Abstract:ObjectiveTo investigate the bacterial spectrum and antimicrobial resistance of peritoneal dialysis (PD)related peritonitis, and provide evidence for rational antimicrobial use. MethodsClinical data of 120 patients with PDrelated peritonitis in a hospital from January 2013 to December 2014 were retrospectively analyzed. Results91 cases (75.83%) showed positive result in bacterial culture, 93 pathogenic strains were cultured, including 73 (78.49%) grampositive and 13 (13.98%) gramnegative bacterial strains, the most common grampositive bacteria was Staphylococcus epidermidis (n=38, 40.86%), and the main gramnegative bacteria was Escherichia coli (n=3, 3.23%). Grampositive strains had high resistance rates to penicillin, erythromycin, and oxacillin (93.65%, 69.57%, and 64.41% respectively), while resistance rates to vancomycin and linezolid were both low (2.90% and 1.47% respectively), and were sensitive to teicoplanin, tigecycline, and nitrofurantoin. Gramnegative bacteria had high resistance rates to cefazolin, cefuroxime, and ampicillin(50.00%, 37.50%, and 37.50% respectively), but were sensitive to imipenem, tobramycin, and piperacillin. Resistance rates of grampositive and gramnegative bacteria to gentamicin and levofloxacin were both low. Nonstandard operation during dialysate exchange was the most common cause of peritonitis (56.67%), most peritonitis were grampositive bacterial infection(79.41%);while gramnegative bacteria were the main pathogens of diarrheainduced peritonitis (52.63%). The cure rates of grampositive bacteria, gramnegative bacteria,and negativecultured peritonitis were 92.96%, 76.92%, and 86.21% respectively, difference was not statistically significant(χ2=3.39,P=0.18). ConclusionGrampositive bacteria are major pathogens in PDrelated peritonitis, and are usually caused by the bacteria through dialysis catheter due to nonstandard operation during dialysate exchange. Firstgeneration cephalosporins are not recommended as empirical therapy against grampositive bacteria, while vancomycin is still the best choice. Thirdgeneration cephalosporins and aminoglycosides are recommended as empirical therapy against gramnegative bacteria. Gentamicin and levofloxacin can be used alone as empirical therapy in special circumstances.