A Case of Development of Sarcoidosis During Tumor Necrosis Factor-alpha Antagonist Therapy

Etanercept is a soluble receptor fusion protein that inhibits tumor necrosis factor-alpha(TNF-α). The receptor is used widely in the treatment of ankylosing spondylitis, rheumatoid arthritis, sarcoidosis and other indications. For sarcoidosis, it potentially suppresses granuloma formation with TNF-α blocking. On the other hand, recent studies have suggested that paradoxical sarcoidosis can be induced by TNF-α antagonists in some cases. A 42-yearold woman, who was treated with etanercept due to ankylosing spondylitis for 5 years, was admitted because of right suprahilar lymphadenopathy on chest radiography. Chest computed tomography revealed an enlargement of supraclavicular, paratracheal, mediastinal lymph nodes. She was diagnosed with sarcoidosis on the supraclavicular lymph node biopsy, which was non-caseating epithelioid cell granuloma and excluded from similar diseases. She was treated for sarcoidosis with prednisolone instead of etanercept.