Abstract: Objective  To investigate the clinical characteristics, bacterial spectrum, drug resistance rate and outcome of peritoneal dialysis-associated peritonitis (PDAP) by multiple drug resistant organisms (MDRO), so as to provide clinical evidences for standardizing therapy of PDAP by MDRO.  Methods  Clinical data of PDAP patients admitted to The Third Hospital of Hebei Medical University during January, 2016 and December, 2022 were retrospectively reviewed. They were divided into two groups based on the results of bacterial culture in effluent dialysate, PDAP by MDRO group and PDAP not by MDRO group. Clinical data and treatment results were compared between the two groups.  Results  ①In the 96 PDAP patients, a total of 123 PDAP episodes occurred, of which 56 episodes were PDAP by MDRO. The MDRO were dominated by Gram positive bacteria (49/56, 87.5%), in which the most strains were coagulase-negative staphylococci (41/49, 83.7%); all Gram negative bacteria were Escherichia coli (E. coli). ②The average time for significant improvement of PDAP was longer in PDAP by MDRO group than in PDAP not by MDRO group (Z=-1.994 and -2.341; P=0.046 and 0.019); the average time for significant improvement of PDAP caused by Gram positive bacteria was 2.491 days longer in PDAP by MDRO group than in PDAP not by MDRO group (t=-2.254, P=0.028). ③The sensitivity of Gram positive bacteria to rifampicin increased in 2020～2022 compared to that in 2016-2019 (χ2=4.416, P=0.042).  ④In the PDAP caused by Gram positive bacteria, the recurrence rate of PDAP was higher in PDAP by MDRO group than in PDAP not by MDRO group (P=0.020).  Conclusion  The main pathogens in PDAP by MDRO group were coagulase-negative staphylococci. In PDAP patients by MDRO, the recurrence rate of PDAP was higher, the presence of PDAP symptoms was longer, and effective antibiotic therapy should be used earlier and longer.

Key words: Peritoneal dialysis, Peritoneal dialysis-associated peritonitis, Multiple drug resistant organism, Prognosis