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

Abstract

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.

Biofilms and Infection in Dialysis Patients

“…Morphologic demonstrations of biofilms by EM on PD catheter surfaces were done on explanted PD catheters in several studies (36–39). The patient populations and duration of dialysis varied in these prospective, cross‐sectional studies (36–39).…”

“…Morphologic demonstrations of biofilms by EM on PD catheter surfaces were done on explanted PD catheters in several studies (36–39). The patient populations and duration of dialysis varied in these prospective, cross‐sectional studies (36–39). In the two studies with large numbers of patients (36,37), SEM and transmission electron microscopy (TEM) demonstrated biofilms that were viable in culture (36,37) containing gram‐positive and gram‐negative bacteria which are commonly associated with PD‐associated peritonitis (e.g., S. aureus , S. epidermidis , Pseudomonas , E. coli ) (36,37).…”

“…These morphologic studies convincingly proved that biofilm growth is common on PD catheters. However, they failed to establish a relationship between biofilms and PD peritonitis, leading to the consensus that biofilm formation is common on PD catheters (36,37), but may not be essential for development of peritonitis (38,39). The failure to demonstrate such a relationship was very likely due to study designs based solely on examination of explanted PD catheters that were removed from patients at varying time intervals and for various indications (36–39).…”

“…As discussed earlier, studies of biofilm bacteria are usually done by EM or by confocal laser microscopy in PD patients after explantation of their catheters (36–39). These are research tools and are not suitable for routine use in clinical practice.…”

Biofilm formation byStaphylococcus epidermidison peritoneal dialysis catheters and the effects of extracellular products fromPseudomonas aeruginosa

“…As PD catheters are implanted into the peritoneal cavity, they are immediately covered with a layer of proteins derived from the peritoneal fluid. These can act as adherence sites for bacteria and catheters removed from patients with clinical symptoms of infection have been shown to be covered with microbial biofilms (Dasgupta et al, 1987). Biofilms on PD catheters can be difficult or impossible to eradicate and often consist of mixed microbial populations, which include both Staphylococci and Gram-negative rods (Barraclough et al, 2010).…”