Abstract
Hematopoietic stem cell transplantation (HSCT) is an effective treatment for various types of hereditary hematologic disease, hematological malignancy, primary immunodeficiency and metabolic disease. Thyroid dysfunction is a common complication of HSCT, which situation is mainly manifested as hypothyroidism and rarely as hyperthyroidism. This report presents a 28-yearold man who developed hyperthyroidism 9 years after sibling allogeneic HSCT, which was most likely caused by chronic GVHD. In the meantime, the patient also suffered from liver dysfunction and pancytopenia, for which he was inappropriate to take antithyroid drugs (ATD) for treatment of hyperthyroidism. The patient was orally administered 259 MBq I-131, an individualized dose. The symptoms of hyperthyroidism were mitigated by I-131 treatment.