Usefulness of fluorodeoxyglucose-positron emission tomography in a case of pleural sarcoidosis

BACKGROUND: Pleural sarcoidosis is not a rare disease, and some patients with sarcoidosis experience chest pain, although the cause is often unknown. Various studies have indicated that fluorodeoxyglucose-positron emission tomography (FDG-PET) is useful for diagnosing and monitoring sarcoidosis. CASE: A 62-year-old man noted left-side dominant chest and back pain, although chest computed tomography (CT) revealed no abnormalities. Two months later, chest and back pain rapidly increased in severity and blurred vision appeared. In addition to uveitis, renal dysfunction was observed and chest CT on admission revealed enlargement of bilateral hilar/mediastinal lymph nodes and diffuse small nodular opacities and subpleural nodules, mainly in the segment of the left upper lobe (S1+2). FDG-PET revealed intense FDG uptake in bilateral peripheral lung parenchyma, spread widely along the subpleura and right inguinal lymph nodes with high uptake in the hilar and mediastinal lymph nodes. Sarcoidosis was diagnosed by transbronchial lung biopsy and renal biopsy. Oral corticosteroid treatment was performed due to persistent chest and back pain and rapid progression of renal dysfunction. Chest and back pain immediately disappeared and renal function improved. Follow-up FDG-PET performed 2 months after corticosteroid treatment revealed no areas of intense FDG uptake.