Comparison of laboratory test results and treatments between macrolide-resistant and macrolide-sensitive Mycoplasma pneumoniae pneumonia in children

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The development and widespread of macrolide-resistant M. pneumoniae (MRMP) has increased the difficulty of treating MPP. This study aimed to investigate the differences in laboratory test results and treatment results between MPP caused by MRMP and macrolide-sensitive M. pneumoniae (MSMP) in children. The patients were recruited from among the hospitalized children at the Children’s Hospital Affiliated to Zhengzhou University. Pneumonia was diagnosed via chest CT. The laboratory test results investigated included white blood cell (WBC) count, neutrophil count (NEUT), lymphocyte count (LYM), C-reactive protein (CRP), lactate dehydrogenase (LDH), and D-dimer; treatment results, including antibiotics used, hospitalization days and bronchoscopyuse, were also obtained. MRMP-infected MPP patients demonstrated a greater rate of lung consolidation; a greater frequency of bronchoscope use and second-line antibiotic use; higher levels of CRP, LDH and D-dimer; and more hospitalization days than MPP patients caused by MSMP. There were no differences with regard to the WBC, NEUT, or LYM counts between MRMP patients and MSMP patients. Conclusions: The worsening of MPP caused by MRMP could be more severe than that caused by MSMP because of poor laboratory and chest CT results, and MRMP infection increases the difficulty of treatment. Macrolide resistance. Mycoplasma pneumoniae. Children. Laboratory test. Treatment What is Known Macrolide-resistant Mycoplasma pneumoniae strains have emerged and developed rapidly in recent years, placing greater burdens on the treatment of these infections in children. The lack of knowledge about laboratory tests and treatments requires additional clinical investigation. What is New: We retrospectively analyzed and compared the laboratory and imaging results and treatments for macrolide-resistant and macrolide-sensitive mycoplasma pneumoniae pneumonia in a Chinese pediatric cohort. Our work may improve the understanding of macrolide-resistant Mycoplasma pneumoniae-related laboratory test results and treatments for pneumonia patients. Introduction Mycoplasma pneumoniae ( M. pneumoniae ) is one of the main causes of community-acquired pneumonia (CAP) and is responsible for 10-40% of CAPs[1]. M. pneumoniae pneumonia (MPP) can affect people of any age but is most common in children. Since it was first isolated and reported in Japan[2], macrolide-resistant M. pneumoniae (MRMP) infection has developed rapidly worldwide. The increase in the MPP caused by MRMP has increased the difficulty in treating due to the reduced effects of macrolides, and an increasing number of refractory MPPs (RMPPs) are being identified in pediatric patients. MRMP has been caused by the wide and inappropriate use of macrolides in recent years, and macrolide resistance has reached 80-90% in China according to previous studies[3-5]. Previous studies revealed that single-point nucleotide mutations occurring in the V region of the 23S rRNA of the M. pneumoniae genome correlate with macrolide resistance[6]. The macrolide resistance-related mutations mainly occur at sites 2063, 2064, 2617 and 2067, among which 2063 and 2064 were the predominant macrolide resistance sites[7-9]. Mutations at sites 2063 and 2064 usually cause high levels of macrolide resistance, whereas mutations at sites 2617 and 2067 result in low levels of macrolide resistance[10]. M. pneumoniae is naturally resistant to β-lactam antibiotics because of cell wall deficiency. Tetracycline can cause tooth staining and enamel hypoplasia and can cause gastrointestinal irritation, liver toxicity and other side effects; therefore, its use is prohibited in children aged less than 8 years. Quinolones are prohibited for use in children because they can cause cartilage and joint damage and affect bone development. Macrolides are regarded as first-line treatments for M. pneumoniae infections in children due to their low side effects and high intracellular concentrations. Because the effects of macrolides on the treatment of MPP caused by MRMP are limited, doxycycline and levofloxacin are considered alternative treatments and have achieved effective outcomes[11-13]. The use of corticosteroids in MPP treatment could prohibit the inflammatory process by modulating immunity[14]. The intensity of inflammation is usually reflected by laboratory test parameters such as the white blood cell (WBC) count, C-reactive protein (CRP) level and lactate dehydrogenase (LDH) level. D-dimer is the most important indicator of thrombogenesis and thrombolytic activity, and D-dimer can be elevated in pulmonary infections[15]. In this study, we investigated laboratory test results, including WBC, CRP, LDH, D-dimer, neutrophil count (NEUT) and lymphocyte count (LYM), in MRMP-infected and macrolide-sensitive M. pneumoniae (MSMP) MPP patients. Treatment parameters, including antibiotic use, hospitalization duration and bronchoscopic use, were also studied for these two kinds of patients. This study will provide better knowledge of MPP caused by MRMP and MSMP and aid in future diagnosis and treatment. Methods Study subjects The study subjects were recruited randomly from among the children hospitalized for MPP at the Children’s Hospital Affiliated to Zhengzhou University from December 2023 to January 2024. Patients with coinfections of other pathogens, such as influenza virus, syncytial virus, adenovirus and bacteria other than M. pneumoniae, were excluded from the study. Patients with basic diseases of other body systems except the respiratory system were also not considered. Population characteristics, including age and sex, were recorded, and written informed consent was obtained from all the patients or their guardians. Diagnosis, imaging examination, laboratory tests and treatments M. pneumoniae infection and macrolide resistance were tested via real-time PCR (RT–PCR). Throat swab specimens were collected from the children and kept in specialized