Hyperthyroidism in Growth Hormone Deficient Children Treated with Human Growth Hormone

Abstract

Two children with growth hormone (GH) deficiency developed hyperthyroidism during the course of their therapy with human GH (hGH). The first patient, who had been irradiated for panhypopituitarism due to suprasellar germinoma, was treated with corticosteroid, 1-deamino-8-D-arginine-vasopressin (DDAVP), l-thyroxine (T4) and GH. Eight years after the initiation of therapy, hyperthyroidism developed without any specific symptoms. Laboratory examination revealed elevated thyroid hormone, positive thyrotropin-binding inhibiting immunoglobulin (TBII) and antimicrosomal antibody. The second patient, with optic nerve atrophy treated with GH and l-T4, developed hyperthyroidism after 10 years of therapy. This patient also showed elevated thyroid hormone, positive anti-thyroglobulin antibody, anti-microsomal antibody and TBII. After being treated with mercazol, the thyroid function of both patients became normal.Although diabetes mellitus (DM) and hypothyroidism are occasionally associated with GH treatment, the development of hyperthyroidism has rarely been reported. This hyperthyroidism associated with GH treatment may occur by chance. However, some other factors, which produce autoimmune antibodies, may also involve the development of hyperthyroidism. These two cases caution us that hyperthyroidism can develop even in a patient with secondary hypothyroidism during treatment with GH and l-T4.