Abstract: Background：Chinese Infectious Disease Surveillance of Pediatrics (ISPED) program collected and summarized the data of antibiotics resistance from 12 member hospitals every year to monitor the bacterial drug resistance and pathogen changes among Chinese children. Objective：To investigate the antimicrobial resistance profiles of pathogens and bacteria infection in Chinese children and guide the reasonable use of antibiotics. Design：A cross-sectional survey. MethodsFrom January 1st to December 31rd in 2022, clinical isolates were collected from children hospitals in China enrolled in ISPED program. Antimicrobial susceptibility testing was carried out according to a unified protocol using Kirby-Bauer method or automated systems. Penicillin susceptibility of streptococcus pneumonia was detected by E-test. All of the antimicrobial susceptibility testing results were interpreted according to the criteria set by Clinical and Laboratory Standards Institute (CLSI) in 2022. Main outcome measures：Distribution of bacteria strains in children, changes of bacteria drug resistance to isolated strains, and detection of multi-drug resistant organisms (MDROs). Results：A total of 50,399 isolates were collected, of which 38.8% was gram-positive organisms and 61.2% was gram-negative organisms. Top ten pathogens were as follows, Escherichia coli (14.3%), Haemophilus influenza (11.8%), Straphylococcus aureus (11.4%), Streptococcus pneumonia (11.3%), Moraxella catarrhalis (7.3%), Coagulase-negative staphylococci (6.8%), Klebsiella pneunoniae (5.3%), Pseudomonas aeruginosa (4.4%), Acinetobacter baumannii(2.3%) and Enterococcus faecalis (2.1%). E. coli was the most common pathogen in neonates and children over 5 years old. H. influenza was the major pathogen in children from the age of >28 days to 1 year. S. pneumoniae was the main pathogenic bacteria in children at the age of 1 to 5 years old. The proportion of penicillin-insensitive S. pneumoniae (PNSP) from cerebrospinal fluid and non-cerebrospinal fluid were 88.9% and 6.6%, respectively. The ratios of methicillin-resistant S. aureus (MRSA), carbapenem-resistant Enterobacteriaceae (CRE), carbapenem-resistant P. aeruginosa (CR-PA), carbapenem-resistant A. baumannii (CR-AB) were 32.8%, 4.5%, 7.6% and 24.3%, respectively. The detection rates of MRSA, CRE and CR-PA in the neonatal group were 33.2%, 6.4% and 11.3%, much higher than those in the non-neonatal group (32.6%、4.2% and 7.5%). CR-AB in the neonatal group accounted for 10.9%, which was lower than that in the non-neonatal group (26.3%). Conclusions：The detection rate of MDROs in 2022 shows the continuous decrease compared to the previous years. More attention should be paid to the colonization, infection and spread of MRSA, CRE and CR-PA in the neonatal population.

Key words: Bacteria, Antimicrobial resistance, Children, Infectious Disease Surveillance for Pediatrics, 2022