tubes with fluids for DNA and RNA extraction. RNA was extracted and then tested for M. pneumoniae infection with commercial kits according to the manufacturer’s instructions. RT‒PCR tests targeting the A2063G and A2064G mutations in region V of the 23S rRNA gene of M. pneumoniae were applied to test macrolide resistance. Pneumonia was diagnosed by chest CT, and the presence of lung consolidation was considered. Routine blood tests were performed for all the patients, and whole peripheral blood was collected for analysis via an automatic blood cell analyzer, which could detect CRP levels at the same time. CRP, WBC, NEUT and LYM were recorded from the routine blood test results. For the biochemical analysis of LDH and D-dimer levels, peripheral blood was collected into pro-coagulation and sodium citrate anticoagulant tubes, respectively, and the serum and plasma were separated via centrifugation. The MPP patients were treated with antibiotics (azithromycin, doxycycline and levofloxacin), bronchoscopy and other regular treatments. Second-line antibiotic treatment was considered if the symptoms did not improve with the use of macrolides or if the patient had severe MPP directly confirmed by MRMP. We focused on patient treatments, including hospitalization days, frequency of bronchoscope use and second-line antibiotic use. Statistical analysis The statistical analysis in the study was completed with the use of IBM SPSS Statistics 21. Quantitative data are expressed as the mean ± standard deviation (SD) to demonstrate the average value and variation, and Student’s t test was used for comparisons between two groups. For qualitative data, the chi-square test was performed for comparisons between two groups. P<0.05 was considered to indicate statistical significance. Results Population characteristics In the present study, 50 MRMP-infected MPP patients and 55 MSMP-infected patients were included. The number of male and female children in each group and the ages of the study subjects are shown in Table 1. There was no significant difference with regard to age or sex between MRMP- and MSMP-infected patients. Table 1 Sex and ages of the study subjects Group MRMP MSMP Sex (male/female) 28/22 27/28 Age (years, mean± SD) 6.81±2.06 6.34 ±1.94 Laboratory test results The laboratory test results, including WBC, NEUT, LYM, LDH, D-dimer and CRP levels, are shown in Table 2. The LDH, D-dimer and CRP levels were significantly greater in the MRMP-infected MPP patients than in the MSMP patients (P0.05). Table 2 Laboratory test results for MRMP- and MSMP-infected patients (mean± SD) Group MRMP MSMP WBC (10 9 /L) 8.35±2.36 8.96±2.37 NEUT (10 9 /L) 5.70±1.67 6.00±1.81 LYM (10 9 /L) 2.50±0.75 2.61±0.73 CRP (mg/L) ** 12.45±3.99 8.99±2.52 LDH (U/L) ** 334.06±104.26 288.61±63.01 D-dimer (μg/ml) ** 0.60±0.16 0.40±0.13 ** P<0.05 Comparison of treatments and chest images between MPP patients infected with MRMP and MSMP The treatment and diagnosis results, including hospitalization days, the rate of lung consolidation, and the frequencies of bronchoscope use and second-line antibiotic use, are summarized in Table 3. According to the statistical results, the duration of hospitalization was longer in the MPP patients caused by MRMP than in the MSMP patients (P<0.05); the rate of lung consolidation and the frequencies of bronchoscope use and second-line antibiotic use were greater in the MRMP group than in the MSMP patients (P<0.05). Table 3 Treatment and imaging results Group MRMP MSMP Hospitalized days ** 8.93±1.81 7.89±2.02 Rate of lung consolidation ** 50/50 24/55 Frequency of bronchoscope use ** 50/50 20/55 Frequency of second-line antibiotics use ** 36/50 26/55 ** P<0.05 Discussion In the present study, we investigated and compared the laboratory test results, imaging results from chest CT and treatment results between MMP patients caused by MRMP and MSMP. We found that MRMP patients could be more difficult to treat because of their longer hospitalization duration, greater frequency of second-line antibiotic use and bronchoscope use; additionally, MRMP could be more severe because of its greater inflammatory markers, including CRP and LDH levels and D-dimer levels, and greater rate of lung consolidation. The tests for M. pneumoniae infection include culture, serologic tests and PCR; among these tests, RT–PCR is the most reliable because of its high accuracy and speed and because it can be used for current infection tests[16]. Therefore, we applied an RNA test for the detection of M. pneumoniae infection in our study. The macrolide resistance of M. pneumoniae was diagnosed by RT‒PCR tests targeting the A2063G and A2064G mutations, which account for nearly all macrolide resistance-associated mutations in China and are correlated with a high level of macrolide resistance[17-18]. Lung consolidation has predictive value in RMPP[19], and the rate of lung consolidation observed in patients with MPP caused by MRMP was greater than that in patients with MSMP, suggesting that MRMP was more likely to lead to RMPP. The prevalence of MRMP has placed a serious burden on the health of children, which could cause prolonged fever and radiological progression. MRMP is the main cause of increased RMPP in children. Due to the decreased efficacy of conventional macrolide antibiotics and increased pathogen load, the body will experience an excessive immune response to pathogens, which results in damage[4]. The inflammatory markers CRP and LDH were increased in MRMP-infected patients, which could reflect the increased intensity of inflammation caused by MRMP. According to the study by Jeong JE et al.[20], the levels of CRP and LDH were greater in MPP patients with prolonged fever, which was similar to our findings in MRMP patients with longer disease courses. D-dimer levels are closely related to the inflammatory response and may reflect the coagulation status of infectious diseases[21]. D-dimer levels are usually greater in severe MMP patients than in mild patients, and elevated serum D-dimer levels might be used as an indicator of the severity of MPP[22]. The D-dimer levels in MRMP-infected MPP patients were greater than those in MPP patients caused by MSMP, suggesting that MRMP could cause more severe MPP than MSMP. We found no significant differences in WBC, NEUT or LYM counts between MRMP- and MSMP-infected MPP patients, suggesting that the WBC count and differentiation status were not correlated with the MRMP or the severity of MPP, which was in accordance with the findings of previous studies by Fan F et al.