Context: Consumptive hypothyroidism is a rare syndrome resulting from increased catabolism of T(4) and T(3) by increased type 3 iodothyronine deiodinase (D3) activity. Consumptive hypothyroidism has primarily been described as a paraneoplastic syndrome in infants as well as in two adults with D3-expressing tumors.
Objective: The aim of the study was to report the third case of consumptive hypothyroidism in an adult and the first in an athyreotic patient.
Design, setting, and patient: We present a 38-yr-old athyreotic female who was euthyroid on a stable therapeutic dose of thyroid hormone for many years and then developed marked hyperthyrotropinemia, coincident with the discovery of large D3-expressing hepatic vascular tumors. The patient also had low serum T(3) and elevated serum rT(3). Hyperthyrotropinemia transiently worsened after surgical resection of the vascular tumors and then persisted for 3 wk after the operation, despite further increases in levothyroxine therapy.
Intervention: The patient's vascular tumor and adjacent normal liver parenchyma were probed with a polyclonal antibody directed against D3.
Main outcome measures and results: D3 immunostaining of the patient's vascular tumor was positive, with no significant immunoreactivity in the adjacent normal hepatic tissue.
Conclusions: This is the third case report of consumptive hypothyroidism in an adult and the first in an athyreotic individual. This case demonstrates that hyperthyrotropinemia may persist after partial liver resection, possibly from the hepatic resection itself.