Mortality Risk Factors and Clinical Profiles of Pediatric Adenovirus Pneumonia: A Study from a Comprehensive Hospital in Northeast China

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This study analyzes the clinical characteristics and key risk factors for mortality in children with ADVP admitted to a PICU in Northeast China. A total of 91 cases were reviewed, with a focus on clinical features, laboratory results, and radiological findings. In Northeast China, the incidence of ADVP peaked in autumn (34.1%) and winter (38.5%), with a PICU mortality rate of 22.9% in winter. The median onset age was 2.6 years, and the overall PICU mortality rate was 13.19%. Mortality was notably higher among children aged ≤ 2 years and those with a history of preterm birth. Clinical markers such as carbon dioxide retention, a low P/F ratio, hypoalbuminemia, elevated LDH levels, and pleural effusion were associated with increased mortality. Logistic regression identified age ≤ 2 years (OR: 24.542, 95% CI: 1.443 ~ 417.42), preterm birth (OR: 36.107, 95% CI: 1.444 ~ 903.032), and a P/F ratio < 300 mmHg (OR: 19.725, 95% CI: 1.539 ~ 252.808) as independent risk factors for mortality. These findings highlight the need for early risk identification and targeted interventions in high-risk pediatric groups to improve outcomes. Adenovirus pneumonia Pediatric Mortality Risk factors PaO2/FiO2 ratio Preterm birth Figures Figure 1 Figure 2 Figure 3 1 Introduction The 21st century has witnessed several viral epidemics that present significant public health challenges globally. In China, outbreaks of severe acute respiratory syndrome (SARS), avian influenza (H5N1), influenza A (H1N1), hand, foot, and mouth disease (EV71), and the recent COVID-19 pandemic highlighted the impact of viral diseases on healthcare systems [ 1 – 5 ] . Among these viruses, human adenovirus (HAdV) has emerged as a significant pathogen known for its highly contagious nature and ability to cause a broad spectrum of clinical symptoms, such as respiratory tract infections, conjunctivitis, gastroenteritis, and urinary tract infections [ 6 ] . Although HAdV infections are generally self-limiting, they can lead to severe adenovirus pneumonia (ADVP) in pediatric populations, which is often associated with high morbidity and mortality [ 7 ] . Unlike other community-acquired pneumonias (CAP), such as Mycoplasma and Staphylococcus aureus pneumonia, severe adenovirus pneumonia (SAP) is difficult to diagnose in its early stages because of the nonspecific clinical symptoms and the underdeveloped immune system in children, particularly their humoral immunity, which contributes to the high mortality rate [ 8 ] . The lack of specific antiviral treatments further complicates management, often leaving supportive care as the primary intervention. Given its severity, SAP is a frequent cause of admission to pediatric intensive care units (PICUs), where the primary challenge lies in early identification and intervention to prevent fatal outcomes. Despite extensive research on ADVP, a critical gap remains in the early identification of SAP risk factors at the time of PICU admission. Early identification of high-risk patients, especially within the first 24 hours of PICU admission, is crucial for initiating timely interventions that could mitigate disease progression and improve survival rates. The diverse clinical presentations complicate the timely recognition of patients at the greatest risk of mortality. Therefore, this study aims to retrospectively analyze the clinical characteristics and identify mortality risk factors in children admitted to the PICU with adenovirus pneumonia within the first 24 hours. The findings are expected to inform more effective early management strategies, optimize resource utilization, and ultimately improve patient outcomes. 2 Materials and methods 2.1 Study population This study is a retrospective case series analysis of 91 children who were diagnosed with adenovirus pneumonia and admitted to the pediatric intensive care unit (PICU) of Shengjing Hospital of China Medical University (Northeast National Regional Pediatric Center) between January 1, 2018, and December 31, 2020. This is a noninterventional, retrospective case series. The study population consisted of all pediatric patients meeting the inclusion criteria during the specified timeframe. The inclusion criteria were as follows: (1) aged between 28 days and 14 years; (2) confirmed adenovirus infection through high-throughput genetic testing of DNA from respiratory samples (nasopharyngeal swabs, deep airway sputum, or alveolar lavage fluid) or detection of serum IgM antibodies by indirect immunofluorescence and met the diagnostic criteria for adenovirus pneumonia. The exclusion criteria were as follows: (1) incomplete medical records and (2) comorbidities such as neuromuscular diseases, inherited metabolic disorders, severe immunodeficiency, and myelosuppression associated with hematologic malignancies. The study was approved by the Ethics Committee of Shengjing Hospital (Approval number: 2022PS018K). Informed consent was waived because of the retrospective nature of the study. No specific sampling methods, such as randomization, were used, as all available cases were included for analysis. Data were extracted from medical records for each patient. 2.2 Research definitions Adenovirus pneumonia was diagnosed on the basis of a combination of clinical manifestations, radiological findings, and laboratory confirmation of adenovirus infection. The diagnostic criteria for adenovirus pneumonia followed the Diagnostic and Treatment Guidelines for Adenovirus Pneumonia in Children (2019 Edition) [9] , whereas the criteria for severe pneumonia were based on the Guidelines for the Management of Community-Acquired Pneumonia in Children (2013 Revision) [10] . Severe adenovirus pneumonia (SAP) was defined as meeting the criteria for both adenovirus pneumonia and severe pneumonia. 2.3 Research data collection Blood samples (2–5 mL) were collected from each child within 24 hours of PICU admission and immediately processed for blood gas analysis, complete blood count, biochemical tests, and assessment of inflammatory markers (e.g., CRP, PCT, and IL-6). Respiratory samples, including nasopharyngeal swabs, lower respiratory tract sputum, and alveolar lavage fluid, were collected via sterile techniques for pathogen detection via high-throughput DNA sequencing. Nasopharyngeal swabs were collected by gently inserting the swab into the nasopharynx, whereas lower respiratory tract sputum and alveolar lavage fluid were collected as needed, often via bronchoscopy. Comprehensive clinical data, including present illness, personal history (e.g., history of premature birth), past medical history (e.g., allergies, previous respiratory infections), and family history, were recorded. Detailed clinical characteristics during hospitalization, including age of onset, season of onset, presenting symptoms, peak temperature, fever duration, pulmonary signs, imaging findings, complications, and length of hospital stay, were documented. 2.4 Statistical methods Statistical analysis was conducted via IBM SPSS software (version 22.0; Armonk, NY, United States). Normally distributed continuous variables were analyzed via independent t tests, whereas nonnormally distributed variables were assessed via the Mann–Whitney U test. Categorical variables are expressed as numbers (n) and percentages (%), with continuous variables presented as medians and interquartile ranges (IQRs). Differences between groups were evaluated via the chi-square test. A multivariate analysis was performed via a stepwise logistic regression model to identify independent risk factors for mortality. A p value of less than 0.05 was considered statistically significant. 3 Results The epidemiological data for the 91 children diagnosed with adenovirus pneumonia are presented in Figs. 1 and 2. The patients’ demographic information is summarized in Table 1 , and their clinical features are detailed in Table 2 . The laboratory results and radiological findings are provided in Table 3 . Table 1 Basic characteristics of 91 children with adenovirus pneumonia Total (n = 91) n (%) Survival group (n = 79) n (%) Death group (n = 12) n (%) P-value Gender boy 60 (65.9) 52 (65.8) 9 (75.0) girl 31 (34.1) 27 (24.3) 3 (25.0) 0.764 Age, months, median(IQR) 2.6 (1.5 ~ 4) 2.8 (1.7 ~ 4) 1.3 (0.7 ~ 2) Age distribution, years ≤ 2 years old 37 (40.7) 27 (34.2) 10 (83.3) > 2 years old 54 (59.3) 52 (65.8) 2 (16.7) 0.004 History of preterm 10 (11.0) 6 (7.6) 4 (33.3) 0.031 History of allergy 33 (36.3) 30 (38.0) 3 (25.0) 0.583 History of lower respiratory tract infections 29 (31.9) 27 (34.2) 2 (16.7) 0.379 Table 2 Clinical characteristics of 91 children with adenovirus pneumonia. Total (n = 91) n (%) Survival group (n = 79) n (%) Death group (n = 12) n (%) P-value Peak Fever, ℃, median(IQR) 39.3 (38.5–39.7) 39.2 (38.5–39.7) 39.3 (38.9–39.8) (Z=-0.722)0.470 Fever duration, days, median (IQR) 7(5 ~ 12) 7(5 ~ 10) 16 (6.5 ~ 21) (Z=-2.391)0.083 hospitalization duration, days, median (IQR) 9(7 ~ 14) 8(7 ~ 11) 29 (13.5 ~ 34.5) (Z=-3.558) 0.000 Respiratory symptoms and signs cough 73 (80.2) 68 (86.1) 5 (41.7) 0.001 Wheeze 16 (17.6) 12 (15.2) 4 (33.3) 0.258 Rapid respiration * 25 (27.5) 21 (26.6) 4 (33.3) 0.888 hypoxia * 27 (29.7) 23 (29.1) 4 (33.3) 1 Triple retraction sign 28 (30.8) 23 (29.1) 5 (41.7) 0.588 lung auscultation Crackles 43 (47.3) 39 (49.4) 4 (33.3) 0.300 wheezing 27 (29.7) 21 (26.6) 6 (50.0) 0.188 Extrapulmonary manifestations on admission Neurological symptoms * 20 (22.0) 14 (17.7) 6 (50.0) 0.032 Gastrointestinal symptoms * 5 (5.5%) 4 (5.1) 1 (8.3) 1 conjunctivitis 5 (5.5%) 0 (0.0) 5 (6.3) 0.828 skin rash 3 (3.3) 2(2.5) 1 (8.3) 0.856 Note: * Tachypnea: 50 breaths/min; 1–5 years: >40 breaths/min; ≥5 years: >30 breaths/min. Hypoxia: transcutaneous oxygen saturation below 92%. Neurological symptoms: depression, irritability, irritability, convulsions, blurred consciousness, coma. Gastrointestinal symptoms: diarrhea, vomiting. Table 3 Examinational findings of 91 children with adenovirus pneumonia Total (n = 91) n (%) Survival group (n = 79) n (%) Death group (n = 12) n (%) P-value Laboratory indexes carbon dioxide retention * 9 (9.9) 5 (6.3) 4 (33.3) 0.045 P/F ratio < 300 mmHg 33 (36.3) 24 (30.4) 9 (75.0) 0.08 WBC, ×10^9/L, median (IQR) 9.5 (6.4–13.8) 9.4 (6.1–12.6) 12.6 (9.2–14.3) (Z=-1.501) 0.133 HGB, g/L, Median (IQR) 115 (106 ~ 122) 116 (109 ~ 123) 101 (97 ~ 112) (Z=-3.163) 1 PLT, ×10^9/L, median (IQR) 268 (217 ~ 348) 268 (218 ~ 322) 269 (202 ~ 392) (Z=-0.364) 0.729 CRP **, mg/L, median (IQR) 18.6 (5-51.7) 17.7 (4.5–51.1) 31.2 (11.8–90) (Z=-1.233) 0.218 PCT ** , ng/mL, median (IQR) 0.26 (0.1 to 0.9) 0.23 (0.1 to 0.7) 1.14 (0.4–6.1) (Z=-2.733) 0.362 IL-6 ** , pg/mL, median (IQR) 31.2 (9.6–75.3) 25.4 (9.6–53.6) 109.8 (44.8–287) (Z=-2.569) 0.147 hypoalbuminemia * 12 (13.2) 6 (7.6) 6 (50.0) 0.000 LDH > 600U/L 27(29.7) 20(25.3) 7(58.3) 0.046 Radiologic findings (n = 69) mottled opacity 58 (84.1) 47 (82.5) 11 (91.7) 0.720 Streak opacity 12 (17.4) 8 (14.0) 4 (33.3) 0.236 consolidation 28 (40.6) 20 (35.1) 8 (66.7) 0.089 Multi-lobe consolidation (≥ 3 lobes) 23 (33.3) 16 (28.1) 7 (58.3) 0.92 pleural effusion 10 (14.5) 4 (7.0) 6 (50.0) 0.01 Note : * Carbon dioxide retention: carbon dioxide partial pressure > 50 mmHg; P/F ratio: PaO2/FiO2; WBC: white blood cells; HGB: Hemoglobin; PLT: Platelet; CRP: C-reactive protein; PCT: procalcitonin;IL6: interleukin 6; hypoalbuminemia: albumin < 30 g/L; LDH: Lactate dehydrogenase; Normal value range of laboratory indexes in our hospital: CRP: 0 ~ 8mg/L, PCT: <0.05ng/mL, IL6: ≤7pg/mL, LDH: 125–243; Among the 91 children diagnosed with adenovirus pneumonia, 79 recovered, and 12 died, resulting in a case fatality rate of 13.19%. The main causes of death in the 12 patients were severe dyspnea (100%), ARDS (58.3%) and sepsis (41.7%). Adenovirus pneumonia was more prevalent during autumn (34.1%) and winter (38.5%), with the mortality rate peaking at 22.9% in winter (Fig. 1). Between 2018 and 2020, mortality rates significantly declined after reaching a peak of 35.2% in 2018 (P < 0.05). Similarly, morbidity rates peaked in 2019 but decreased sharply the following year, with only four cases reported in January 2020 (Fig. 2). As shown in Table 1 , the incidence of adenovirus pneumonia was greater in males (65.9%), with a median age of onset of 2.6 years. Approximately one-third of the children had a history of allergies and lower respiratory tract infections. Statistically, children born prematurely and those aged ≤ 2 years were more likely to succumb to the illness (P < 0.05). Table 2 highlights that all the children experienced fever upon admission, with a median peak temperature of 39.3°C (IQR: 38.5–39.7°C), and fever lasted for a median duration of 7 days (IQR: 5–12 days). In the group that died, the fever duration was notably longer, with a median duration of 16 days (IQR: 6.5–21 days). Hospitalization durations were significantly longer in the nonsurviving group, with a median of nearly one month. Cough was the most common respiratory symptom, observed in 73 children (80.2%), but its absence at admission was associated with a significantly greater likelihood of death (P = 0.001). Severe respiratory symptoms such as hypoxia (29.7%), rapid respiration (27.5%) and a positive triple concave sign (30.8%) were observed in both groups, but there were no statistically significant differences between the survival and death groups. Posthospitalization lung auscultation revealed crackles in 47.3% of the children and wheezing in 29.7%. Neurological symptoms were present in 20 children (22.0%), and these symptoms were significantly more common in the group that died (50.0% vs. 17.7%, P = 0.032). Gastrointestinal symptoms (such as vomiting and diarrhea) and skin manifestations (e.g., rash and conjunctivitis) were less common and were not significantly different between the groups. Table 3 indicates that, unlike those with bacterial pneumonia, children with adenoviral pneumonia did not exhibit significant increases in infection indicators (leukocytes, CRP, PCT, and IL-6) upon hospital admission. There were no statistically significant differences in hemoglobin or platelet levels between the survival and nonsurviving groups. Children with carbon dioxide retention (P = 0.045), hypoalbuminemia (P = 0.000), and elevated lactate dehydrogenase (LDH > 600 U/L) (P = 0.046) had significantly higher mortality rates. Radiological findings revealed that mottled opacity was the most common observation (84.1%), followed by consolidation (40.6%). Multilobe consolidation (involvement of ≥ 3 lobes) was present in 33.3% of the patients, and pleural effusion was significantly more common in the group that died (50.0% vs. 7.0%, P = 0.01). Multivariate analysis, which incorporates statistically significant variables from the univariate analysis into a logistic regression model, identified age ≤ 2 years (OR: 24.542, 95% CI: 1.443 ~ 417.42), preterm birth (OR: 36.107, 95% CI: 1.444 ~ 903.032), and a P/F ratio < 300 mmHg (OR: 19.725, 95% CI: 1.539 ~ 252.808) as independent risk factors for mortality in children with adenovirus pneumonia (see Table 4 and Fig. 3 for details). Table 4 Logistic regression analysis of mortality risk factors for children with adenovirus pneumonia B S.E Wals P OR 95% CI Age ≤ 2 years 3.200 1.446 4.900 0.027 24.542 1.443 ~ 417.423 preterm 3.586 1.643 4.768 0.029 36.107 1.444 ~ 903.032 Neurological symptoms 2.385 1.331 3.210 0.073 10.854 0.799 ~ 147.373 P/F ratio 600U/L 2.578 1.688 2.334 0.127 13.175 0.482 ~ 359.900 4 Discussion The findings of this study highlight several key epidemiological and clinical characteristics associated with adenovirus pneumonia (ADVP) in Northeast China. Notably, adenovirus pneumonia (ADVP) in our study was most prevalent in winter in Northeast China, with the highest mortality rates observed during this season, suggesting that healthcare providers should be particularly vigilant during the winter months. This finding contrasts with reports from southern China, where ADVP incidence peaks in spring and summer [ 11 ] , and differs from patterns observed in other countries [ 12 ] . This phenomenon is likely related to the circulation of various adenovirus subtypes in different regions, as different subtypes can exhibit distinct epidemiological traits, including transmissibility and virulence [ 13 ] . SAP syndrome and acute respiratory distress syndrome are typically associated with HAdV types 3, 7, 14, 21, and 55, which are more prevalent among immunocompromised individuals, particularly infants and young children aged 6 to 24 months [ 7 , 8 ] . Unfortunately, our study did not include adenovirus subtype identification. The overall PICU mortality rate for adenovirus pneumonia patients was 13.19%. This rate may be high, as data from children treated in general wards with less severe adenovirus infections were not included. Notably, our study revealed a sharp decline in PICU admissions for adenovirus pneumonia in 2020. This trend coincides with the onset of the coronavirus disease 2019 (COVID-19) pandemic, which originated in Wuhan, China, in December 2019 and led to significant changes in public behavior. Several studies [ 14 – 16 ] have demonstrated that strict respiratory protection measures and restrictions on crowd activities significantly impact the transmission dynamics of adenovirus. Although our study's sample size is limited, our findings align with these conclusions. Additionally, evidence [ 17 ] suggests that as COVID-19 restrictions are relaxed, the prevalence of non-SARS-CoV-2 respiratory viruses, including adenovirus, may increase. Given that adenovirus pneumonia outbreaks have been reported in various regions of China, including Beijing, Chongqing, Guangzhou, and Taiwan, from 2011–2018 [ 18 – 21 ] , vigilance against the potential resurgence of adenovirus infections in Shenyang is needed. Therefore, we should increase education on respiratory protection for children, especially during the winter season. One of the most critical findings from this study is the identification of specific risk factors for mortality in children with ADVP. The multivariate analysis revealed that age ≤ 2 years, preterm birth, and a P/F ratio < 300 mmHg were independent predictors of mortality. Our results align with those of previous studies that identified age ≤ 2 years as a significant risk factor for SAP and associated mortality [ 13 , 22 , 23 ] . Our findings further suggest that even premature infants older than 28 days are at elevated risk of death due to adenovirus pneumonia. Pediatric airways differ markedly from those of adults, particularly in the first two years of life [ 24 ] . Infants with narrower, more pliable airways are more susceptible to increased airflow resistance during adenovirus infections. Inflammation and secretions can easily obstruct these airways, but their immature alveolar and bronchial systems lack effective collateral ventilation, leading to compromised gas exchange in parts of the lung and resulting in severe respiratory distress [ 24 ] . Additionally, infants' limited respiratory reserve and underdeveloped, fatigue-prone respiratory muscles, especially in preterm infants, further increase the risk of respiratory muscle fatigue, which can result in severe respiratory distress and potentially death [ 24 ] . Furthermore, our findings indicate that even premature infants older than 28 days face an elevated risk of death due to adenovirus pneumonia. Pediatric airways differ significantly from those of adults, particularly during the first two years of life [ 25 ] . In immunocompromised individuals, dissemination of the virus and/or severe respiratory failure can develop in 10 to 30% of ADVP cases [ 13 ] . Our study revealed that mottled opacity (84.1%) and consolidation (40.6%) are common in patients with adenovirus pneumonia. The incidence of pleural effusion significantly differed between the survival and death groups (P < 0.05), indicating that in children with adenovirus pneumonia, infection often leads to extensive lung inflammation, resulting in alveolar filling with fluid, debris, and inflammatory cells. This process significantly impairs gas exchange, reducing the effective surface area available for oxygen transfer from the alveoli to the bloodstream. The PaO2/FiO2 (P/F) ratio has traditionally served as an indicator of lung injury and can be used to quantify the gas exchange capacity at the alveolar surface [ 26 ] . It is a variable included in most pediatric severity of illness scores [ 27 – 29 ] . A P/F ratio < 300 mmHg indicates severe impairment of oxygen exchange. Our study highlights that the P/F ratio at admission strongly correlates with mortality. This finding is