Abstract:Objective To understand the distribution characteristics and antimicrobial resistance of pathogenic bacteria from peritoneal effusion specimens in China, and provide evidence for clinical rational selection of antimicrobial agents. Methods All the surveilled data were from strains isolated from peritoneal effusion specimens reported by member hospitals of China Antimicrobial Resistance Surveillance System (CARSS) from January 2014 to September 2019, the first strain of the identical bacteria from the same patient was adopted to be analyzed finally, and repetitive strains were excluded. Results A total of 244 744 strains of non-repetitive bacteria from peritoneal effusion were isolated in 2014-2019, and the number of isolated strains showed an upward trend each year. The top 4 isolated strains were Escherichia coli (32.2%), Klebsiella pneumoniae (9.2%), Enterococcus faecium (7.3%) and Staphylococcus epidermidis (5.8%). Enterobacteriales had higher resistance rates to ceftazidime, cefotaxime and levofloxacin, and lower resistance rates to imipenem and amikacin, but Klebsiella pneumoniae had higher resistance rates to imipenem and amikacin than other Enterobacteriales. Among non-fermentative bacteria, Pseudomonas aeruginosa had low resistance to amikacin (2.3%-5.2%), Acinetobacter baumannii had high resistance to cephalosporins, carbapenems and quinolones (most were >50%), resistance rates to minocycline were 14.4%-28.4%. Isolation rate of methicillin-resistant Staphylococcus aureus (MRSA) decreased year by year, linezolid vancomycin and teicoplanin resistant strain was not found. Resistance rates of MRSA to all antimicrobial agents were all higher than those of methicillin-susceptible Staphylococcus aureus (MSSA). Enterococcus faecalis and Enterococcus faecium were the most common Enterococcus species. Except linezolid and minocycline, the overall resistances rates of Enterococcus faecalis to other antimicrobial agents were all lower than that of Enterococcus faecium. Conclusion Bacteria from peritoneal effusion are widely distributed in China, mainly Gram-negative bacilli such as Escherichia coli and Klebsiella pneumoniae, isolation rate is increasing year by year; antimicrobial resistance strains is common, the growth trend of bacterial resistance in recent 6 years is relatively stable, resistance rate of individual strains to specific antimicrobial agents present a downward trend year by year. Surveillance on some strains such as Escherichia coli, Klebsiella pneumoniae and Acinetobacter baumannii still need to be strengthened. Rational selection of antimicrobial agents should be based on antimicrobial susceptibility testing results.