoxazole-trimethoprim\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\n \u003cp\u003e27\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c3\"\u003e\n \u003cp\u003e79.41\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\n \u003cp\u003e11\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c5\"\u003e\n \u003cp\u003e84.62\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c6\"\u003e\n \u003cp\u003e13\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c7\"\u003e\n \u003cp\u003e61.90\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eQuinupristin/dalfopristin\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\n \u003cp\u003e21\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c3\"\u003e\n \u003cp\u003e61.76\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\n \u003cp\u003e11\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c5\"\u003e\n \u003cp\u003e84.62\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c6\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c7\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003ePenicillin G\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c3\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c5\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c6\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c7\"\u003e\n \u003cp\u003e4.76\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eCefotaxime\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c3\"\u003e\n \u003cp\u003e11.76\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c5\"\u003e\n \u003cp\u003e38.46\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c6\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c7\"\u003e\n \u003cp\u003e14.29\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eChloramphenicol\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c3\"\u003e\n \u003cp\u003e8.82\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c5\"\u003e\n \u003cp\u003e7.69\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c6\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c7\"\u003e\n \u003cp\u003e4.76\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eRifampicin\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c3\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c5\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c6\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c7\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eLinezolid\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c3\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c5\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c6\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c7\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eLevofloxacin\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c3\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c5\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c6\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c7\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eVancomycin\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c3\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c5\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c6\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c7\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eAmoxicillin\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c3\"\u003e\n \u003cp\u003e11.76\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c6\"\u003e\n \u003cp\u003e6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c7\"\u003e\n \u003cp\u003e28.57\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colname=\"c1\"\u003e\n \u003cp\u003eMoxifloxacin\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c3\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c5\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c6\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colname=\"c7\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003ctfoot\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"7\"\u003eNote: \u0026ldquo;-\u0026rdquo; indicates that the corresponding antibiotic was not tested.\u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tfoot\u003e\n \u003c/table\u003e\n \u003c/div\u003e\n\u003c/div\u003e"},{"header":"4 Discussion","content":"\u003cp\u003eMPP is the leading cause of community-acquired pneumonia (CAP) in children aged 3\u0026ndash;15 years\u003csup\u003e[\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]\u003c/sup\u003e. Co-infection with viruses or bacteria has become a key factor exacerbating disease severity and complicating clinical management. Compared with single MPP infection, co-infection is associated with more severe clinical symptoms and a higher incidence of complications\u003csup\u003e[\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]\u003c/sup\u003e. Given the regional and seasonal variations in the pathogen spectrum of MPP co-infections, larger-sample epidemiological and mechanistic studies are urgently needed to guide clinical practice. This study compared the clinical characteristics, immune, coagulation, and inflammatory indicators between children with MP plus viral co-infection and those with MP plus bacterial co-infection, providing a basis for clinical differentiation and treatment.