significant because a low P/F ratio serves not only as a marker of disease severity but also as an important prognostic factor for identifying children at high risk of mortality. Moreover, the persistence of a low P/F ratio despite oxygen therapy suggests refractory hypoxemia, a condition that often necessitates advanced interventions such as mechanical ventilation or extracorporeal membrane oxygenation (ECMO). The concept that ventilators can both rescue and harm children is not new. Research has shown that invasive mechanical ventilation is an independent risk factor for death in SAP patients [ 25 ] . This phenomenon is related not only to alveolar epithelial injury induced by adenovirus but also to hyperoxia or mechanical stretching by the ventilator [ 30 ] . The clinical implications of these findings are significant, particularly for the management of high-risk pediatric patients with adenovirus pneumonia. Identifying young age, prematurity, and a low P/F ratio as key risk factors for mortality underscores the need for heightened surveillance and early, aggressive intervention in these populations. Clinicians should be particularly vigilant in monitoring respiratory function in young children and preterm infants with ADVP, as early signs of hypoxemia may necessitate prompt escalation of care, including consideration of advanced respiratory support techniques. This study provides valuable insights into the clinical characteristics and mortality risk factors for adenovirus pneumonia (ADVP) in Northeast China, a region where epidemiological data on ADVP are relatively scarce compared with those from southern China, which are more extensively studied. Despite these contributions, our study has certain limitations that must be acknowledged. The most significant limitation is the relatively small sample size, which may limit the generalizability of our findings. Additionally, the inability to subtype the adenovirus strains in this study restricted our ability to analyze the specific epidemiological and clinical variations attributable to different adenovirus subtypes. Furthermore, as a comprehensive hospital, patients older than 14 years are transferred to adult wards for treatment. As a result, we do not have data for children aged 14 to 18 years, which limits the scope of our findings to younger pediatric populations. This age-related data gap may lead to the overlooking of important clinical characteristics and risk factors that are relevant to older adolescents with adenovirus pneumonia. Given these limitations, future research should aim to include larger, multicenter cohorts to validate and expand upon our findings. Furthermore, incorporating molecular diagnostic techniques to identify specific adenovirus subtypes could provide a more detailed understanding of the epidemiological patterns and clinical outcomes associated with different strains. These studies are crucial for developing targeted interventions and improving the management of adenovirus pneumonia in pediatric populations across various geographic regions. Moreover, investigating the influence of early intervention strategies on outcomes in children with low P/F ratios could provide critical insights into how best to manage high-risk patients. These strategies could include the use of noninvasive ventilation, early initiation of corticosteroids or antiviral therapies, and supportive care measures such as fluid management and nutritional support. Understanding the timing and effectiveness of these interventions could lead to improved protocols and better survival rates for children with adenovirus pneumonia. Further studies should also investigate the long-term outcomes of children who survive adenovirus pneumonia, particularly those who require mechanical ventilation or other advanced respiratory support. Understanding the potential for long-term respiratory or neurological sequelae could inform follow-up care and rehabilitation strategies for these patients. Given the impact of public health measures on viral transmission, future studies could also explore the interplay between these measures and the incidence of adenovirus infections, providing insights into how best to prevent future outbreaks. 5 Conclusion This study revealed that age ≤ 2 years, a history of preterm birth, and a low PaO2/FiO2 (P/F) ratio at admission are significant independent risk factors for mortality in patients with adenovirus pneumonia. These findings underscore the critical importance of early recognition and prompt intervention in these high-risk pediatric populations. Given the high mortality rates associated with these risk factors, healthcare providers should prioritize the early identification of these vulnerable groups upon their admission to the Pediatric Intensive Care Unit (PICU). Additionally, the research underscores the need for heightened vigilance during the winter months when adenovirus pneumonia incidence and mortality rates peak. Despite limitations such as a relatively small sample size and the lack of data for adolescents aged 14 to 18 years, this study contributes valuable insights into the epidemiology and management of severe adenovirus pneumonia in children, particularly in Northeast China. Declarations Ethics approval and consent to participate The study was approved by the Ethics Committee of Shengjing Hospital (Approval number: 2022PS018K). Informed consent was waived because of the retrospective nature of the study. Consent for publication Not applicable Availability of data and materials The datasets analysed during the current study are available from the corresponding author on reasonable request Competing interests The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as potential conflicts of interest Funding The authors received no financial support for the research, authorship, or publication of this article Authors' contributions Y.S. designed the study, collected the data and drafted the manuscript. W.S. and W.X. supervised the study and revised the manuscript critically for important intellectual content. All the authors read and approved the final manuscript. Authorship Y.S. designed the study, collected the data and drafted the manuscript. W.S. and W.X. supervised the study and revised the manuscript critically for important intellectual content. All the authors read and approved the final manuscript. 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Comparative study of clinical and epidemiological characteristics of major pediatric adenovirus epidemics in southern Taiwan. BMC Infect Dis. 2019 Aug 1;19(1):681. Reintam Blaser A, Malbrain MLNG, Starkopf J, Fruhwald S, Jakob SM, De Waele J, et al. Gastrointestinal function in intensive care patients: terminology, definitions and management. Recommendations of the ESICM Working Group on Abdominal Problems. Intensive Care Med. 2012;38(3):384-94. Ghanaiem H, Averbuch D, Koplewitz BZ, Yatsiv I, Braun J, Dehtyar N, et al. An outbreak of adenovirus type 7 in a residential facility for severely disabled children. Pediatr Infect Dis J. 2011;30(11):948-52. Di Cicco M, Kantar A, Masini B, Nuzzi G, Ragazzo V, Peroni D. Structural and functional development in airways throughout childhood: Children are not small adults. Pediatr Pulmonol. 2021;56(1):240-51. Wang X, Tan X, Li Q. The difference in clinical features and prognosis of severe adenoviral pneumonia in children of different ages. J Med Virol. 2022;94(7):3303-11. Ray S, Rogers L, Pagel C, Raman S, Peters MJ, Ramnarayan P. PaO2/FIO2 Ratio Derived From the SpO2/FIO2 Ratio to Improve Mortality Prediction Using the Pediatric Index of Mortality-3 Score in Transported Intensive Care Admissions. Pediatr Crit Care Med. 2017;18(3):e131-e6. Straney L, Clements A, Parslow RC, Pearson G, Shann F, Alexander J, et al. Paediatric index of mortality 3: an updated model for predicting mortality in pediatric intensive care*. Pediatr Crit Care Med. 2013;14(7):673-81. Leteurtre S, Duhamel A, Salleron J, Grandbastien B, Lacroix J, Leclerc F. PELOD-2: an update of the PEdiatric logistic organ dysfunction score. Crit Care Med. 2013;41(7):1761-73. Pollack MM, Patel KM, Ruttimann UE. PRISM III: an updated Pediatric Risk of Mortality score. Crit Care Med. 1996;24(5):743-52. Meyer NJ, Gattinoni L, Calfee CS. Acute respiratory distress syndrome. Lancet. 2021;398(10300):622-37. 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. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. 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-5433087","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":379500757,"identity":"0b49cc1a-4c43-418e-bda4-493dc6731cd5","order_by":0,"name":"Yuetong Shen","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Yuetong","middleName":"","lastName":"Shen","suffix":""},{"id":379500758,"identity":"c01552f1-a82b-49d7-ac22-ece5ff5fe7d4","order_by":1,"name":"Wei Xu","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Wei","middleName":"","lastName":"Xu","suffix":""},{"id":379500759,"identity":"766180ea-73a1-44ba-8048-d7a547078601","order_by":2,"name":"Wenliang Song","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAABC0lEQVRIie2QMUvEMBSAUwrpEs81R+XyF54EbtHBn5JS6C09cMzYW9Kl7jf5Gzo5p2QNzooOiuCig7f1QNDcFdwuXYXLN7wXkvfx8h5CgcA/hFW7eH1JcFKJ3XGGk1p7Fdg/QzE7JXqv8Amxwq8M0fDpeijMbukV+JXkxnwQiLNWi9dNL58XiiKBenl3eJbmvrgggJ2i85TY96VKVzpq7NPhNg/lnJdAsrarRBops1RnWsSRGlVo1hqUb7fKLDAVMKbwtxKATxUq6IkyYlQBa+fxNwi3ZOSGsuZcuSV3vllY3fDNWv4QzD7zx14axuq6e+ml52MIYTpkIv6utK/eEX8NORkrDAQCgWPlF8hBXNKkSD+KAAAAAElFTkSuQmCC","orcid":"","institution":"","correspondingAuthor":true,"prefix":"","firstName":"Wenliang","middleName":"","lastName":"Song","suffix":""}],"badges":[],"createdAt":"2024-11-11 15:08:17","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-5433087/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-5433087/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":71807622,"identity":"bcc37189-2853-4a2a-b519-0c582aa1f50c","added_by":"auto","created_at":"2024-12-18 17:46:32","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":74670,"visible":true,"origin":"","legend":"\u003cp\u003eSee image above for figure legend\u003c/p\u003e","description":"","filename":"figure1.png","url":"https://assets-eu.researchsquare.com/files/rs-5433087/v1/490c8d9064b5bfb7abf564e0.png"},{"id":71807621,"identity":"3b9afe58-d0b8-4ad0-a67f-d41239a97c8b","added_by":"auto","created_at":"2024-12-18 17:46:32","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":61970,"visible":true,"origin":"","legend":"\u003cp\u003eSee image above for figure legend\u003c/p\u003e","description":"","filename":"figure2.png","url":"https://assets-eu.researchsquare.com/files/rs-5433087/v1/f1aa103dbbda7d3fe68d00b4.png"},{"id":71807623,"identity":"fbe350c7-a178-458b-90e8-1ed336b70461","added_by":"auto","created_at":"2024-12-18 17:46:32","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":217003,"visible":true,"origin":"","legend":"\u003cp\u003eLegend not included with this version\u003c/p\u003e","description":"","filename":"figure3.png","url":"https://assets-eu.researchsquare.com/files/rs-5433087/v1/59320a76de3512ca713f53be.png"},{"id":71808853,"identity":"a0ce55c9-eaf8-4d69-961d-af31e06e5a90","added_by":"auto","created_at":"2024-12-18 18:02:35","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1019549,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-5433087/v1/e98e9508-ca6d-4d17-82fb-3d43a9e71572.