Development of an in-vitro model to study the growth characteristics of Staphylococcus epidermidis in continuous ambulatory peritoneal dialysis

An in-vitro model of peritonitis in continuous ambulatory peritoneal dialys is (CAPD) has been developed which integrates the parameters of environment al gaseous tension, the changing biochemical profile of the dialysate, and the periodic challenge of fresh fluid. Dwell times of 4 h during the day and 10 h at night were used to reflect th e in-vivo situation. Biochemical analysis of dialysate within the model sho wed that the profiles for creatinine, glucose and protein approximated thos e found in patients. Staphylococcus epidermidis growing in synthetic dialys is effluent or pooled dialysis fluid were seen to adapt rapidly to the envi ronment after an initial lag phase; a tendency to aggregate together increa sed over the 50-h period of operation. In conclusion, the results presented here suggest that this in-vitro model creates an environment which is reflective of the in-vivo situation and the refore has potential for the study of peritonitis in CAPD.