[Serum thyrotropin concentrations in patients with Sheehan's syndrome: reevaluation of the usefulness in the diagnosis].
Serum concentrations of thyroid-stimulating hormone (TSH) were determined, using a highly sensitive immunoradiometric assay (IRMA), in 10 patients with Sheehan's syndrome. Serum TSH levels in these patients were from 2.3 to 9.0 microU/ml, with the mean of 6.4 +/- 2.3(SD) microU/ml, and the data were similar to those measured by a conventional RIA method. The levels of serum TSH in these patients were normal or even higher than those of healthy women (1.8 +/- 1.3 microU/ml). After supplement therapy by cortisol, serum TSH levels decreased, but remained within the detectable range that was greater than 0.15 microU/ml. After supplement therapy by 1-thyroxine (T4), serum TSH levels moderately decreased in all patients, and excessive 1-T4 administration resulted in a fall of serum TSH levels to lower than the detectable limit. Thyroidal 123 I uptake was low in 3 out of 6 patients examined, which supports a recent hypothesis of reduced biological activity of the patient's TSH. While, the remaining 3 patients had normal thyroidal 123 I uptake, and administration of perchlorate had no effects on thyroidal radioactivity. Thus, it may be possible that in the former group of patients the TSH has a reduced biological activity, and in the latter group of patients, iodine trapping is intact but further synthesis and secretion of thyroid hormone from the gland are impaired. When the response of serum TSH to TRH was examined, the peak serum TSH levels increased in all patients. The peak TSH levels were 4.8 to 10.2 microU/ml with the mean of 7.5 microU/ml, but the data overlapped with those of normal subjects (peak level ranging 5.9 approximately 27.7 microU/ml).(ABSTRACT TRUNCATED AT 250 WORDS)
D000328:Adult; D005260:Female; D006801:Humans; D006854:Hydrocortisone / Q000627:therapeutic use; D007018:Hypopituitarism / Q000097:blood / Q000175:diagnosis* / Q000188:drug therapy; D008875:Middle Aged; D011237:Predictive Value of Tests; D011863:Radioimmunoassay / Q000379:methods; D013961:Thyroid Gland / Q000378:metabolism; D013972:Thyrotropin / Q000097:blood* / Q000378:metabolism; D013973:Thyrotropin-Releasing Hormone; D013974:Thyroxine / Q000627:therapeutic use
D013973:Thyrotropin-Releasing Hormone; D013972:Thyrotropin; D013974:Thyroxine; D006854:Hydrocortisone