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Mortality Risk Factors and Clinical Profiles of Pediatric Adenovirus Pneumonia: A Study from a Comprehensive Hospital in Northeast China","fulltext":[{"header":"1 Introduction","content":"\u003cp\u003eThe 21st century has witnessed several viral epidemics that present significant public health challenges globally. In China, outbreaks of severe acute respiratory syndrome (SARS), avian influenza (H5N1), influenza A (H1N1), hand, foot, and mouth disease (EV71), and the recent COVID-19 pandemic highlighted the impact of viral diseases on healthcare systems \u003csup\u003e[\u003cspan additionalcitationids=\"CR2 CR3 CR4\" citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]\u003c/sup\u003e. Among these viruses, human adenovirus (HAdV) has emerged as a significant pathogen known for its highly contagious nature and ability to cause a broad spectrum of clinical symptoms, such as respiratory tract infections, conjunctivitis, gastroenteritis, and urinary tract infections \u003csup\u003e[\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e]\u003c/sup\u003e. Although HAdV infections are generally self-limiting, they can lead to severe adenovirus pneumonia (ADVP) in pediatric populations, which is often associated with high morbidity and mortality \u003csup\u003e[\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]\u003c/sup\u003e. Unlike other community-acquired pneumonias (CAP), such as Mycoplasma and \u003cem\u003eStaphylococcus aureus\u003c/em\u003e pneumonia, severe adenovirus pneumonia (SAP) is difficult to diagnose in its early stages because of the nonspecific clinical symptoms and the underdeveloped immune system in children, particularly their humoral immunity, which contributes to the high mortality rate \u003csup\u003e[\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]\u003c/sup\u003e. The lack of specific antiviral treatments further complicates management, often leaving supportive care as the primary intervention. Given its severity, SAP is a frequent cause of admission to pediatric intensive care units (PICUs), where the primary challenge lies in early identification and intervention to prevent fatal outcomes.\u003c/p\u003e \u003cp\u003eDespite extensive research on ADVP, a critical gap remains in the early identification of SAP risk factors at the time of PICU admission. Early identification of high-risk patients, especially within the first 24 hours of PICU admission, is crucial for initiating timely interventions that could mitigate disease progression and improve survival rates. The diverse clinical presentations complicate the timely recognition of patients at the greatest risk of mortality. Therefore, this study aims to retrospectively analyze the clinical characteristics and identify mortality risk factors in children admitted to the PICU with adenovirus pneumonia within the first 24 hours. The findings are expected to inform more effective early management strategies, optimize resource utilization, and ultimately improve patient outcomes.\u003c/p\u003e"},{"header":"2 Materials and methods","content":"\u003ch2\u003e2.1\u0026nbsp; \u0026nbsp; \u0026nbsp;Study population\u003c/h2\u003e\n\u003cp\u003eThis study is a retrospective case series analysis of 91 children who were\u0026nbsp;diagnosed with adenovirus pneumonia and admitted to the pediatric intensive care unit (PICU) of Shengjing Hospital of China Medical University (Northeast National Regional Pediatric Center) between January 1, 2018, and December 31, 2020. This is a noninterventional, retrospective case series. The study population consisted of all pediatric patients meeting the inclusion criteria during the specified timeframe. The inclusion criteria were as follows: (1) aged between 28 days and 14 years; (2) confirmed adenovirus infection through high-throughput genetic testing of DNA from respiratory samples (nasopharyngeal swabs, deep airway sputum, or alveolar lavage fluid) or detection of serum IgM antibodies by indirect immunofluorescence and met the diagnostic criteria for adenovirus pneumonia. The exclusion criteria were as follows: (1) incomplete medical records and (2) comorbidities such as neuromuscular diseases, inherited metabolic disorders, severe immunodeficiency, and myelosuppression associated with hematologic malignancies. The study was approved by the Ethics Committee of Shengjing Hospital (Approval number: 2022PS018K). Informed consent was waived because of the retrospective nature of the study. No specific sampling methods, such as randomization, were used, as all available cases were included for analysis. Data were extracted from medical records for each patient.\u003c/p\u003e\n\u003ch2\u003e2.2\u0026nbsp; \u0026nbsp; \u0026nbsp; Research definitions\u003c/h2\u003e\n\u003cp\u003eAdenovirus pneumonia was diagnosed on the basis of a combination of clinical manifestations, radiological findings, and laboratory confirmation of adenovirus infection. The diagnostic criteria for adenovirus pneumonia followed the Diagnostic and Treatment Guidelines for Adenovirus Pneumonia in Children (2019 Edition)\u003csup\u003e\u0026nbsp;[9]\u003c/sup\u003e, whereas the criteria for severe pneumonia were based on the Guidelines for the Management of Community-Acquired Pneumonia in Children (2013 Revision) \u003csup\u003e[10]\u003c/sup\u003e. Severe adenovirus pneumonia (SAP) was defined as meeting the criteria for both adenovirus pneumonia and severe pneumonia.\u003c/p\u003e\n\u003ch2\u003e2.3\u0026nbsp; \u0026nbsp; \u0026nbsp;Research data collection\u003c/h2\u003e\n\u003cp\u003eBlood samples (2\u0026ndash;5 mL) were collected from each child within 24 hours of PICU admission and immediately processed for blood gas analysis, complete blood count, biochemical tests, and assessment of inflammatory markers (e.g., CRP, PCT, and IL-6). Respiratory samples, including nasopharyngeal swabs, lower respiratory tract sputum, and alveolar lavage fluid, were collected via sterile techniques for pathogen detection via high-throughput DNA sequencing. Nasopharyngeal swabs were collected by gently inserting the swab into the nasopharynx, whereas lower respiratory tract sputum and alveolar lavage fluid were collected as needed, often via bronchoscopy. Comprehensive clinical data, including present illness, personal history (e.g., history of premature birth), past medical history (e.g., allergies, previous respiratory infections), and family history, were recorded. Detailed clinical characteristics during hospitalization, including age of onset, season of onset, presenting symptoms, peak temperature, fever duration, pulmonary signs, imaging findings, complications, and length of hospital stay, were documented.\u003c/p\u003e\n\u003ch2\u003e2.4\u0026nbsp; \u0026nbsp; \u0026nbsp;Statistical methods\u003c/h2\u003e\n\u003cp\u003eStatistical analysis was conducted via IBM SPSS software (version 22.0; Armonk, NY, United States). Normally distributed continuous variables were analyzed via independent t tests, whereas nonnormally distributed variables were assessed via the Mann\u0026ndash;Whitney U test. Categorical variables are expressed as numbers (n) and percentages (%), with continuous variables presented as medians and interquartile ranges (IQRs). Differences between groups were evaluated via the chi-square test. A multivariate analysis was performed via a stepwise logistic regression model to identify independent risk factors for mortality. A p value of less than 0.05 was considered statistically significant.\u003c/p\u003e"},{"header":"3 Results","content":"\u003cp\u003eThe epidemiological data for the 91 children diagnosed with adenovirus pneumonia are presented in Figs.\u0026nbsp;1 and 2. The patients\u0026rsquo; demographic information is summarized in Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e, and their clinical features are detailed in Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e. The laboratory results and radiological findings are provided in Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eBasic characteristics of 91 children with adenovirus pneumonia\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"5\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eTotal\u003c/p\u003e \u003cp\u003e(n\u0026thinsp;=\u0026thinsp;91) n (%)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eSurvival group (n\u0026thinsp;=\u0026thinsp;79) n (%)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eDeath group (n\u0026thinsp;=\u0026thinsp;12) n (%)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eP-value\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eGender\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eboy\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e60 (65.9)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e52 (65.8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e9 (75.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003egirl\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e31 (34.1)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e27 (24.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e3 (25.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.764\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eAge, months, median(IQR)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e2.6 (1.5\u0026thinsp;~\u0026thinsp;4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e2.8 (1.7\u0026thinsp;~\u0026thinsp;4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e1.3 (0.7\u0026thinsp;~\u0026thinsp;2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eAge distribution, years\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u0026le;\u0026thinsp;2 years old\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e37 (40.