Risk Factors for Severe Community-aquired Pneumonia Among Children Hospitalized With CAP Younger Than 5 Years of Age

Background: Community-acquired pneumonia (CAP) causes great morbidity and mortality as well as enormous economic burden worldwide. This study intended to describe the clinical characteristics of CAP and explore the risk factors of severe CAP among children in downtown Suzhou, China. Methods: This was a retrospective study of childhood hospitalizations in Soochow University Affiliated Children’s Hospital from January 1, 2010, to December 31, 2014. Children who were residents of downtown Suzhou, 29 days to < 5 years of age, with discharge diagnosis codes J09 to J18 and J20 to J22 were included. Medical charts and chest radiograph reports were reviewed for included children to collect clinical information. CAP with intensive care unit (ICU) admission and poor clinical outcome were categorized as severe CAP. Results: A total of 28,043 children were identified with CAP; 17,501 (62.4%) of these children were male, and 20,747 (74.0%) children were less than 2 years of age. The common clinical symptoms at admission were cough (94.8%), fever (52.9%), wheezing (37.7%) and respiratory distress (9.5%). In total, 21,898 (78.1%) children had radiologic evidence of pneumonia, and 1,403 (5.0%) children developed at least 1 complication. Multivariate regression analysis showed that younger age, congenital heart disease and abnormal white blood cells, and C-reactive protein results were independent risk factors for both ICU admission and poor clinical outcome (odds ratio [OR] > 1 for all). Respiratory distress symptoms at admission (OR = 12.10) greatly increased the risk for ICU admission, while ICU admission (OR = 8.87) and complications (OR = 2.55) increased the risk of poor outcome. However, cough was a protective factor for ICU admission, so were wheezing, antibiotic and antiviral therapies for clinical failure. Conclusion: Pediatric CAP hospitalizations of those of younger age, with congenital heart diseases, respiratory distress symptoms/tachypnea, abnormal white blood cells and C-reactive protein results as well as complications were at higher risk for progressing to severe CAP.