Peritoneal clearance of inorganic sulfate.

The peritoneal clearance of sulfate was studied in a group of 12 stable CAPD patients and compared to the clearance of other well-studied solutes such as urea, phosphate, and creatinine. For this purpose we obtained 24 h peritoneal dialysate collections and performed a modified 6-hour peritoneal equilibration test. The results showed that the peritoneal clearance of sulfate is very similar to those of creatinine and phosphate but significantly smaller than the clearance of urea. Decreased daily excretion of sulfate in relation to protein catabolic rate was noted and requires further studies to define its mechanisms.