FUO due to sarcoidosis-lymphoma syndrome.

This is a patient who presented as a fever of unknown origin (FUO) due to sarcoidosis-lymphoma syndrome. In favor of sarcoidosis was an elevated angiotensin-converting enzyme level, hypercalciuria, and bilateral hilar adenopathy on chest x-ray and chest CT. CT-guided biopsy of a hilar node revealed B-cell lymphoma. The differential diagnosis of sarcoidosis versus lymphoma and sarcoidosis-lymphoma syndrome as a cause of fever of unknown origin is discussed in this article.