[19]. A bronchoscope was used for the treatment of the majority of the MPP patients in our study. Due to the self-limiting nature of MPP, bronchoscopy is an effective procedure for treating this disease, and it can aid in the relief of symptoms and recovery of patients. A bronchoscope was regularly used for the treatment of MPP patients in our study, especially for patients with MRMP-caused MPP, suggesting the important clinical value of bronchoscopy. There were more hospitalization days for MPP patients caused by MRMP than for MSMP patients; therefore, MRMP could increase the disease course during treatment, and these results are consistent with those of a previous study by Yang HJ et al.[23]. Corticosteroids are immune modulators used to treat MPP, and they can be used to control lung injuries caused by initial hyperactive immune reactions. Therefore, corticosteroids were used for most of the MPP patients (MRMP or MSMP) in our study. The effect of corticosteroids on immune cells is dose dependent, and the dose of corticosteroids can be adjusted according to the severity of disease[16]. Although the possibility of adverse effects in the future may exist, alternative antibiotics, including doxycycline and levofloxacin, were frequently used based on consideration of the disease severity and the agreement of the guardians of the patients in our study. The selection of second-line antibiotics was mainly based on the age of the patients in our study, but further studies are needed to compare the effects of these two kinds of alternative antibiotics. In our study, the frequency of second-line antibiotic use was greater in MRMP-caused MPP patients than in MSMP patients, supporting the reduced effect of macrolides in the treatment of MRMP infections. However, interestingly, no alternative antibiotics to azithromycin were used in 14 of the 50 MRMP-related MPP patients; similarly, 26 of the 55 MSMP patients were treated with alternative antibiotics. Macrolide has anti-inflammatory and immunoregulatory functions, suggesting that it is effective in the treatment of some MRMP-infected patients[16]. Alternative antibiotics were used in MSMP patients when macrolide use did not improve their condition or when the pneumonia worsened. The decrease in the effect of macrolides in the treatment of MSMP patients might be because macrolide resistance developed during macrolide treatment, which has been confirmed in previous studies[24]. However, the degree to which macrolide resistance develops and the duration of macrolide resistance development during macrolide treatment require additional studies. There are several limitations to our study. Although A2063G and A2064G are the predominant mutations associated with macrolide resistance and almost no other mutations have been discovered in this district, the possibility that other macrolide resistance-associated mutations might exist during our study and might influence our diagnosis and treatment cannot be excluded. Conclusion MRMP could increase the severity of MPP according to worse laboratory test results and chest CT examination results, and MRMP-infected MPP patients might be more difficult to treat due to the longer hospitalization days, higher rate of bronchoscope use and second-line antibiotic use. Abbreviations M. pneumoniae Mycoplasma pneumoniae ; CAP community-acquired pneumonia; MPP M. pneumoniae pneumonia; MRMP macrolide-resistant M. pneumoniae ; RMPP refractory MPP; WBC white blood cell count; CRP C-reactive protein; LDH lactate dehydrogenase; NEUT neutrophil count; LYM lymphocyte count; MSMP macrolide-sensitive M. pneumoniae ; RT‒PCR real-time PCR; SD standard deviation. Declarations Authors’ contributions Maodong Leng conceptualized and designed the study, conducted data collection, analyses and interpretation, and drafted the initial manuscript. Zhen Dong provided advice on the study design and contributed to the data acquisition. All authors critically reviewed and revised the manuscript. All authors approved the final manuscript and agree to be accountable for all aspects of the work. Availability of data and materials The data that support the findings of this study are available from the corresponding author upon reasonable request. Ethics approval This retrospective study was conducted on already available data and was approved by the Medical Ethics Committee of the Children’s Hospital Affiliated to Zhengzhou University institutional review board and conducted under the Declaration of Helsinki principles . Consent to participate Informed consent was obtained from the legal guardians of all participants included in the study. Funding This work was supported by Medical Science and Technology Project of Henan Province (LHGJ20220738). Competing interests The authors declare no competing interests. 