Thyroxine Elimination by Peritoneal Dialysis in Experimental Thyrotoxicosis[*]

Abstract

In previous studies (Herrmann et al. 1971) the beneficial effect of peritoneal dialysis (P.D.) in 3 patients with thyroid storm has been shown. Consequently the mechanism of thyroxine (T₄) elimination by P.D. was studied in a series of 200 thyrotoxic rats in greater detail: Male Sprague-Dawley rats were injected subcutaneously with 50 µg T₄/100 gm body weight daily. After 2 and 8 days, 50 ml of a conventional peritoneal dialysis fluid (Peritosteril-H^® were injected intraperitoneally, the fluid remaining for 2 and 8 hours. After 8 days of T₄-injection the serum T₄-concentration had risen to 56.9 ± 8.3 µg% (C.P.B.-analysis according to Murphy). The T₄-concentration fell to 39.1 ± 7.2 µg% after an 8-hour-dialysis period. Half-concentration times of radioactive T₄ under these conditions were considerably less (7.6 ± 1.7 hours) than in thyrotoxic rats without P.D. (13.2 ± 5.7 hours). There was a significant positive linear correlation between the amounts of T₄ in the dialysate and the decrease of serum-T₄-concentrations (r = 0.714 2a < 0.05). An equally positive linear correlation has been found for the amounts of protein in the dialysate and eliminated T₄ (r = 0.810 2a < 0.01).

These results show that, during P.D., T₄ is eliminated predominantly in protein-bound form (confirmed by electrophoresis of the concentrated dialysate after injection of radioactive T₄). Therefore, hemodialysis seems to be less suited as a therapeutic tool than peritoneal-dialysis to extract T₄ from the serum in patients with thyroid storm.

Key words

Thyrotoxicosis - Peritoneal-Dialysis

1 Presented in part at the Fourth International Congress of Endocrinology, Washington, D.C., USA, June 1972

1 Presented in part at the Fourth International Congress of Endocrinology, Washington, D.C., USA, June 1972