Iodine and Thyroxine Metabolism in Anephric Patients Receiving Chronic Peritoneal Dialysis

Abstract

Iodide and thyroxine metabolism were studied in 5 renoprival patients undergoing chronic, weekly peritoneal dialysis as they were awaiting renal transplantation. The subjects were studied on a clinical research ward after equilibration for a 10- to 13-week period to the hospital diet. Each was dialyzed for approximately 1½ days weekly. Radioiodine kinetic studies conducted during the interval between dialyses indicated that the radioiodine distribution space and the thyroidal uptake rate constant were similar to values in normal subjects. The fecal excretion of iodide and iodide losses in saliva and sweat were increased somewhat. Mean iodine intake and calculated daily thyroidal iodide accumulation were similar to values in normal Arkansas residents. Iodide excretion in the dialysis fluid approximated that normally observed in the urine. Radiothyroxine kinetic studies indicated normal thyroxine distribution and normal fractional thyroxine degradation. Daily thyroxine turnover was significantly above expected values because of increased fecal excretion. Net thyroxine utilization, however, was normal. The serum TBG, thyroxine and TSH concentrations were similar to expected normal values.