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Clin Respir J 17(7):607-617. https://doi:10.1111/crj.13620 Jeong JE, Soh JE, Kwak JH, et al (2018) Increased procalcitonin level is a risk factor for prolonged fever in children with Mycoplasma pneumonia. Korean J Pediatr 61(8):258-263. https://doi:10.3345/kjp.2018.61.8.258 Milenkovic M, Hadzibegovic A, Kovac M, et al (2022) D-dimer, CRP, PCT, and IL-6 Levels at Admission to ICU Can Predict In-Hospital Mortality in Patients with COVID-19 Pneumonia. Oxid Med Cell Longev 2022:8997709. https://doi:10.1155/2022/8997709 Li YT, Zhang J, Wang MZ, et al (2023) Changes in coagulation markers in children with Mycoplasma pneumoniae pneumonia and their predictive value for Mycoplasma severity. Ital J Pediatr 49(1):143. https://doi:10.1186/s13052-023-01545-1 Yang HJ (2019) Benefits and risks of therapeutic alternatives for macrolide resistant Mycoplasma pneumoniae pneumonia in children. Korean J Pediatr 62(6):199-205. https://doi:10.3345/kjp.2018.07367 Suzuki Y, Shimotai Y, Itagaki T, et al (2017) Development of macrolide resistance-associated mutations after macrolide treatment in children infected with Mycoplasma pneumoniae. J Med Microbiol 66(11):1531-1538. https://doi:10.1099/jmm.0.000582 Additional Declarations No competing interests reported. Cite Share Download PDF Status: Posted Version 1 posted 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-3897023","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":269806645,"identity":"f5277fc9-31ea-46dc-9a29-33bb21550333","order_by":0,"name":"Maodong Leng","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA4klEQVRIiWNgGAWjYBACNvmDjQ8+VNTIybM3JD5IqKghrIVPgvmw4Ywzx4wNew48Nnhw5hhhLXISbGnSnC3MiQ03HJ9JPmxhJsJh0j3GxowNbIyNM5jTKhIb2Bj427sT8GuROWP4uHCHDDO7dFvajcQdMgwSZ85uwK+FIcfYeOYZNjbGOWeAWs6wMRhI5BLUYibN28bMw3Aj/1tBYhszEVok0tJAWiQYbiSkMRCnhecwOJANgIGcLJFw5hgPQb/ItzeCo7J+PjAqP/4Axil/ey9+LRiAhzTlo2AUjIJRMAqwAgDryE3BAwtmCAAAAABJRU5ErkJggg==","orcid":"","institution":"Children’s Hospital Affiliated to Zhengzhou University, Henan Children’s Hospital","correspondingAuthor":true,"prefix":"","firstName":"Maodong","middleName":"","lastName":"Leng","suffix":""},{"id":269806646,"identity":"021fdae4-ec86-4988-8468-301b328348a2","order_by":1,"name":"Zhen Dong","email":"","orcid":"","institution":"Children’s Hospital Affiliated to Zhengzhou University, Henan Children’s Hospital","correspondingAuthor":false,"prefix":"","firstName":"Zhen","middleName":"","lastName":"Dong","suffix":""}],"badges":[],"createdAt":"2024-01-25 11:44:09","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-3897023/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-3897023/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":50560885,"identity":"ea9cc4af-1094-4417-ad7f-03f7e5642163","added_by":"auto","created_at":"2024-02-02 14:07:20","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":263992,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-3897023/v1/3da0c098-438a-44c6-be58-c7b38a3a6aab.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Comparison of laboratory test results and treatments between macrolide-resistant and macrolide-sensitive Mycoplasma pneumoniae pneumonia in children","fulltext":[{"header":"What is Known","content":"\u003cp\u003e\u003cem\u003eMacrolide-resistant Mycoplasma pneumoniae strains have emerged and developed rapidly in recent years, placing greater burdens on the treatment of these infections in children.\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eThe lack of knowledge about laboratory tests and treatments requires additional clinical investigation.\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eWhat is New:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eWe retrospectively analyzed and compared the laboratory and imaging results and treatments for macrolide-resistant and macrolide-sensitive mycoplasma pneumoniae pneumonia in a Chinese pediatric cohort.\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eOur work may improve the understanding of macrolide-resistant Mycoplasma pneumoniae-related laboratory test results and treatments for pneumonia patients.\u003c/em\u003e\u003c/p\u003e"},{"header":"Introduction","content":"\u003cp\u003e\u003cem\u003eMycoplasma pneumoniae\u003c/em\u003e (\u003cem\u003eM.\u0026nbsp;\u003c/em\u003e\u003cem\u003epneumoniae\u003c/em\u003e) is one of the main causes of community-acquired pneumonia (CAP) and is responsible for 10-40% of CAPs[1]. \u003cem\u003eM. pneumoniae\u0026nbsp;\u003c/em\u003epneumonia (MPP) can affect people of any age but is most common in children. Since it was first isolated and reported in Japan[2], macrolide-resistant \u003cem\u003eM. pneumoniae\u0026nbsp;\u003c/em\u003e(MRMP) infection has developed rapidly worldwide. The increase in the MPP caused by MRMP has increased the difficulty in treating due to the reduced effects of macrolides, and an increasing number of refractory MPPs (RMPPs) are being identified in pediatric patients.\u003c/p\u003e\n\u003cp\u003eMRMP has been caused by the wide and inappropriate use of macrolides in recent years, and macrolide resistance has reached 80-90% in China according to previous studies[3-5]. Previous studies revealed that single-point nucleotide mutations occurring in the V region of the 23S rRNA of the \u003cem\u003eM. pneumoniae\u0026nbsp;\u003c/em\u003egenome correlate with macrolide resistance[6]. The macrolide resistance-related mutations mainly occur at sites 2063, 2064, 2617 and 2067, among which 2063 and 2064 were the predominant macrolide resistance sites[7-9]. Mutations at sites 2063 and 2064 usually cause high levels of macrolide resistance, whereas mutations at sites 2617 and 2067 result in low levels of macrolide resistance[10].\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eM.\u0026nbsp;\u003c/em\u003e\u003cem\u003epneumoniae\u0026nbsp;\u003c/em\u003eis naturally resistant to \u0026beta;-lactam antibiotics because of cell wall deficiency. Tetracycline\u0026nbsp;can cause tooth staining and enamel hypoplasia and can cause gastrointestinal irritation, liver toxicity and other side effects; therefore, its use is prohibited in children aged less than 8 years. Quinolones are prohibited for use in children because they can cause cartilage and joint damage and affect bone development. Macrolides are regarded as first-line treatments for \u003cem\u003eM. pneumoniae\u0026nbsp;\u003c/em\u003einfections in children due to their low side effects and high intracellular concentrations. Because the effects of macrolides on the treatment of MPP caused by MRMP are limited, doxycycline and levofloxacin are considered alternative treatments and have achieved effective outcomes[11-13]. The use of corticosteroids in MPP treatment could prohibit the inflammatory process by modulating immunity[14]. The intensity of inflammation is usually reflected by laboratory test parameters such as the white blood cell (WBC) count, C-reactive protein (CRP) level and lactate dehydrogenase (LDH) level. D-dimer is the most important indicator of thrombogenesis and thrombolytic activity, and D-dimer can be elevated in pulmonary infections[15].