\u003c/p\u003e \u003cp\u003eChildren in the MP plus viral co-infection group were older, consistent with the immune developmental characteristics that older children have a wider range of activities and higher risk of viral exposure, whereas younger children have immature immune systems and are more susceptible to secondary bacterial infections\u003csup\u003e[\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e]\u003c/sup\u003e. The significant difference in onset seasons provides preliminary clues for clinical suspected diagnosis across seasons (viral infections peaked in spring, while bacterial infections predominated in summer and autumn). This may be related to increased viral activity and variable climate in spring, which reduce respiratory mucosal resistance, as well as suitable temperatures for bacterial proliferation in summer and autumn. These findings are consistent with those reported by Ge et al. in 2025, who noted a peak of MP plus viral coinfection in spring\u003csup\u003e[\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e]\u003c/sup\u003e. Regarding symptoms and pulmonary signs, the incidence of vomiting was higher in the MP plus bacterial co-infection group, while moist rales and decreased breath sounds were more common in the MP plus viral co-infection group. Viral infections may more readily induce increased airway secretions and impaired pulmonary ventilation, consistent with the pathological mechanism of viral invasion into respiratory epithelial cells, causing mucosal inflammation and edema\u003csup\u003e[\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e]\u003c/sup\u003e. In clinical practice, age, onset season, and core symptoms can be used to preliminarily determine the infection type, providing a reference for early intervention.\u003c/p\u003e \u003cp\u003eBased on identified differences in clinical characteristics, we further analyzed the immune status of the two groups. The results showed a higher abnormal rate of complement C3 in the MP plus bacterial co-infection group, suggesting that early bacterial infection may activate the complement system via the classical or alternative pathway, participating in pathogen clearance and inflammatory responses. Abnormal elevation or reduction of C3 may reflect stronger immune activation induced by bacterial infection\u003csup\u003e[\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e]\u003c/sup\u003e. However, there were no significant differences in immunoglobulins or T lymphocyte subsets between the two groups. This may be because MP infection itself has already exerted certain effects on the children\u0026rsquo;s immune function, masking the specific immune differences between bacterial and viral coinfections. It also indicates that changes in immune function during MP coinfection may be more closely related to MP itself rather than the type of secondary pathogen.\u003c/p\u003e \u003cp\u003eCoagulation dysfunction is a common manifestation of MPP, and its mechanism is associated with MP-induced cytokine release, vascular injury, and increased thrombotic risk\u003csup\u003e[\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e]\u003c/sup\u003e. In this study, the rate of prolonged APTT was higher in the bacterial co-infection group, which may be related to direct endothelial cell damage and activation of the intrinsic coagulation pathway by bacteria. In contrast, D-D elevation was more significant in the viral co-infection group, suggesting that viral infection is more likely to trigger systemic inflammatory responses and fibrinolytic system activation, increasing the risk of thrombosis. Previous studies have identified D-D as an independent risk factor for thrombosis\u003csup\u003e[\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e]\u003c/sup\u003e. Close monitoring and intervention of coagulation function are clinically necessary for such children to prevent thrombotic complications.\u003c/p\u003e \u003cp\u003eAmong inflammatory indicators, PCT and SAA showed core differential diagnostic value. PCT was significantly elevated in bacterial infections but not obviously increased in viral infections, consistent with previous studies reporting the high specificity of PCT for bacterial infection\u003csup\u003e[\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e]\u003c/sup\u003e. The sensitivity of SAA in viral infections reached 94.29%, significantly higher than that in the bacterial infection group, in line with the characteristic rapid early elevation of SAA in viral infections\u003csup\u003e[\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e]\u003c/sup\u003e. No significant differences were observed in serum levels of HBP and CRP between the two groups (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026gt;\u0026thinsp;0.05). PCT showed high specificity for identifying concurrent bacterial infection, while SAA exhibited high sensitivity for indicating concurrent viral infection. Combined detection of the two markers is complementary, providing key references for early differentiation and initial treatment decisions before pathogen results are available.\u003c/p\u003e \u003cp\u003eRegarding the viral spectrum, single viral co-infection with MP was the most common pattern, and co-infection with two or more viruses was also not uncommon, suggesting that multiplex pathogen detection should be emphasized in children with MP infection. HRV was the predominant virus in the Suzhou area, consistent with previous findings\u003csup\u003e[\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e]\u003c/sup\u003e. However, marked regional differences exist in the predominant viral spectrum compared with Beijing, Liaoning in China, and Russia abroad\u003csup\u003e[\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e]\u003c/sup\u003e. These differences may stem from climatic conditions in East China, immune backgrounds of the pediatric population, and local epidemic strains of pathogens, highlighting that respiratory pathogen surveillance must be localized and clinical experience cannot be simply applied across regions.