OBJECTIVETo investigate the bacterial pathogenic characteristics of respiratory tract infection in children.

METHODSThe medical data from 14,994 children with respiratory tract infection who were hospitalized in Children's Hospital Affiliated to Soochow University between November 2005 and October 2014 were retrospectively reviewed.

RESULTSAmong the 14,994 sputum samples from the children with respiratory tract infection, 3,947 (26.32%) had a positive bacterial culture. The most common bacterial pathogen was Streptococcus pneumonia (12.79%), followed by Haemophilus influenzae (5.02%) and Moraxella catarrhalis (2.91%). The bacterial detection rates differed significantly in different years and seasons and children of different ages (P<0.01). The children who had not taken antibacterial agents before admission had a significantly higher positive bacterial culture rate than those who had taken antibacterial agents (P<0.01). There were significant differences in the bacterial detection rate among the children with different course of disease (<1 month, 1-3 months and >3 months) (P<0.05). The detection rates of Streptococcus pneumonia, Moraxella catarrhalis and Acinetobacter baumannii showed an increased trend with a prolonged disease course (P<0.05).

CONCLUSIONSStreptococcus pneumonia is the most common bacterial pathogen causing respiratory tract infection in children, followed by Haemophilus influenzae and Moraxella catarrhalis. The detection rate of bacterial pathogens varies in different years and seasons and children of different ages. The course of the disease and application of antibacterial agents outside hospital can affect the detection rate of bacterial pathogens in children with respiratory tract infection.