Pseudomalabsorção de levotiroxina: relato de um caso

Abstract

Uma mulher de 49 anos, em tratamento de hipotireoidismo com levotiroxina, após diagnóstico de tireoidite de Hashimoto e tireoidectomia total para bócio multinodular atóxico, foi avaliada devido a hipotireoidismo persistente apesar do uso de altas doses de levotiroxina (600µg/dia). Clinicamente, a paciente apresentava sinais e sintomas de hipotireoidismo, e os exames laboratoriais mostravam tiroxina livre de 0,20ng/dL; hormônio tireoestimulante de 351µUI/mL; triiodotironina total de 27ng/dL. Foi confirmada a não aderência ao tratamento e considerados os diagnósticos de sindrome de Munchausen e transtorno factício, levando ao quadro de pseudomalabsorção de levotiroxina.A 49-year-old woman who had been treated with sodium levothyroxine because of hypothyroidism after diagnosis of Hashimoto thyroidits and total thyroidectomy for multinodular atoxic goiter was evaluated for persistent hypothyroidism despite the use of large doses of levothyroxine (600µg/day). The patient showed signs and symptoms of hypothyroidism and her laboratory tests were: TSH of 351µUI/mL, free thyroxine of 0.20ng/dL, and total triiodothyronine of 27ng/dL. She was submitted, under medical supervision, to a levothyroxine overload test with no evidence of malabsorption of the thyroid hormone. Diagnosis of factitious disorder and Munchausen syndrome leading to the pseudomalabsorption of levothyroxine was considered.