\u003c/p\u003e\n\u003cp\u003eIn this study, we investigated laboratory test results, including WBC, CRP, LDH, D-dimer, neutrophil count (NEUT) and lymphocyte count (LYM), in MRMP-infected and macrolide-sensitive \u003cem\u003eM. pneumoniae\u0026nbsp;\u003c/em\u003e(MSMP) MPP patients. Treatment parameters, including antibiotic use, hospitalization duration and bronchoscopic use, were also studied for these two kinds of patients. This study will provide better knowledge of MPP caused by MRMP and MSMP and aid in future diagnosis and treatment.\u003c/p\u003e"},{"header":"Methods","content":"\u003cp\u003e\u003cstrong\u003eStudy subjects\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe study subjects were recruited randomly from among the children hospitalized for MPP at the Children\u0026rsquo;s Hospital Affiliated to Zhengzhou University from December 2023 to January 2024. Patients with coinfections of other pathogens, such as influenza virus, syncytial virus, adenovirus and bacteria other than\u003cem\u003e\u0026nbsp;M. pneumoniae,\u0026nbsp;\u003c/em\u003ewere excluded from the study. Patients with basic diseases of other body systems except the respiratory system were also not considered. Population characteristics, including age and sex, were recorded, and written informed consent was obtained from all the patients or their guardians.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eDiagnosis, imaging examination, laboratory tests and treatments\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eM. pneumoniae\u003c/em\u003e infection and macrolide resistance were tested via real-time PCR (RT\u0026ndash;PCR). Throat swab specimens were collected from the children and kept in specialized tubes with fluids for DNA and RNA extraction. RNA was extracted and then tested for \u003cem\u003eM. pneumoniae\u0026nbsp;\u003c/em\u003einfection with commercial kits according to the manufacturer\u0026rsquo;s instructions. RT‒PCR tests targeting the A2063G and A2064G mutations in region V of the 23S rRNA gene of \u003cem\u003eM. pneumoniae\u0026nbsp;\u003c/em\u003ewere applied to test macrolide resistance. Pneumonia was diagnosed by chest CT, and the presence of lung consolidation was considered. Routine blood tests were performed for all the patients, and whole peripheral blood was collected for analysis via an automatic blood cell analyzer, which could detect CRP levels at the same time. CRP, WBC, NEUT and LYM were recorded from the routine blood test results. For the biochemical analysis of LDH and D-dimer levels, peripheral blood was collected into pro-coagulation and sodium citrate anticoagulant tubes, respectively, and the serum and plasma were separated via centrifugation. The MPP patients were treated with antibiotics (azithromycin, doxycycline and levofloxacin), bronchoscopy and other regular treatments. Second-line antibiotic treatment was considered if the symptoms did not improve with the use of macrolides or if the patient had severe MPP directly confirmed by MRMP. We focused on patient treatments, including hospitalization days, frequency of bronchoscope use and second-line antibiotic use.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eStatistical analysis\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe statistical analysis in the study was completed with the use of IBM SPSS Statistics 21. Quantitative data are expressed as the mean \u0026plusmn; standard deviation (SD) to demonstrate the average value and variation, and\u0026nbsp;Student\u0026rsquo;s \u003cem\u003et\u003c/em\u003e test was used for comparisons between two groups.\u0026nbsp;For qualitative data, the chi-square test was performed for comparisons between two groups. P\u0026lt;0.05 was considered to indicate statistical significance.\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003e\u003cstrong\u003ePopulation characteristics\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eIn the present study, 50 MRMP-infected MPP patients and 55 MSMP-infected patients were included. The number of male and female children in each group and the ages of the study subjects are shown in Table 1. There was no significant difference with regard to age or sex between MRMP- and MSMP-infected patients.\u003c/p\u003e\n\u003cp\u003eTable 1 Sex and ages of the study subjects\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd width=\"33.333333333333336%\" valign=\"top\"\u003e\n \u003cp\u003eGroup\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"33.333333333333336%\" valign=\"top\"\u003e\n \u003cp\u003eMRMP\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"33.333333333333336%\" valign=\"top\"\u003e\n \u003cp\u003eMSMP\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"33.333333333333336%\" valign=\"top\"\u003e\n \u003cp\u003eSex (male/female)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"33.333333333333336%\" valign=\"top\"\u003e\n \u003cp\u003e28/22\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"33.333333333333336%\" valign=\"top\"\u003e\n \u003cp\u003e27/28\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"33.333333333333336%\" valign=\"top\"\u003e\n \u003cp\u003eAge (years, mean\u0026plusmn; SD)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"33.333333333333336%\" valign=\"top\"\u003e\n \u003cp\u003e6.81\u0026plusmn;2.06\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"33.333333333333336%\" valign=\"top\"\u003e\n \u003cp\u003e6.34 \u0026plusmn;1.94\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003cstrong\u003eLaboratory test results\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe laboratory test results, including WBC, NEUT, LYM, LDH, D-dimer and CRP levels, are shown in Table 2. The LDH, D-dimer and CRP levels were significantly greater in the MRMP-infected MPP patients than in the MSMP patients (P\u0026lt;0.05); however, WBC, NEUT and LYM were not significantly different between the two groups (P\u0026gt;0.05).