Relationship of Adherent Bacterial Biofilms to Peritonitis in Chronic Ambulatory Peritoneal Dialysis

To examine the relationship of the formation of biofilm (adherent bacterial microcolonies) to recurrent peritonitis in patients on continuous ambulatory peritoneal dialysis (CAPO) we examined the surfaces of 25 recovered Tenckhoff (T) catheters by scanning electron microscopy (SEM) and microbiological examination of scrapings. Twelve catheters had been removed after successful transplantation; the patients had not been dialyzed for three months and had no evidence of peritonitis during that period (control group), and only seven had experienced peritonitis (I or 2 episodes) before transplantation. All 13 patients in the study group had experienced repeated episodes of peritonitis (range 3–13, average, 5.6). We detected no significant differences between the control and study groups with respect to the percentage of catheter-surface covered by biofilm, or the proportion of catheter segments whose scrapings yielded positive bacterial cultures. It is concluded that large areas of the T catheters of CAPO patients are colonized by bacterial biofilms but only active dialysis predisposes to recurrent peritonitis.