Changing trends in pathogenic bacteria spectrum of peritoneal dialysis-related peritonitis in a single center in 14 years

Abstract

Objective To investigate the changing trends in pathogenic bacteria of peritoneal dialysis-related peritonitis and initial treatment resistance in a single center during the past 14 years. Methods A total of 873 patients undergoing peritoneal dialysis in our department from January 1, 2007 to December 31, 2020 were recruited in this study. Among them, 352 patients had peritonitis, and were divided into 3 groups according to the occurrence time of peritonitis, that is, Period 1 group (P1, January 1, 2007 to December 31, 2012), Period 2 group (P2, January 1, 2013 to December 31, 2016) and Period 3 group (P3, January 1, 2017 to December 31, 2020). The change trends in pathogenic bacteria leading to peritonitis, drug resistance of initial treatment, and treatment outcome in above time periods were analyzed. Results The main pathogens causing peritonitis were Gram-positive bacteria in each time period, among which Staphylococcus epidermidis accounted for the highest proportion (P1: 15.8%, P1: 15.4%, P3: 14%), and had the largest proportion of resistance to initial treatment (P1: 27.3%, P2: 15.6%, P3: 23.3%). From P1 to P3, the frequency of S. aureus was in a trend of increasing, which had significantly higher proportion of P3 than that of P1 (6.7% vs 1.3%, P < 0.05). Among the isolated Gram-negative bacteria, the frequency of Escherichia coli was decreased gradually, and the composition ratio of P3 stage was obviously lower than that of P1 stage (5.7% vs 13.2%, P < 0.05). Alcalibacterium xylogenes was firstly observed from the P2 stage, and then in a decreasing trend in the P3 stage, and its composition ratio was notably lower in the P3 stage than the P2 stage (0.3% vs 2.8%, P < 0.05). Stenotrophomonas maltophilia was firstly observed in the P2 stage and showed an increasing trend, with its composition ratio of the P3 stage remarkably higher than that of the P2 stage (3.2% vs 0.4%, P < 0.05), and its drug resistance ratio was also increased significantly (P2: 1.6 %, P3: 11.1%). The extubation rate of patients who were resistant to initial treatment at each time was significantly higher than that of non-resistant patients (P1: 31.8% vs 7.4%, P2: 35.9% vs 17%, P3: 45.5% vs 20.8%, P < 0.05). Conclusion The pathogenic bacteria that causing peritonitis are mainly Gram-positive bacteria in each time period, with Staphylococcus epidermidis most common, and having highest proportion of resistance to initial treatment. Escherichia coli accounts for the highest proportion in the Gram-negative bacteria, but shows a decreasing trend. Stenotrophomonas maltophilia is a newly emerged pathogen in the P2 stage, and the bacterial resistance ratio is high. At each stage, the extubation rate is significantly higher in the drug-resistant group than the non-resistant group.

Keywords

• peritoneal dialysis
• peritonitis
• changing trends in pathogenic bacteria
• resistance to initial treatment