\u003c/p\u003e\n\u003cp\u003eTable 2 Laboratory test results for MRMP- and MSMP-infected patients (mean\u0026plusmn; SD)\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd width=\"33.333333333333336%\" valign=\"top\"\u003e\n \u003cp\u003eGroup\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"33.333333333333336%\" valign=\"top\"\u003e\n \u003cp\u003eMRMP\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"33.333333333333336%\" valign=\"top\"\u003e\n \u003cp\u003eMSMP\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"33.333333333333336%\" valign=\"top\"\u003e\n \u003cp\u003eWBC (10\u003csup\u003e9\u003c/sup\u003e/L)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"33.333333333333336%\" valign=\"top\"\u003e\n \u003cp\u003e8.35\u0026plusmn;2.36\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"33.333333333333336%\" valign=\"top\"\u003e\n \u003cp\u003e8.96\u0026plusmn;2.37\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"33.333333333333336%\" valign=\"top\"\u003e\n \u003cp\u003eNEUT (10\u003csup\u003e9\u003c/sup\u003e/L)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"33.333333333333336%\" valign=\"top\"\u003e\n \u003cp\u003e5.70\u0026plusmn;1.67\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"33.333333333333336%\" valign=\"top\"\u003e\n \u003cp\u003e6.00\u0026plusmn;1.81\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"33.333333333333336%\" valign=\"top\"\u003e\n \u003cp\u003eLYM (10\u003csup\u003e9\u003c/sup\u003e/L)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"33.333333333333336%\" valign=\"top\"\u003e\n \u003cp\u003e2.50\u0026plusmn;0.75\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"33.333333333333336%\" valign=\"top\"\u003e\n \u003cp\u003e2.61\u0026plusmn;0.73\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"33.333333333333336%\" valign=\"top\"\u003e\n \u003cp\u003eCRP (mg/L)\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"33.333333333333336%\" valign=\"top\"\u003e\n \u003cp\u003e12.45\u0026plusmn;3.99\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"33.333333333333336%\" valign=\"top\"\u003e\n \u003cp\u003e8.99\u0026plusmn;2.52\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"33.333333333333336%\" valign=\"top\"\u003e\n \u003cp\u003eLDH (U/L)\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"33.333333333333336%\" valign=\"top\"\u003e\n \u003cp\u003e334.06\u0026plusmn;104.26\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"33.333333333333336%\" valign=\"top\"\u003e\n \u003cp\u003e288.61\u0026plusmn;63.01\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"33.333333333333336%\" valign=\"top\"\u003e\n \u003cp\u003eD-dimer (\u0026mu;g/ml)\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"33.333333333333336%\" valign=\"top\"\u003e\n \u003cp\u003e0.60\u0026plusmn;0.16\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"33.333333333333336%\" valign=\"top\"\u003e\n \u003cp\u003e0.40\u0026plusmn;0.13\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003csup\u003e**\u003c/sup\u003eP\u0026lt;0.05\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eComparison of treatments and chest images between MPP patients infected with MRMP and MSMP\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe treatment and diagnosis results, including hospitalization days, the rate of lung consolidation, and the frequencies of bronchoscope use and second-line antibiotic use, are summarized in Table 3. According to the statistical results, the duration of hospitalization was longer in the MPP patients caused by MRMP than in the MSMP patients (P\u0026lt;0.05); the rate of lung consolidation and the frequencies of bronchoscope use and second-line antibiotic use were greater in the MRMP group than in the MSMP patients (P\u0026lt;0.05).\u003c/p\u003e\n\u003cp\u003eTable 3 Treatment and imaging results\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd width=\"51.40845070422535%\" valign=\"top\"\u003e\n \u003cp\u003eGroup\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25%\" valign=\"top\"\u003e\n \u003cp\u003eMRMP\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.591549295774648%\" valign=\"top\"\u003e\n \u003cp\u003eMSMP\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"51.40845070422535%\" valign=\"top\"\u003e\n \u003cp\u003eHospitalized days\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25%\" valign=\"top\"\u003e\n \u003cp\u003e8.93\u0026plusmn;1.81\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.591549295774648%\" valign=\"top\"\u003e\n \u003cp\u003e7.89\u0026plusmn;2.02\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"51.40845070422535%\" valign=\"top\"\u003e\n \u003cp\u003eRate of lung consolidation\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25%\" valign=\"top\"\u003e\n \u003cp\u003e50/50\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.591549295774648%\" valign=\"top\"\u003e\n \u003cp\u003e24/55\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"51.40845070422535%\" valign=\"top\"\u003e\n \u003cp\u003eFrequency of bronchoscope use\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25%\" valign=\"top\"\u003e\n \u003cp\u003e50/50\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.591549295774648%\" valign=\"top\"\u003e\n \u003cp\u003e20/55\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"51.40845070422535%\" valign=\"top\"\u003e\n \u003cp\u003eFrequency of second-line antibiotics use\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25%\" valign=\"top\"\u003e\n \u003cp\u003e36/50\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.591549295774648%\" valign=\"top\"\u003e\n \u003cp\u003e26/55\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003csup\u003e**\u003c/sup\u003eP\u0026lt;0.05\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eIn the present study, we investigated and compared the laboratory test results, imaging results from chest CT and treatment results between MMP patients caused by MRMP and MSMP. We found that MRMP patients could be more difficult to treat because of their longer hospitalization duration, greater frequency of second-line antibiotic use and bronchoscope use; additionally, MRMP could be more severe because of its greater inflammatory markers, including CRP and LDH levels and D-dimer levels, and greater rate of lung consolidation.