Treatment of hyperthyroidism associated with thyrotropin-secreting pituitary adenomas with iopanoic acid.
TSH-secreting tumors comprise less than 2% of all pituitary adenomas. All patients present with hyperthyroidism with a detectable TSH level, and a majority have macroadenomas. Oral cholecystographic agents (e.g. iopanoic acid) potently inhibit the activation of T(4) to the more potent T(3). They have been used successfully to treat primary thyroidal hyperthyroidism and thyroxine overdose. However, they have not been employed in the treatment of central hyperthyroidism. We report, herein, the first two patients with thyrotropinomas, in whom iopanoic acid (Telepaque) has been used perioperatively to safely and rapidly achieve euthyroidism. In case 1, free T(3) index improved from a value of 634 to 175 (normal range 78-162) after 3 d of therapy with iopanoic acid. In case 2, free T(3) by dialysis improved from 697 pg/dl (10.7 pmol/liter) to 195 pg/dl (3.0 pmol/liter) (normal range 210-440 pg/dl; 3.2-6.7 pmol/liter) after 7 d of therapy with iopanoic acid.
Dhillon
Kimvir S
KS
Department of Medicine, Division of Endocrinology, and Gonda Diabetes Center, University of California, Los Angeles School of Medicine 90095, USA.
Cohan
Pejman
P
Kelly
Daniel F
DF
Darwin
Christine H
CH
Iyer
Kris V
KV
Chopra
Inder J
IJ
D000236:Adenoma / Q000150:complications / Q000175:diagnosis / Q000378:metabolism* / Q000601:surgery*; D000328:Adult; D005260:Female; D006801:Humans; D006980:Hyperthyroidism / Q000188:drug therapy* / Q000209:etiology; D007480:Iopanoic Acid / Q000627:therapeutic use*; D008279:Magnetic Resonance Imaging; D008297:Male; D010911:Pituitary Neoplasms / Q000150:complications / Q000175:diagnosis / Q000378:metabolism* / Q000601:surgery*; D011182:Postoperative Care; D011300:Preoperative Care; D013972:Thyrotropin / Q000378:metabolism*
D013972:Thyrotropin; D007480:Iopanoic Acid