BACTERIAL AND CLINICAL SEQUELAE OF THE TWIN BAG SYSTEM IN CONTINUOUS AMBULATORY PERITONEAL-DIALYSIS - A SINGLE-CENTER STUDY

Since the introduction of disconnect systems, a marked reduction in co ntinuous ambulatory peritoneal dialysis (CAPD)-related peritonitis has been reported in the literature. At our centre too, a highly signific ant decline in the peritonitis rate was observed after the introductio n of the Twin bag in 1990. In a multivariate analysis which we publish ed recently, the Twin bag system, in conjunction with the more frequen t use of the swan neck catheter, correlated significantly (p < 0.001) with an increase in the peritonitis-free interval. In the present stud y we retrospectively analyzed the bacteriological cultures of the peri tonitis episodes, the antibiotic treatment prescribed, and the number of hospitalization days (HDs) before (non-Twin bag group; NTG) and aft er the introduction of the Twin bag system in our centre (Twin bag gro up; TG). In terms of absolute numbers, the decreased incidence of peri tonitis in the TG was due by and large to a decline in all pathogenic micro-organisms, but mostly to a reduction of coagulase-negative staph ylocci (CNS) compared with the NTG. The incidence of culture-negative episodes, however, showed no difference between the two groups. Propor tionally, there was a significant increase in culture-negative periton itis in the TG, whereas infections caused by CNS significantly decreas ed in comparison with the NTG (p < 0.01). The pattern of the antibioti cs prescribed, i.e. mono- versus multiple-drug regimes, did not differ between the two groups. Since, of all micro-organisms involved, CNS i nfections showed the largest decline in absolute numbers, Staphylococc us aureus increased relatively (43%) after the introduction of the Twi n bag system. Nonetheless, those peritonitis episodes necessitating ho spital admission required an almost identical number of HDs before and after 1990. However, the overall number of HDs per patient-month (HDs /pm), as well as the number of HDs/pm for peritonitis and catheter-ass ociated problems only, was significantly lower in the TG as compared w ith the NTG (p = 0.001 and 0.0006 respectively).