\u003c/p\u003e\n\u003cp\u003eThe tests for \u003cem\u003eM. pneumoniae\u003c/em\u003e infection include culture, serologic tests and PCR; among these tests, RT\u0026ndash;PCR is the most reliable because of its high accuracy and speed and because it can be used for current infection tests[16]. Therefore, we applied an RNA test for the detection of \u003cem\u003eM. pneumoniae\u003c/em\u003e infection in our study. The macrolide resistance of \u003cem\u003eM. pneumoniae\u0026nbsp;\u003c/em\u003ewas diagnosed by RT‒PCR tests targeting the A2063G and A2064G mutations, which account for nearly all macrolide resistance-associated mutations in China and are correlated with a high level of macrolide resistance[17-18]. Lung consolidation has predictive value in RMPP[19], and the rate of lung consolidation observed in patients with MPP caused by MRMP was greater than that in patients with MSMP, suggesting that MRMP was more likely to lead to RMPP.\u003c/p\u003e\n\u003cp\u003eThe prevalence of MRMP has placed a serious burden on the health of children, which could cause prolonged fever and radiological progression. MRMP is the main cause of increased RMPP in children. Due to the decreased efficacy of conventional macrolide antibiotics and increased pathogen load, the body will experience an excessive immune response to pathogens, which results in damage[4]. The inflammatory markers CRP and LDH were increased in MRMP-infected patients, which could reflect the increased intensity of inflammation caused by MRMP. According to the study by Jeong JE et al.[20], the levels of CRP and LDH were greater in MPP patients with prolonged fever, which was similar to our findings in MRMP patients with longer disease courses. D-dimer levels are closely related to the inflammatory response and may reflect the coagulation status of infectious diseases[21]. D-dimer levels are usually greater in severe MMP patients than in mild patients, and elevated serum D-dimer levels might be used as an indicator of the severity of MPP[22]. The D-dimer levels in MRMP-infected MPP patients were greater than those in MPP patients caused by MSMP, suggesting that MRMP could cause more severe MPP than MSMP. We found no significant differences in WBC, NEUT or LYM counts between MRMP- and MSMP-infected MPP patients, suggesting that the WBC count and differentiation status were not correlated with the MRMP or the severity of MPP, which was in accordance with the findings of previous studies by\u0026nbsp;Fan F et al.[19].\u003c/p\u003e\n\u003cp\u003eA bronchoscope was used for the treatment of the majority of the MPP patients in our study. Due to the self-limiting nature of MPP, bronchoscopy is an effective procedure for treating this disease, and it can aid in the relief of symptoms and recovery of patients. A bronchoscope was regularly used for the treatment of MPP patients in our study, especially for patients with MRMP-caused MPP, suggesting the important clinical value of bronchoscopy. There were more hospitalization days for MPP patients caused by MRMP than for MSMP patients; therefore, MRMP could increase the disease course during treatment, and these results are consistent with those of a previous study by\u0026nbsp;Yang HJ\u0026nbsp;et al.[23].\u0026nbsp;Corticosteroids are immune modulators used\u0026nbsp;to treat MPP, and\u0026nbsp;they\u0026nbsp;can be used to control lung injuries\u0026nbsp;caused by\u0026nbsp;initial hyperactive immune reactions. Therefore,\u0026nbsp;corticosteroids were\u0026nbsp;used for most of\u0026nbsp;the MPP patients (MRMP or MSMP) in our study. The effect of\u0026nbsp;corticosteroids\u0026nbsp;on immune cells is dose dependent, and the dose of\u0026nbsp;corticosteroids\u0026nbsp;can be adjusted according to the severity of disease[16]. Although the possibility of adverse effects in the future may exist, alternative antibiotics,\u0026nbsp;including\u0026nbsp;doxycycline and levofloxacin,\u0026nbsp;were frequently used based on consideration of the disease severity and the\u0026nbsp;agreement\u0026nbsp;of the guardians of the patients in our study. The selection of second-line antibiotics was mainly\u0026nbsp;based on\u0026nbsp;the\u0026nbsp;age\u0026nbsp;of the patients in our study, but further studies are needed to compare the effects of\u0026nbsp;these\u0026nbsp;two kinds of alternative antibiotics. In our study, the frequency of second-line\u0026nbsp;antibiotic\u0026nbsp;use was\u0026nbsp;greater\u0026nbsp;in MRMP-caused MPP patients than in MSMP patients, supporting the reduced effect of\u0026nbsp;macrolides\u0026nbsp;in the\u0026nbsp;treatment\u0026nbsp;of MRMP infections.\u0026nbsp;However,\u0026nbsp;interestingly, no alternative antibiotics to\u0026nbsp;azithromycin\u0026nbsp;were used in 14 of the 50 MRMP-related\u0026nbsp;MPP patients; similarly, 26 of the 55 MSMP patients were treated with alternative antibiotics.\u0026nbsp;Macrolide has anti-inflammatory and immunoregulatory functions, suggesting that it is effective in the treatment of some MRMP-infected patients[16]. Alternative antibiotics were used in MSMP patients when macrolide use did not improve their condition or when the pneumonia worsened. The decrease in the effect of macrolides in the treatment of MSMP patients might be because macrolide resistance developed during macrolide treatment, which has been confirmed in previous studies[24]. However, the degree to which macrolide resistance develops and the duration of macrolide resistance development during macrolide treatment require additional studies.\u003c/p\u003e\n\u003cp\u003eThere are several limitations to our study. Although A2063G and A2064G are the predominant mutations associated with macrolide resistance and almost no other mutations have been discovered in this district, the possibility that other macrolide resistance-associated mutations might exist during our study and might influence our diagnosis and treatment cannot be excluded.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eMRMP could increase the severity of MPP according to worse laboratory test results and chest CT examination results, and MRMP-infected MPP patients might be more difficult to treat due to the longer hospitalization days, higher rate of bronchoscope use and second-line antibiotic use.