Changes in the peritoneal equilibration test in selected chronic peritoneal dialysis patients.

Fifty-five patients on chronic peritoneal dialysis with two or more peritoneal equilibration tests (PET) performed between 1983 and 1992 with a mean interval of 21.9 +/- 22.7 months were studied retrospectively. Repeated PET were performed when transport changes were suspected rather than routinely. According to the initial PET, there were 16 high (HI), 17 high-average (HA), 15 low-average (LA), and 7 low (LO) transporters. There was a significant decrease in the mean creatinine dialysate to plasma ratio (D/P creatinine) in the HI transporters and an increase in the LA and LO transporters. The mean dialysate to instilled glucose ratio (D/Do) significantly increased in the HI transporters. The change in both the D/P creatinine and the D/Do of an individual strongly and inversely correlated to their respective initial values. The change in D/P creatinine and D/Do were significantly and inversely correlated to each other, indicating an actual transport change. No correlation was found between the change in transport with peritonitis episodes or frequencies. The centripetal [corrected] change of transport toward average described here may explain why low clearances or low ultrafiltration rates due to rapid transport are infrequent causes of peritoneal dialysis technique failure, and why patients who have been dialyzed for a long period are usually HA transporters.