Analysis of pathogen distribution and risk factors for extended antibiotic course in children with microbiological-based protracted bacterial bronchitis in southwest China

Background Prior studies of protracted bacterial bronchitis (PBB) in children were mainly conducted in high-income areas, and no data from low- and middle-income countries have been published. In this study, we aimed to clarify the outcomes of PBB in a larger cohort in southwest China, focusing on the pathogen distribution and risk factors with an extended course of antibiotics. Methods Children with PBB who underwent flexible bronchoscopy were included. Clinical review, cytologic examination, and semiquantitative bacterial culture of bronchoalveolar lavage fluid (BALF) were performed as clinically indicated. Multiple linear regression and decision tree analyses were used to determine factors with an extended course of antibiotics. Results The study included 138 children. Two pathogens were detected in 23 BALF samples. Streptococcus pneumoniae (Sp) and Haemophilus influenzae (Hi) were cultured in 67 and 59 BALF samples, respectively. Sp infection in BALF was an independent factor influencing the duration of the course of antibiotics ( β = 11.988, t = 2.529, P = 0.013) according to multiple linear regression. One rule was used to predict an extended course of antibiotics (>4 weeks) with accuracy of 87.54% by decision tree analysis, namely, Sp infection in BALF, percentage of neutrophils in BALF >91%, and use of inhaled corticosteroids (ICS) before admission. Conclusion The most prevalent pathogen in children with PBB in southwest China was S. pneumoniae , which necessitated a longer course of antibiotics, particularly when paired with a percentage of neutrophils in BALF >91% and administration of ICS prior to admission. Further research of children with PBB in low- and middle-income countries is urgently required.