Thromboblastic hyperthyroidism: sensitive monoclonal TSH assay demonstrates suppressed immunoreactive TSH.
We describe a case of frank clinical hyperthyroidism due to hydatidiform mole. This is thought to be due to human chorionic gonadotrophin (hCG) or a closely related molecule produced by the tumour. hCG can cross-react with TSH in older TSH radioimmunoassays causing falsely elevated TSH levels. We demonstrate this does not occur with a chemiluminescent immunometric (monoclonal) TSH assay despite circulating hCG levels greater than 10(6) u/L.
Department of Medicine, Limerick Regional Hospital, Dooradoyle.
B
B
Abuaisha
E
E
Barrett
J
J
O'Hare
D000328:Adult; D000911:Antibodies, Monoclonal; D006063:Chorionic Gonadotropin / Q000097:blood / Q000276:immunology*; D003429:Cross Reactions; D005260:Female; D006801:Humans; D006828:Hydatidiform Mole / Q000097:blood / Q000150:complications*; D006980:Hyperthyroidism / Q000097:blood* / Q000209:etiology; D011247:Pregnancy; D013972:Thyrotropin / Q000097:blood* / Q000276:immunology; D013974:Thyroxine / Q000097:blood; D014594:Uterine Neoplasms / Q000097:blood / Q000150:complications*
D000911:Antibodies, Monoclonal; D006063:Chorionic Gonadotropin; D013972:Thyrotropin; D013974:Thyroxine