[A case of sarcoidosis with muscle nodules]

A 65-year-old man with sarcoidosis, accompanied by muscle nodules, noticed a painless and enlarged nodule in his forearm. MRI of the nodule showed that a star-shaped area of lower signal intensity was surrounded by an area of higher signal intensity. Histological examination showed granulomas composed of multinuclear giant cells and epithelioid cells. Sarcoidosis was diagnosed. Eight months later, he was admitted to our hospital because of enlargement of the nodular region with pain and stiffness. Marked uptake of 67Ga was observed in the right arm and leg. MRI revealed sarcoid nodules in these regions. An enlargement of the higher signal intensity area was observed in the right forearm nodule. We started administration of prednisolone. Forty days later, his symptoms had disappeared and the size of higher signal intensity area of the nodule had reduced dramatically. 67Ga scintigram and MRI were useful for diagnosis and monitoring during therapy in this patient.