\u003c/p\u003e"},{"header":"Abbreviations","content":"\u003cp\u003e\u003cem\u003eM. pneumoniae \u0026nbsp;Mycoplasma pneumoniae\u003c/em\u003e; CAP \u0026nbsp;community-acquired pneumonia; MPP \u0026nbsp;\u003cem\u003eM. pneumoniae\u0026nbsp;\u003c/em\u003epneumonia; MRMP \u0026nbsp;macrolide-resistant \u003cem\u003eM. pneumoniae\u003c/em\u003e;\u003cem\u003e\u0026nbsp;\u003c/em\u003eRMPP \u0026nbsp;refractory MPP; WBC \u0026nbsp;white blood cell count; CRP \u0026nbsp;C-reactive protein; LDH \u0026nbsp;lactate dehydrogenase; NEUT \u0026nbsp;neutrophil count; LYM \u0026nbsp;lymphocyte count; MSMP \u0026nbsp;macrolide-sensitive \u003cem\u003eM. pneumoniae\u003c/em\u003e;\u003cem\u003e\u0026nbsp;\u003c/em\u003eRT‒PCR \u0026nbsp;real-time PCR; SD \u0026nbsp;standard deviation.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eAuthors\u0026rsquo; contributions\u003c/strong\u003e Maodong Leng conceptualized and designed the study, conducted data collection, analyses and interpretation, and drafted the initial manuscript. Zhen Dong provided advice on the study design and contributed to the data acquisition. All authors critically reviewed and revised the manuscript. All authors approved the final manuscript and agree to be accountable for all aspects of the work.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAvailability of data and materials\u0026nbsp;\u003c/strong\u003eThe data that support the findings of this study are available from the corresponding author upon reasonable request.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEthics approval\u0026nbsp;\u003c/strong\u003eThis retrospective study was conducted on already available data and was approved by the Medical Ethics Committee of the Children\u0026rsquo;s Hospital Affiliated to Zhengzhou University institutional review board and conducted under the Declaration of Helsinki principles .\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent to participate\u0026nbsp;\u003c/strong\u003eInformed consent was obtained from the legal\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eguardians of all participants included in the study.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e This work was supported by Medical Science and Technology Project of Henan Province (LHGJ20220738).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting interests\u0026nbsp;\u003c/strong\u003eThe authors declare no competing interests.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eMorozumi, M., Takahashi, T., Ubukata, K (2010) Macrolide-resistant Mycoplasma pneumoniae: characteristics of isolates and clinical aspects of community-acquired pneumonia. 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Korean J Pediatr 62(6):199-205. https://doi:10.3345/kjp.2018.07367\u003c/li\u003e\n\u003cli\u003eSuzuki Y, Shimotai Y, Itagaki T, et al (2017) Development of macrolide resistance-associated mutations after macrolide treatment in children infected with Mycoplasma pneumoniae. J Med Microbiol 66(11):1531-1538. https://doi:10.1099/jmm.0.000582\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"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":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Macrolide resistance. Mycoplasma pneumoniae. Children. Laboratory test. Treatment","lastPublishedDoi":"10.21203/rs.3.rs-3897023/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-3897023/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cem\u003eMycoplasma pneumoniae\u003c/em\u003e (\u003cem\u003eM. pneumoniae\u003c/em\u003e) is one of the main pathogens resulting in pneumonia, and macrolides are regarded as first-line treatment antibiotics for \u003cem\u003eM. pneumoniae \u003c/em\u003epneumonia (MPP). The development and widespread of macrolide-resistant \u003cem\u003eM. pneumoniae\u003c/em\u003e (MRMP) has increased the difficulty of treating MPP. This study aimed to investigate the differences in laboratory test results and treatment results between MPP caused by MRMP and macrolide-sensitive \u003cem\u003eM. pneumoniae\u003c/em\u003e (MSMP) in children. The patients were recruited from among the hospitalized children at the Children’s Hospital Affiliated to Zhengzhou University. Pneumonia was diagnosed via chest CT. The laboratory test results investigated included white blood cell (WBC) count, neutrophil count (NEUT), lymphocyte count (LYM), C-reactive protein (CRP), lactate dehydrogenase (LDH), and D-dimer; treatment results, including antibiotics used, hospitalization days and bronchoscopyuse, were also obtained. MRMP-infected MPP patients demonstrated a greater rate of lung consolidation; a greater frequency of bronchoscope use and second-line antibiotic use; higher levels of CRP, LDH and D-dimer; and more hospitalization days than MPP patients caused by MSMP. There were no differences with regard to the WBC, NEUT, or LYM counts between MRMP patients and MSMP patients.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eConclusions: \u003c/em\u003eThe worsening of MPP caused by MRMP could be more severe than that caused by MSMP because of poor laboratory and chest CT results, and MRMP infection increases the difficulty of treatment.\u003c/p\u003e","manuscriptTitle":"Comparison of laboratory test results and treatments between macrolide-resistant and macrolide-sensitive Mycoplasma pneumoniae pneumonia in children","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-01-31 05:25:02","doi":"10.21203/rs.3.rs-3897023/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"b24ebadd-65cc-4705-81f3-b193500d761a","owner":[],"postedDate":"January 31st, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2024-02-02T13:59:13+00:00","versionOfRecord":[],"versionCreatedAt":"2024-01-31 05:25:02","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-3897023","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-3897023","identity":"rs-3897023","version":["v1"]},"buildId":"qtupq5eGEP_6zYnWcrvyt","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}