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e27 (34.2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e10 (83.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u0026gt;\u0026thinsp;2 years old\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e54 (59.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e52 (65.8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e2 (16.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e0.004\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eHistory of preterm\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e10 (11.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e6 (7.6)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e4 (33.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e0.031\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eHistory of allergy\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e33 (36.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e30 (38.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e3 (25.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.583\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eHistory of lower respiratory tract infections\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e29 (31.9)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e27 (34.2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e2 (16.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.379\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eClinical characteristics of 91 children with adenovirus pneumonia.\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"5\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eTotal\u003c/p\u003e \u003cp\u003e(n\u0026thinsp;=\u0026thinsp;91) n (%)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eSurvival group (n\u0026thinsp;=\u0026thinsp;79) n (%)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eDeath group (n\u0026thinsp;=\u0026thinsp;12) n (%)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eP-value\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003ePeak Fever, ℃, median(IQR)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e39.3 (38.5\u0026ndash;39.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e39.2 (38.5\u0026ndash;39.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e39.3 (38.9\u0026ndash;39.8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e(Z=-0.722)0.470\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eFever duration, days, median (IQR)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e7(5\u0026thinsp;~\u0026thinsp;12)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e7(5\u0026thinsp;~\u0026thinsp;10)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e16 (6.5\u0026thinsp;~\u0026thinsp;21)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e(Z=-2.391)0.083\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003ehospitalization duration, days, median (IQR)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e9(7\u0026thinsp;~\u0026thinsp;14)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e8(7\u0026thinsp;~\u0026thinsp;11)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e29 (13.5\u0026thinsp;~\u0026thinsp;34.5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e(Z=-3.558)\u003cb\u003e0.000\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eRespiratory symptoms and signs\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ecough\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e73 (80.2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e68 (86.1)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e5 (41.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eWheeze\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e16 (17.6)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e12 (15.2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e4 (33.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.258\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eRapid respiration\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e25 (27.5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e21 (26.6)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e4 (33.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.888\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ehypoxia\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e27 (29.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e23 (29.1)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e4 (33.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTriple retraction sign\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e28 (30.8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e23 (29.1)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e5 (41.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.588\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003elung auscultation\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCrackles\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e43 (47.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e39 (49.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e4 (33.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.300\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ewheezing\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e27 (29.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e21 (26.6)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e6 (50.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.188\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eExtrapulmonary manifestations on admission\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNeurological symptoms \u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e20 (22.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e14 (17.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e6 (50.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e0.032\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eGastrointestinal symptoms\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e5 (5.5%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e4 (5.1)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e1 (8.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003econjunctivitis\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e5 (5.5%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0 (0.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e5 (6.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.828\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eskin rash\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e3 (3.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e2(2.5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e1 (8.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.856\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"5\"\u003eNote: * Tachypnea: \u0026lt;1 year: \u0026gt;50 breaths/min; 1\u0026ndash;5 years: \u0026gt;40 breaths/min; \u0026ge;5 years: \u0026gt;30 breaths/min. Hypoxia: transcutaneous oxygen saturation below 92%. Neurological symptoms: depression, irritability, irritability, convulsions, blurred consciousness, coma. Gastrointestinal symptoms: diarrhea, vomiting.\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab3\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eExaminational findings of 91 children with adenovirus pneumonia\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"5\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eTotal\u003c/p\u003e \u003cp\u003e(n\u0026thinsp;=\u0026thinsp;91) n (%)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eSurvival group (n\u0026thinsp;=\u0026thinsp;79) n (%)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eDeath group (n\u0026thinsp;=\u0026thinsp;12) n (%)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eP-value\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eLaboratory indexes\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ecarbon dioxide retention\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e9 (9.9)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e5 (6.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e4 (33.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e0.045\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eP/F ratio\u0026thinsp;\u0026lt;\u0026thinsp;300 mmHg\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e33 (36.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e24 (30.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e9 (75.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e0.08\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eWBC, \u0026times;10^9/L, median (IQR)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e9.5 (6.4\u0026ndash;13.8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e9.4 (6.1\u0026ndash;12.6)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e12.6 (9.2\u0026ndash;14.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e(Z=-1.501)\u003c/p\u003e \u003cp\u003e0.133\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHGB, g/L,\u003c/p\u003e \u003cp\u003eMedian (IQR)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e115 (106\u0026thinsp;~\u0026thinsp;122)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e116 (109\u0026thinsp;~\u0026thinsp;123)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e101 (97\u0026thinsp;~\u0026thinsp;112)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e(Z=-3.163)\u003c/p\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePLT, \u0026times;10^9/L, median (IQR)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e268 (217\u0026thinsp;~\u0026thinsp;348)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e268 (218\u0026thinsp;~\u0026thinsp;322)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e269 (202\u0026thinsp;~\u0026thinsp;392)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e(Z=-0.364)\u003c/p\u003e \u003cp\u003e0.729\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCRP\u003csup\u003e**,\u003c/sup\u003e mg/L, median (IQR)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e18.6 (5-51.