Prevalence of microbial colonization in removed peritoneal catheters: a prospective study

We conducted a prospective bacteriologic study of 89 peritoneal catheters removed from 77 peritoneal dialysis patients. Reasons for catheter removal included severe peritonitis (n = 36, Group A), persistent exit-site infection (n = 29, Group B), and dormant, seemingly uninfected catheters (n = 22, Group C). We studied the external cuff (EC) and internal cuff (IC) as well as the catheter tip. In Group A, microbial growth was seen in 86.1% of ECs, 66.7% of ICs, and 67.6% of tips. In cases of positive isolation, concordance was 91.7% IC versus EC, 84.2% IC versus tip, and 80.0% EC versus tip. The peritonitis agent was recovered from 61.1% of ECs, 50.0% of ICs, and 55.6% of tips. In Group B, colonization was seen in 72.4% of ECs, 44.8% of ICs, and 31.0% of tips. When an isolation was obtained from both EC and IC, concordance was 81.8%. The exit-site infection agent was recovered from 69% of ECs and 24% of ICs. In Group C, microbial growth was observed in 77.3% of ECs, 45.5% of ICs, and 31.8% of tips. Gram-positive bacteria predominated, with the same bacteria colonizing EC and IC in 66.7% of cases. In conclusion, removed peritoneal catheters present a high prevalence of extensive microbial colonization, even in the absence of overt infection.