\u003c/p\u003e \u003cp\u003eAmong bacterial isolates, the top three pathogens were \u003cem\u003eStreptococcus pneumoniae\u003c/em\u003e, \u003cem\u003eHaemophilus influenzae\u003c/em\u003e, and \u003cem\u003eStaphylococcus aureus\u003c/em\u003e, consistent with the distribution of common pathogens causing community-acquired pneumonia\u003csup\u003e[\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e]\u003c/sup\u003e. Drug susceptibility analysis of 68 \u003cem\u003eStreptococcus pneumoniae\u003c/em\u003e strains (34 in 2021, 13 in 2022, 21 in 2023) revealed: Resistance rate to erythromycin remained 100% from 2021 to 2023; Resistance rate to clindamycin was 100% in 2021\u0026ndash;2022 (not tested in 2023); Tetracycline resistance increased from 85.29% (2021) to 90.48% (2023); Resistance rate to compound sulfamethoxazole decreased from 79.41% (2021) and 84.62% (2022) to 29.42% (2023); Among β-lactams, penicillin G remained 100% sensitive over the three years; Cefotaxime resistance rose from 11.76% (2021) to 38.46% (2022) and fell to 14.29% (2023); Amoxicillin resistance increased from 11.76% (2021) to 28.57% (2023); Levofloxacin, moxifloxacin, vancomycin, and linezolid showed 100% susceptibility.\u003c/p\u003e \u003cp\u003eThese findings provide important references for empirical antimicrobial therapy. For children highly suspected of MP plus bacterial co-infection, especially co-infection with Streptococcus pneumoniae, monotherapy with highly resistant agents such as macrolides should be avoided. β-lactam antibiotics may be preferred, and third-generation cephalosporins or other sensitive agents can be used if the response is poor, so as to prevent antibiotic abuse.\u003c/p\u003e \u003cp\u003eIn conclusion, differences exist between children with MP plus bacterial coinfection and those with viral co-infection in age, onset season, clinical symptoms, immune function, coagulation function, and inflammatory indicators. Combined detection of PCT, SAA, D-D and other markers facilitates early differentiation of infection types. This study is a retrospective single-center analysis including only hospitalized children, without coverage of outpatients with mild disease, which may lead to selection bias. Long-term follow-up of prognosis and treatment efficacy was not performed. Future multicenter and prospective studies incorporating comprehensive pathogen detection techniques such as metagenomic next-generation sequencing are warranted to further clarify the dynamic changes of co-infection, pathogen interactions, and their impacts on prognosis, so as to provide higher-level evidence for the development of individualized treatment and prevention strategies.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eEthics and consent to participate\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe project is a retrospective study of data and only includes specific data. It was reviewed and approved by the Medical Ethics Committee of the Children\u0026apos;s Hospital of Soochow University (Ethics batch number: 2025CS239).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for publication\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable. This manuscript does not contain any individual person\u0026rsquo;s data in any form (including individual details, images or videos).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAvailability of Data and Materials\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe datasets used and/or analysed during the current study available from the corresponding author on reasonable request.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConflicts of interest\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAll other authors report no potential conflicts of interest.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding support\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eSuzhou Municipal Health Commission (KJXW2023025), Guided Project of Jiangsu Provincial Natural Science Foundation (Z2025037).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthor contributions\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eYX Z and Y J conceived the study and designed the experiments. X Z provide financial support and collected the data. YX Z and Y J analysed the data and interpreted the results. YX Z and Y J drafted the manuscript, and all authors critically revised the manuscript for intellectual content, and read and approved the final manuscript.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAcknowledgments\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eWe thank the staff from the\u0026nbsp;\u003cem\u003eDepartment of Clinical Laboratory, Children\u0026apos;s Hospital of Soochow University\u003c/em\u003e, who took part in the study.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eDiaz MH, Hersh AL, Olson J, et al. Mycoplasma pneumoniae Infections in Hospitalized Children-United States, 2018\u0026ndash;2024[J]. MMWR Morb Mortal Wkly Rep. 2025;74(23):394\u0026ndash;400.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eChen F, Zhang FR. Early Clinical Characteristics and Related Risk Factors of Refractory Mycoplasma Pneumoniae Pneumonia in Children[J]. China Trop Med. 2024;24(07):777\u0026ndash;82.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eDing LL, Jiang YH. Biomarkers associated with the diagnosis and prognosis of Mycoplasma pneumoniae pneumonia in children: a review[J]. Front Cell Infect Microbiol. 2025;15:1552144: 1\u0026ndash;18.