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 continuous ambulatory peritoneal dialysis (CAPD)-related peritonitis has been reported in the literature. At our centre too, a highly significant decline in the peritonitis rate was observed after the introduction of the Twin bag in 1990. In a multivariate analysis which we published recently, the Twin bag system, in conjunction with the more frequent use of the swan neck catheter, correlated significantly (p < 0.001) with an increase in the peritonitis-free interval. In the present study we retrospectively analyzed the bacteriological cultures of the peritonitis episodes, the antibiotic treatment prescribed, and the number of hospitalization days (HDs) before (non-Twin bag group; NTG) and after the introduction of the Twin bag system in our centre (Twin bag group; TG). In terms of absolute numbers, the decreased incidence of peritonitis in the TG was due by and large to a decline in all pathogenic micro-organisms, but mostly to a reduction of coagulase-negative staphylocci (CNS) compared with the NTG. The incidence of culture-negative episodes, however, showed no difference between the two groups. Proportionally, there was a significant increase in culture-negative peritonitis in the TG, whereas infections caused by CNS significantly decreased in comparison with the NTG (p < 0.01). The pattern of the antibiotics prescribed, i.e. mono- versus multiple-drug regimes, did not differ between the two groups. Since, of all micro-organisms involved, CNS infections showed the largest decline in absolute numbers, Staphylococcus aureus increased relatively (43%) after the introduction of the Twin bag system. Nonetheless, those peritonitis episodes necessitating hospital 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-associated problems only, was significantly lower in the TG as compared with the NTG (p = 0.001 and 0.0006 respectively).