A returning traveler with fever.

Active duty military personnel and civilian government employees are at risk for exposure to a variety of pathogens as they meet their mission requirements throughout the world. When they present with a systemic disease, the clinician must entertain a broad differential diagnosis due to the multitude of infectious, neoplastic, and noninfectious inflammatory disorders that can have similar clinical presentations. Since treatment varies significantly, and lack of appropriate therapy may be deadly, the search for the definitive diagnosis should be aggressive and thorough. We present a case of adult-onset Still's disease (AOSD) masquerading as an infectious disease process in a man with recent travel to Sudan. A discussion of the differential diagnosis is included along with a review of the diagnostic criteria, prognosis, and current therapeutic options for AOSD.