Clinical Features Of Peritoneal Dialysis-associated Peritonitis And Risk Factors For Poor Clinical Prognosis

Objective:To analyze the clinical characteristics of peritoneal dialysis-associated peritonitis（PDAP）in peritoneal dialysis（PD）patients at four PD centers in Jilin Province and explore the risk factors leading to its poor outcome（catheter removal and/or death）.Methods:Data on patients with PDAP between January 1,2013 and December 31,2019 were collected.Peritonitis rates according to year were compared using Poisson regression analysis.Logistic regression was used to examine the risk factors for catheter removal and PDAP-related death.All patients were divided into two groups according to the period span:2013-2016 group and 2017-2019 group.The spectrum of pathogenic bacteria,the drug susceptible results and its changes were compared between two groups.Results:1.Study population:The study included 1062 PDAP episodes occurred in 611patients.Of these,482 episodes occurred in the 2013-2016 group and 580 episodes in the2017-2019 group.2.Peritonitis incidence rate:The overall incidence rate of PDAP was 0.225episodes/patient-year,which decreased over time（P<0.05）.3.Risk factors for catheter removal:Longer PD duration（odds ratio[OR],1.021;95%confidence interval[CI],1.010–1.032,P<0.001）,more previous PDAP episodes（OR,1.267;95%CI,1.039–1.545,P=0.019）,dialysate white cell count（29）100×10~6/L on day 5 of PDAP（OR,6.088;95%CI,3.277–11.312,P<0.001）were risk factors of PD catheter removal.Comparing with culture negative patients,patients with pseudomonas aeruginosa（OR,4.122;95%CI,1.071–15.874,P=0.039）and polymicrobial infections（OR,3.257;95%CI,1.519–6.982,P=0.002）had a higher risk of PD catheter removal,while coagulase-negative staphylococcus（OR,0.282;95%CI,0.100–0.796,P=0.017）and gram-positive（G+）bacteria infections other than staphylococcus aureus,coagulase-negative staphylococcus,corynebacterium and enterococcus were able to reduce the risk of catheter removal（OR,0.082;95%CI,0.011–0.636,P=0.017）.4.Risk factors for PDAP-related death:Elderly age（OR,1.031;95%CI,1.009–1.054,P=0.006）was a risk factor of PDAP-related death.Comparing with culture negative patients,patients with mycobacterium infections had a 14.635（OR,15.635;95%CI,2.825–86.551,P=0.002）higher odds of PDAP–related death.In contrast,higher hemoglobin levels（OR,0.981;95%CI,0.966–0.996,P=0.015）and albumin levels（OR,0.865;95%CI,0.812-0.921,P<0.001）were able to reduce the risk of PDAP-related death.5.Pathogenic spectrum:Among 1062 episodes of PDAP,433 episodes（40.77%）were G+PDAP,245 episodes（23.07%）were gram-negative（G-）PDAP,82 episodes（7.72%）were polymicrobial PDAP,42 episodes（3.95%）were fungal infections and 10episodes（0.94%）were mycobacterium infections,together with 250 culture-negative PDAP episodes.The culture-negative rate is 23.54%.The comparison of the pathogenic spectrum between the 2013-2016 group and the 2017-2019 group showed that the prevalence of polymicrobial PDAP increased from 5.39%to 9.66%（P=0.010）,and the prevalence of fungal PDAP increased from 1.66%to 5.86%（P<0.001）.6.Antibiotic susceptibility:For G+bacteria,the top five antibiotic resistant rates were penicillin（77.89%）,clindamycin（59.55%）,cotrimoxazole（53.18%）,cefazolin（48.33%）and levofloxacin（34.53%）,respectively,while the top five susceptibility rates were vancomycin（99.39%）,rifampicin（88.26%）,levofloxacin（52.91%）,cefazolin（50.83%）,and cotrimoxazole（46.82%）,respectively.For G-bacteria,the top five antibiotic resistant rates were cefotaxime（45.99%）,piperacillin（37.04%）,ciprofloxacin（33.65%）,gentamicin（27.27%）and ceftriaxone（26.88%）,respectively,while the top five susceptibility rates were amikacin（96.63%）,imipenem（96.36%）,ceftazidime（75.45%）,gentamicin（71.77%）and ceftriaxone（69.89%）.In the past three years,the drug susceptibility rate of G+bacteria to rifampicin had increased,and the drug resistance rate against rifampicin had decreased.The drug susceptibility rate of G-bacteria to piperacillin has increased in the past three years.Conclusions:1.The overall PDAP incidence rates showed a decreasing trend year by year.2.Long duration of PD,more frequent episodes of PDAP characteristics,as well as pseudomonas aeruginosa infections and polymicrobial infections were risk factors for PD catheter removal,whereas coagulase-negative staphylococcus and G+bacteria infections other than staphylococcus aureus,coagulase-negative staphylococcus,corynebacterium and enterococcus were able to reduce the risk of catheter removal.Elderly age and mycobacterium infections are risk factors for PDAP–related death,while higher hemoglobin and albumin levels reduce the risk of PDAP–related death.3.The most common pathogens causing PDAP are G+and G-bacteria.Compared to 2013-2016 group,the prevalence of polymicrobial PDAP and fungal PDAP increased significantly in 2017-2019 group.4.In the past three years,the drug sensitivity rate of G+bacteria to rifampicin had increased,the drug resistance rate against rifampicin had decreased;and the drug sensitivity rate of G-bacteria to piperacillin had increased.