ABSTRACT
Granulocytopenia, which can be seen in patients with Graves' disease during treatment with antithyroid agents, could be a self resolving transient episode or can imply the beginning of life threatening agranulocytosis requiring a change in treatment modality. Transient granulocytopenia could be a manifestation of hyperthyroidism itself, or a mild side effect of antithyroid drugs. Aganulocytosis is a rare, but major complications of the termination drug, propylthiouracil (PTU), requiring prompt termination of the medication, and intensive care. Therefore, differentiation of agranulocytosis and transient granulocytopenia, is important, but is not practically easy. We introduce a case of transient granulocytopenia, which was detected in a patient with Graves'Disease, accompanied by underlying type 1 diabetes mellitus, during treatment with PTU. Diagnosis of transient granulocytopenia was made by a normal granulocyte count following a single injection of G-SCF, and the patient was treated with conservative therapy. This case confirms a diagnostic tool for differentiating transient granulocytopenia and PTU-induced agranulocytosis.