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e17.7 (4.5\u0026ndash;51.1)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e31.2 (11.8\u0026ndash;90)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e(Z=-1.233)\u003c/p\u003e \u003cp\u003e0.218\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePCT\u003csup\u003e**\u003c/sup\u003e, ng/mL, median (IQR)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.26 (0.1 to 0.9)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.23 (0.1 to 0.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.14 (0.4\u0026ndash;6.1)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e(Z=-2.733)\u003c/p\u003e \u003cp\u003e0.362\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eIL-6\u003csup\u003e**\u003c/sup\u003e, pg/mL, median (IQR)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e31.2 (9.6\u0026ndash;75.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e25.4 (9.6\u0026ndash;53.6)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e109.8 (44.8\u0026ndash;287)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e(Z=-2.569)\u003c/p\u003e \u003cp\u003e0.147\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ehypoalbuminemia\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e12 (13.2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e6 (7.6)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e6 (50.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e0.000\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eLDH\u0026thinsp;\u0026gt;\u0026thinsp;600U/L\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e27(29.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e20(25.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e7(58.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e0.046\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eRadiologic findings (n\u0026thinsp;=\u0026thinsp;69)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003emottled opacity\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e58 (84.1)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e47 (82.5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e11 (91.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.720\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eStreak opacity\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e12 (17.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e8 (14.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e4 (33.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.236\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003econsolidation\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e28 (40.6)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e20 (35.1)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e8 (66.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.089\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMulti-lobe consolidation (\u0026ge;\u0026thinsp;3 lobes)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e23 (33.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e16 (28.1)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e7 (58.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.92\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003epleural effusion\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e10 (14.5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e4 (7.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e6 (50.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e0.01\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"5\"\u003eNote : * Carbon dioxide retention: carbon dioxide partial pressure\u0026thinsp;\u0026gt;\u0026thinsp;50 mmHg; P/F ratio: PaO2/FiO2; WBC: white blood cells; HGB: Hemoglobin; PLT: Platelet; CRP: C-reactive protein; PCT: procalcitonin;IL6: interleukin 6; hypoalbuminemia: albumin\u0026thinsp;\u0026lt;\u0026thinsp;30 g/L; LDH: Lactate dehydrogenase;\u003c/td\u003e\u003c/tr\u003e \u003ctr\u003e\u003ctd colspan=\"5\"\u003eNormal value range of laboratory indexes in our hospital: CRP: 0\u0026thinsp;~\u0026thinsp;8mg/L, PCT: \u0026lt;0.05ng/mL, IL6: \u0026le;7pg/mL, LDH: 125\u0026ndash;243;\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eAmong the 91 children diagnosed with adenovirus pneumonia, 79 recovered, and 12 died, resulting in a case fatality rate of 13.19%. The main causes of death in the 12 patients were severe dyspnea (100%), ARDS (58.3%) and sepsis (41.7%). Adenovirus pneumonia was more prevalent during autumn (34.1%) and winter (38.5%), with the mortality rate peaking at 22.9% in winter (Fig.\u0026nbsp;1). Between 2018 and 2020, mortality rates significantly declined after reaching a peak of 35.2% in 2018 (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05). Similarly, morbidity rates peaked in 2019 but decreased sharply the following year, with only four cases reported in January 2020 (Fig.\u0026nbsp;2).\u003c/p\u003e \u003cp\u003eAs shown in Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e, the incidence of adenovirus pneumonia was greater in males (65.9%), with a median age of onset of 2.6 years. Approximately one-third of the children had a history of allergies and lower respiratory tract infections. Statistically, children born prematurely and those aged\u0026thinsp;\u0026le;\u0026thinsp;2 years were more likely to succumb to the illness (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05).\u003c/p\u003e \u003cp\u003eTable\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e highlights that all the children experienced fever upon admission, with a median peak temperature of 39.3\u0026deg;C (IQR: 38.5\u0026ndash;39.7\u0026deg;C), and fever lasted for a median duration of 7 days (IQR: 5\u0026ndash;12 days). In the group that died, the fever duration was notably longer, with a median duration of 16 days (IQR: 6.5\u0026ndash;21 days). Hospitalization durations were significantly longer in the nonsurviving group, with a median of nearly one month. Cough was the most common respiratory symptom, observed in 73 children (80.2%), but its absence at admission was associated with a significantly greater likelihood of death (P\u0026thinsp;=\u0026thinsp;0.001). Severe respiratory symptoms such as hypoxia (29.7%), rapid respiration (27.5%) and a positive triple concave sign (30.8%) were observed in both groups, but there were no statistically significant differences between the survival and death groups. Posthospitalization lung auscultation revealed crackles in 47.3% of the children and wheezing in 29.7%. Neurological symptoms were present in 20 children (22.0%), and these symptoms were significantly more common in the group that died (50.0% vs. 17.7%, P\u0026thinsp;=\u0026thinsp;0.032). Gastrointestinal symptoms (such as vomiting and diarrhea) and skin manifestations (e.g., rash and conjunctivitis) were less common and were not significantly different between the groups.\u003c/p\u003e \u003cp\u003eTable\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e indicates that, unlike those with bacterial pneumonia, children with adenoviral pneumonia did not exhibit significant increases in infection indicators (leukocytes, CRP, PCT, and IL-6) upon hospital admission. There were no statistically significant differences in hemoglobin or platelet levels between the survival and nonsurviving groups. Children with carbon dioxide retention (P\u0026thinsp;=\u0026thinsp;0.045), hypoalbuminemia (P\u0026thinsp;=\u0026thinsp;0.000), and elevated lactate dehydrogenase (LDH\u0026thinsp;\u0026gt;\u0026thinsp;600 U/L) (P\u0026thinsp;=\u0026thinsp;0.046) had significantly higher mortality rates. Radiological findings revealed that mottled opacity was the most common observation (84.1%), followed by consolidation (40.6%). Multilobe consolidation (involvement of \u0026ge;\u0026thinsp;3 lobes) was present in 33.3% of the patients, and pleural effusion was significantly more common in the group that died (50.0% vs. 7.0%, P\u0026thinsp;=\u0026thinsp;0.01).\u003c/p\u003e \u003cp\u003eMultivariate analysis, which incorporates statistically significant variables from the univariate analysis into a logistic regression model, identified age\u0026thinsp;\u0026le;\u0026thinsp;2 years (OR: 24.542, 95% CI: 1.443\u0026thinsp;~\u0026thinsp;417.42), preterm birth (OR: 36.107, 95% CI: 1.444\u0026thinsp;~\u0026thinsp;903.032), and a P/F ratio\u0026thinsp;\u0026lt;\u0026thinsp;300 mmHg (OR: 19.725, 95% CI: 1.539\u0026thinsp;~\u0026thinsp;252.808) as independent risk factors for mortality in children with adenovirus pneumonia (see Table\u0026nbsp;\u003cspan refid=\"Tab4\" class=\"InternalRef\"\u003e4\u003c/span\u003e and Fig.\u0026nbsp;3 for details).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab4\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 4\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eLogistic regression analysis of mortality risk factors for children with adenovirus pneumonia\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"7\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eB\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eS.E\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eWals\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eP\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003eOR\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\"\u003e \u003cp\u003e95% CI\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAge\u0026thinsp;\u0026le;\u0026thinsp;2 years\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e3.200\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e1.446\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e4.900\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e0.027\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e24.542\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e1.443\u0026thinsp;~\u0026thinsp;417.423\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003epreterm\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e3.586\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e1.643\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e4.768\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e0.029\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e36.107\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e1.444\u0026thinsp;~\u0026thinsp;903.032\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNeurological symptoms\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e2.385\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e1.331\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e3.210\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.073\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e10.854\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e0.799\u0026thinsp;~\u0026thinsp;147.373\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eP/F