title: Thyrotoxicosis presenting as hypogonadism: a case of central hyperthyroidism.
abstract: Herein, we present a case of central thyrotoxicosis with well-documented serial therapeutic interventions. Thyroid-stimulating hormone (TSH)-secreting pituitary tumors represent a rare cause of hyperthyroidism. It is being diagnosed more frequently with the third-generation TSH assay. Many conditions can produce normal or elevated TSH levels in combination with elevated thyroid hormone levels. The differential diagnosis includes resistance to thyroid hormone (RTH, Refetoff's syndrome), assay interference from anti-T4/T3 and heterophile antibodies, elevated or altered binding proteins, drugs affecting peripheral metabolism, and noncompliance with thyroid replacement therapy. In contrast to RTH, our patient presented had high alpha-subunit-to-TSH molar ratio, failed TSH response to thyrotropin-releasing hormone stimulation, and a large pituitary mass. Normal or high TSH in the presence of elevated T4 or T3 is a fairly common clinical scenario with many etiologic possibilities. This TSH-producing adenoma represents an unusual initial clinical presentation, as hypogonadism appeared before features of thyrotoxicosis were appreciated. This case represents the most modern therapeutic approach to the management of this rare disease. Our patient has done well on octreotide with control of thyrotoxicosis and an additional 30% shrinkage of his tumor mass.
authors.affiliation: University of Tennessee Health Science Center, Division of Endocrinology and Metabolism, Department of Medicine and the Veterans Administration Medical Center (VAMC) Memphis, TN 38104, USA.
authors.forename: R Dale
authors.initials: RD
authors.lastname: Childress
authors.forename: M Nauman
authors.initials: MN
authors.lastname: Qureshi
authors.forename: Meri
authors.initials: M
authors.lastname: Kasparova
authors.forename: Hooman
authors.initials: H
authors.lastname: Oktaei
authors.forename: Beverly
authors.initials: B
authors.lastname: Williams-Cleaves
authors.forename: Solomon S
authors.initials: SS
authors.lastname: Solomon
mesh_terms: D006801:Humans; D006980:Hyperthyroidism / Q000175:diagnosis*; D007006:Hypogonadism / Q000209:etiology*; D008297:Male; D008875:Middle Aged; D015282:Octreotide / Q000627:therapeutic use; D010264:Paraplegia; D013971:Thyrotoxicosis / Q000175:diagnosis* / Q000188:drug therapy; D016896:Treatment Outcome
chemical_list: D015282:Octreotide