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eYao C, Zhang X, Xu R. Distribution characteristics of the bronchoalveolar lavage fluid microbiota in children with refractory mycoplasma pneumonia at different stages and its relationship with immune function[J]. Chin J Contemp Pediatr. 2025;27(08):945\u0026ndash;50.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eYu Y, Ji R, Xia Y et al. Multicenter Analysis of Clinical Characteristics and Risk Factors for Liver Injury in Severe Mycoplasma Pneumoniae Pneumonia[J]. 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Int J Clin Exp Med. 2015;8(9):15666\u0026ndash;74.\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"italian-journal-of-pediatrics","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"itjp","sideBox":"Learn more about [Italian Journal of Pediatrics](http://ijponline.biomedcentral.com)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/ITJP/default.aspx","title":"Italian Journal of Pediatrics","twitterHandle":"@BioMedCentral","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"BMC/SO AJ","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"Children, Mycoplasma pneumoniae, Mixed infection, Epidemiological characteristics, Pathogen spectrum, Laboratory indicators","lastPublishedDoi":"10.21203/rs.3.rs-9446289/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-9446289/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003eObjective\u003c/h2\u003e \u003cp\u003eTo analyze the epidemiological, clinical and laboratory differences between \u003cem\u003eMycoplasma pneumoniae\u003c/em\u003e (MP) mixed with viral or bacterial infections in children in Suzhou, and provide evidence for early clinical differentiation and localized prevention.\u003c/p\u003e\u003ch2\u003eMethods\u003c/h2\u003e \u003cp\u003eA retrospective study included 392 children with MP infection, divided into MP mixed viral infection group (n\u0026thinsp;=\u0026thinsp;254) and bacterial infection group (n\u0026thinsp;=\u0026thinsp;138). Epidemiological characteristics, clinical manifestations, immune, coagulation, inflammatory indicators, pathogen distribution and bacterial drug susceptibility were compared.\u003c/p\u003e\u003ch2\u003eResults\u003c/h2\u003e \u003cp\u003eThe viral group had older children [6 (3, 8) vs 4 (2, 6.25) years, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.001], higher incidence in spring (51.97% vs 18.12%, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.001), and more wet rales and decreased breath sounds (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05). The bacterial group was more common in summer and autumn, with higher vomiting incidence (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.022), higher C3 abnormal rate (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.049) and more significant procalcitonin elevation (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.001). The viral group had higher serum amyloid A and D-dimer (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05). Human rhinovirus was the predominant virus (53.67%), and \u003cem\u003eStreptococcus pneumoniae\u003c/em\u003e was the main bacterium (58.99%) with 100% erythromycin resistance but high sensitivity to penicillin G and cefotaxime.\u003c/p\u003e\u003ch2\u003eConclusions\u003c/h2\u003e \u003cp\u003eDifferences exist in age, season, clinical and laboratory indicators between the two groups. Combined detection of procalcitonin, serum amyloid A and D-dimer aids early differentiation. Local pathogen spectrum and severe bacterial drug resistance require localized surveillance and rational antibiotic use.\u003c/p\u003e","manuscriptTitle":"Comparative analysis of clinical characteristics and laboratory indicators of children with mixed bacterial and viral infections of Mycoplasma pneumoniae","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-05-11 08:16:58","doi":"10.21203/rs.3.rs-9446289/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Major revision","date":"2026-05-13T02:50:11+00:00","index":"","fulltext":""},{"type":"reviewerAgreed","content":"","date":"2026-04-29T15:35:42+00:00","index":0,"fulltext":""},{"type":"reviewersInvited","content":"","date":"2026-04-29T13:42:51+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2026-04-18T08:07:12+00:00","index":"","fulltext":""},{"type":"submitted","content":"Italian Journal of Pediatrics","date":"2026-04-17T04:25:48+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"italian-journal-of-pediatrics","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"itjp","sideBox":"Learn more about [Italian Journal of Pediatrics](http://ijponline.biomedcentral.com)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/ITJP/default.aspx","title":"Italian Journal of Pediatrics","twitterHandle":"@BioMedCentral","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"BMC/SO AJ","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"d4aaf49d-5c90-47d4-9d5a-034a8c6fb290","owner":[],"postedDate":"May 11th, 2026","published":true,"recentEditorialEvents":[{"type":"decision","content":"Major revision","date":"2026-05-13T02:50:11+00:00","index":"","fulltext":""},{"type":"reviewerAgreed","content":"","date":"2026-04-29T15:35:42+00:00","index":0,"fulltext":""},{"type":"reviewersInvited","content":"","date":"2026-04-29T13:42:51+00:00","index":"","fulltext":""}],"rejectedJournal":[],"revision":"","amendment":"","status":"in-revision","subjectAreas":[],"tags":[],"updatedAt":"2026-05-13T06:57:29+00:00","versionOfRecord":[],"versionCreatedAt":"2026-05-11 08:16:58","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-9446289","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-9446289","identity":"rs-9446289","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}