ratio\u0026thinsp;\u0026lt;\u0026thinsp;300 mmHg\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e2.982\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e1.301\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e5.250\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e0.022\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e19.725\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e1.539\u0026thinsp;~\u0026thinsp;252.808\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ecarbon dioxide retention\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e3.041\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e1.953\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e2.426\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.119\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e20.936\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e0.456\u0026thinsp;~\u0026thinsp;961.940\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ehypoalbuminemia\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e.856\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e1.177\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e.530\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.467\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e2.354\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e0.235\u0026thinsp;~\u0026thinsp;23.625\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eLDH\u0026thinsp;\u0026gt;\u0026thinsp;600U/L\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e2.578\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e1.688\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e2.334\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.127\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e13.175\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e0.482\u0026thinsp;~\u0026thinsp;359.900\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e"},{"header":"4 Discussion","content":"\u003cp\u003eThe findings of this study highlight several key epidemiological and clinical characteristics associated with adenovirus pneumonia (ADVP) in Northeast China. Notably, adenovirus pneumonia (ADVP) in our study was most prevalent in winter in Northeast China, with the highest mortality rates observed during this season, suggesting that healthcare providers should be particularly vigilant during the winter months. This finding contrasts with reports from southern China, where ADVP incidence peaks in spring and summer \u003csup\u003e[\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]\u003c/sup\u003e, and differs from patterns observed in other countries \u003csup\u003e[\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e]\u003c/sup\u003e. This phenomenon is likely related to the circulation of various adenovirus subtypes in different regions, as different subtypes can exhibit distinct epidemiological traits, including transmissibility and virulence \u003csup\u003e[\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]\u003c/sup\u003e. SAP syndrome and acute respiratory distress syndrome are typically associated with HAdV types 3, 7, 14, 21, and 55, which are more prevalent among immunocompromised individuals, particularly infants and young children aged 6 to 24 months \u003csup\u003e[\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]\u003c/sup\u003e. Unfortunately, our study did not include adenovirus subtype identification. The overall PICU mortality rate for adenovirus pneumonia patients was 13.19%. This rate may be high, as data from children treated in general wards with less severe adenovirus infections were not included.\u003c/p\u003e \u003cp\u003eNotably, our study revealed a sharp decline in PICU admissions for adenovirus pneumonia in 2020. This trend coincides with the onset of the coronavirus disease 2019 (COVID-19) pandemic, which originated in Wuhan, China, in December 2019 and led to significant changes in public behavior. Several studies \u003csup\u003e[\u003cspan additionalcitationids=\"CR15\" citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e]\u003c/sup\u003e have demonstrated that strict respiratory protection measures and restrictions on crowd activities significantly impact the transmission dynamics of adenovirus. Although our study's sample size is limited, our findings align with these conclusions.\u003c/p\u003e \u003cp\u003eAdditionally, evidence \u003csup\u003e[\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e]\u003c/sup\u003e suggests that as COVID-19 restrictions are relaxed, the prevalence of non-SARS-CoV-2 respiratory viruses, including adenovirus, may increase. Given that adenovirus pneumonia outbreaks have been reported in various regions of China, including Beijing, Chongqing, Guangzhou, and Taiwan, from 2011\u0026ndash;2018 \u003csup\u003e[\u003cspan additionalcitationids=\"CR19 CR20\" citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e]\u003c/sup\u003e, vigilance against the potential resurgence of adenovirus infections in Shenyang is needed. Therefore, we should increase education on respiratory protection for children, especially during the winter season.\u003c/p\u003e \u003cp\u003eOne of the most critical findings from this study is the identification of specific risk factors for mortality in children with ADVP. The multivariate analysis revealed that age\u0026thinsp;\u0026le;\u0026thinsp;2 years, preterm birth, and a P/F ratio\u0026thinsp;\u0026lt;\u0026thinsp;300 mmHg were independent predictors of mortality. Our results align with those of previous studies that identified age\u0026thinsp;\u0026le;\u0026thinsp;2 years as a significant risk factor for SAP and associated mortality \u003csup\u003e[\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e, \u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e, \u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e]\u003c/sup\u003e. Our findings further suggest that even premature infants older than 28 days are at elevated risk of death due to adenovirus pneumonia. Pediatric airways differ markedly from those of adults, particularly in the first two years of life \u003csup\u003e[\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e]\u003c/sup\u003e. Infants with narrower, more pliable airways are more susceptible to increased airflow resistance during adenovirus infections. Inflammation and secretions can easily obstruct these airways, but their immature alveolar and bronchial systems lack effective collateral ventilation, leading to compromised gas exchange in parts of the lung and resulting in severe respiratory distress \u003csup\u003e[\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e]\u003c/sup\u003e. Additionally, infants' limited respiratory reserve and underdeveloped, fatigue-prone respiratory muscles, especially in preterm infants, further increase the risk of respiratory muscle fatigue, which can result in severe respiratory distress and potentially death \u003csup\u003e[\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e]\u003c/sup\u003e. Furthermore, our findings indicate that even premature infants older than 28 days face an elevated risk of death due to adenovirus pneumonia. Pediatric airways differ significantly from those of adults, particularly during the first two years of life \u003csup\u003e[\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e]\u003c/sup\u003e. In immunocompromised individuals, dissemination of the virus and/or severe respiratory failure can develop in 10 to 30% of ADVP cases \u003csup\u003e[\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]\u003c/sup\u003e.\u003c/p\u003e \u003cp\u003eOur study revealed that mottled opacity (84.1%) and consolidation (40.6%) are common in patients with adenovirus pneumonia. The incidence of pleural effusion significantly differed between the survival and death groups (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05), indicating that in children with adenovirus pneumonia, infection often leads to extensive lung inflammation, resulting in alveolar filling with fluid, debris, and inflammatory cells. This process significantly impairs gas exchange, reducing the effective surface area available for oxygen transfer from the alveoli to the bloodstream. The PaO2/FiO2 (P/F) ratio has traditionally served as an indicator of lung injury and can be used to quantify the gas exchange capacity at the alveolar surface \u003csup\u003e[\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e]\u003c/sup\u003e. It is a variable included in most pediatric severity of illness scores \u003csup\u003e[\u003cspan additionalcitationids=\"CR28\" citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e]\u003c/sup\u003e. A P/F ratio\u0026thinsp;\u0026lt;\u0026thinsp;300 mmHg indicates severe impairment of oxygen exchange. Our study highlights that the P/F ratio at admission strongly correlates with mortality. This finding is significant because a low P/F ratio serves not only as a marker of disease severity but also as an important prognostic factor for identifying children at high risk of mortality.\u003c/p\u003e \u003cp\u003eMoreover, the persistence of a low P/F ratio despite oxygen therapy suggests refractory hypoxemia, a condition that often necessitates advanced interventions such as mechanical ventilation or extracorporeal membrane oxygenation (ECMO). The concept that ventilators can both rescue and harm children is not new. Research has shown that invasive mechanical ventilation is an independent risk factor for death in SAP patients \u003csup\u003e[\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e]\u003c/sup\u003e. This phenomenon is related not only to alveolar epithelial injury induced by adenovirus but also to hyperoxia or mechanical stretching by the ventilator \u003csup\u003e[\u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e]\u003c/sup\u003e.\u003c/p\u003e \u003cp\u003eThe clinical implications of these findings are significant, particularly for the management of high-risk pediatric patients with adenovirus pneumonia. Identifying young age, prematurity, and a low P/F ratio as key risk factors for mortality underscores the need for heightened surveillance and early, aggressive intervention in these populations. Clinicians should be particularly vigilant in monitoring respiratory function in young children and preterm infants with ADVP, as early signs of hypoxemia may necessitate prompt escalation of care, including consideration of advanced respiratory support techniques.