Consistency of the peritoneal equilibration test in a cohort of nonselected Mexican CAPD patients

The peritoneal equilibration test (PET) is a useful tool in continuous ambulatory peritoneal dialysis (CAPD) prescription. PET D/P ratios are reproducible in the same patient when performed within a short period. However, peritoneal transport consistency in nonselected patients over longer periods of time is debated. The PET was performed twice in 19 randomly selected patients (13 female) from a cohort of 55 patients on CAPD for 32 +/- 24 months, age 44 +/- 18 years. Mean time between the first and second PET was 9.6 +/- 4 months. All patients were peritonitis-free at least 6 weeks before each PET. Fifteen patients did not change transport type between the two PETs: 3 low (L), 8 low-average (LA), 3 high-average (HA), and 1 high (H). Only 4 changed: 1 H to HA, 2 LA to HA, and 1 L to LA. In these 4 patients the change was centripetal (towards the mean) and less than 1 SD and not considered clinically significant. No differences between both groups in peritonitis rate, gender, age, time on dialysis, and diabetes mellitus status were observed. Transport type, as evaluated by the PET, was consistent over time in our group of patients.