Hyperthyroidism due to non-tumoural inappropriate TSH secretion. Effect of a long-acting somatostatin analogue (SMS 201-995).
Inappropriate hypersecretion of TSH was investigated in a 25 year old man whose hyperthyroidism had relapsed 4 years after subtotal thyroidectomy. Serum TSH levels were further increased by both TRH and metoclopramide and were partially suppressed by triiodothyronine (120 micrograms/day). The serum alpha-subunit: TSH molar ratio was less than 1.0, and computerised axial tomography showed no evidence of a pituitary tumour. These features are characteristic of inappropriate TSH secretion due to thyrotroph resistance to thyroid hormones. A long-acting somatostatin analogue (SMS 201-995), 50 micrograms injected sc twice-daily for three days, suppressed TSH levels and nearly normalised thyroid hormone levels. Somatostatin analogues may be therapeutically useful in thyrotoxicosis due to non-tumoural inappropriate TSH hypersecretion.
D000328:Adult; D006801:Humans; D006980:Hyperthyroidism / Q000097:blood / Q000188:drug therapy* / Q000209:etiology; D008297:Male; D015282:Octreotide; D013004:Somatostatin / Q000031:analogs & derivatives* / Q000627:therapeutic use; D013963:Thyroid Hormones / Q000097:blood; D013972:Thyrotropin / Q000378:metabolism*; D013997:Time Factors
D013963:Thyroid Hormones; D013004:Somatostatin; D013972:Thyrotropin; D015282:Octreotide