\u003c/p\u003e \u003cp\u003e This study provides valuable insights into the clinical characteristics and mortality risk factors for adenovirus pneumonia (ADVP) in Northeast China, a region where epidemiological data on ADVP are relatively scarce compared with those from southern China, which are more extensively studied. Despite these contributions, our study has certain limitations that must be acknowledged. The most significant limitation is the relatively small sample size, which may limit the generalizability of our findings. Additionally, the inability to subtype the adenovirus strains in this study restricted our ability to analyze the specific epidemiological and clinical variations attributable to different adenovirus subtypes. Furthermore, as a comprehensive hospital, patients older than 14 years are transferred to adult wards for treatment. As a result, we do not have data for children aged 14 to 18 years, which limits the scope of our findings to younger pediatric populations. This age-related data gap may lead to the overlooking of important clinical characteristics and risk factors that are relevant to older adolescents with adenovirus pneumonia.\u003c/p\u003e \u003cp\u003eGiven these limitations, future research should aim to include larger, multicenter cohorts to validate and expand upon our findings. Furthermore, incorporating molecular diagnostic techniques to identify specific adenovirus subtypes could provide a more detailed understanding of the epidemiological patterns and clinical outcomes associated with different strains. These studies are crucial for developing targeted interventions and improving the management of adenovirus pneumonia in pediatric populations across various geographic regions.\u003c/p\u003e \u003cp\u003eMoreover, investigating the influence of early intervention strategies on outcomes in children with low P/F ratios could provide critical insights into how best to manage high-risk patients. These strategies could include the use of noninvasive ventilation, early initiation of corticosteroids or antiviral therapies, and supportive care measures such as fluid management and nutritional support. Understanding the timing and effectiveness of these interventions could lead to improved protocols and better survival rates for children with adenovirus pneumonia.\u003c/p\u003e \u003cp\u003eFurther studies should also investigate the long-term outcomes of children who survive adenovirus pneumonia, particularly those who require mechanical ventilation or other advanced respiratory support. Understanding the potential for long-term respiratory or neurological sequelae could inform follow-up care and rehabilitation strategies for these patients.\u003c/p\u003e \u003cp\u003eGiven the impact of public health measures on viral transmission, future studies could also explore the interplay between these measures and the incidence of adenovirus infections, providing insights into how best to prevent future outbreaks.\u003c/p\u003e"},{"header":"5 Conclusion","content":"\u003cp\u003eThis study revealed that age\u0026thinsp;\u0026le;\u0026thinsp;2 years, a history of preterm birth, and a low PaO2/FiO2 (P/F) ratio at admission are significant independent risk factors for mortality in patients with adenovirus pneumonia. These findings underscore the critical importance of early recognition and prompt intervention in these high-risk pediatric populations. Given the high mortality rates associated with these risk factors, healthcare providers should prioritize the early identification of these vulnerable groups upon their admission to the Pediatric Intensive Care Unit (PICU). Additionally, the research underscores the need for heightened vigilance during the winter months when adenovirus pneumonia incidence and mortality rates peak. Despite limitations such as a relatively small sample size and the lack of data for adolescents aged 14 to 18 years, this study contributes valuable insights into the epidemiology and management of severe adenovirus pneumonia in children, particularly in Northeast China.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003eEthics approval and consent to participate\u003c/p\u003e\n\u003cp\u003eThe study was approved by the Ethics Committee of Shengjing Hospital (Approval number: 2022PS018K). Informed consent was waived because of the retrospective nature of the study.\u003c/p\u003e\n\u003cp\u003eConsent for publication\u003c/p\u003e\n\u003cp\u003eNot applicable\u003c/p\u003e\n\u003cp\u003eAvailability of data and materials\u003c/p\u003e\n\u003cp\u003eThe datasets analysed during the current study are available from the corresponding author on reasonable request\u003c/p\u003e\n\u003cp\u003eCompeting interests\u003c/p\u003e\n\u003cp\u003eThe authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as potential conflicts of interest\u003c/p\u003e\n\u003cp\u003eFunding\u003c/p\u003e\n\u003cp\u003eThe authors received no financial support for the research, authorship, or publication of this article\u003c/p\u003e\n\u003cp\u003eAuthors\u0026apos; contributions\u003c/p\u003e\n\u003cp\u003eY.S. designed the study, collected the data and drafted the manuscript. W.S. and W.X. supervised the study and revised the manuscript critically for important intellectual content. All the authors read and approved the final manuscript.\u003c/p\u003e\u003cp\u003eAuthorship\u003c/p\u003e\n\u003cp\u003eY.S. designed the study, collected the data and drafted the manuscript. W.S. and W.X. supervised the study and revised the manuscript critically for important intellectual content. All the authors read and approved the final manuscript.\u003c/p\u003e\n\u003cp\u003eConflict of interest\u003c/p\u003e\n\u003cp\u003eThe authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as potential conflicts of interest.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eZhong NS, Zheng BJ, Li YM, Poon, Xie ZH, Chan KH, et al. Epidemiology and cause of severe acute respiratory syndrome (SARS) in Guangdong, People\u0026apos;s Republic of China, in February, 2003. 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Pediatr Infect Dis J. 2011;30(11):948-52. \u003c/li\u003e\n\u003cli\u003eDi Cicco M, Kantar A, Masini B, Nuzzi G, Ragazzo V, Peroni D. Structural and functional development in airways throughout childhood: Children are not small adults. Pediatr Pulmonol. 2021;56(1):240-51. \u003c/li\u003e\n\u003cli\u003eWang X, Tan X, Li Q. The difference in clinical features and prognosis of severe adenoviral pneumonia in children of different ages. J Med Virol. 2022;94(7):3303-11. \u003c/li\u003e\n\u003cli\u003eRay S, Rogers L, Pagel C, Raman S, Peters MJ, Ramnarayan P. PaO2/FIO2 Ratio Derived From the SpO2/FIO2 Ratio to Improve Mortality Prediction Using the Pediatric Index of Mortality-3 Score in Transported Intensive Care Admissions. Pediatr Crit Care Med. 2017;18(3):e131-e6. \u003c/li\u003e\n\u003cli\u003eStraney L, Clements A, Parslow RC, Pearson G, Shann F, Alexander J, et al. Paediatric index of mortality 3: an updated model for predicting mortality in pediatric intensive care*. Pediatr Crit Care Med. 2013;14(7):673-81. \u003c/li\u003e\n\u003cli\u003eLeteurtre S, Duhamel A, Salleron J, Grandbastien B, Lacroix J, Leclerc F. PELOD-2: an update of the PEdiatric logistic organ dysfunction score. Crit Care Med. 2013;41(7):1761-73. \u003c/li\u003e\n\u003cli\u003ePollack MM, Patel KM, Ruttimann UE. PRISM III: an updated Pediatric Risk of Mortality score. Crit Care Med. 1996;24(5):743-52. \u003c/li\u003e\n\u003cli\u003eMeyer NJ, Gattinoni L, Calfee CS. Acute respiratory distress syndrome. Lancet. 2021;398(10300):622-37. \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":"Adenovirus pneumonia, Pediatric, Mortality, Risk factors, PaO2/FiO2 ratio, Preterm birth","lastPublishedDoi":"10.21203/rs.3.rs-5433087/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-5433087/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eAdenovirus pneumonia (ADVP) is a significant cause of morbidity and mortality in children admitted to the Pediatric Intensive Care Unit (PICU). This study analyzes the clinical characteristics and key risk factors for mortality in children with ADVP admitted to a PICU in Northeast China. A total of 91 cases were reviewed, with a focus on clinical features, laboratory results, and radiological findings. In Northeast China, the incidence of ADVP peaked in autumn (34.1%) and winter (38.5%), with a PICU mortality rate of 22.9% in winter. The median onset age was 2.6 years, and the overall PICU mortality rate was 13.19%. Mortality was notably higher among children aged\u0026thinsp;\u0026le;\u0026thinsp;2 years and those with a history of preterm birth. Clinical markers such as carbon dioxide retention, a low P/F ratio, hypoalbuminemia, elevated LDH levels, and pleural effusion were associated with increased mortality. Logistic regression identified age\u0026thinsp;\u0026le;\u0026thinsp;2 years (OR: 24.542, 95% CI: 1.443\u0026thinsp;~\u0026thinsp;417.42), preterm birth (OR: 36.107, 95% CI: 1.444\u0026thinsp;~\u0026thinsp;903.032), and a P/F ratio\u0026thinsp;\u0026lt;\u0026thinsp;300 mmHg (OR: 19.725, 95% CI: 1.539\u0026thinsp;~\u0026thinsp;252.808) as independent risk factors for mortality. These findings highlight the need for early risk identification and targeted interventions in high-risk pediatric groups to improve outcomes.\u003c/p\u003e","manuscriptTitle":"Mortality Risk Factors and Clinical Profiles of Pediatric Adenovirus Pneumonia: A Study from a Comprehensive Hospital in Northeast China","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-12-18 17:46:27","doi":"10.21203/rs.3.rs-5433087/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":"4c888069-c60d-45ab-bb71-143835f28e64","owner":[],"postedDate":"December 18th, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2024-12-18T17:46:30+00:00","versionOfRecord":[],"versionCreatedAt":"2024-12-18 17:46:27","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-5433087","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-5433087","identity":"rs-5433087","version":["v1"]},"buildId":"qtupq5eGEP_6zYnWcrvyt","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}