Fever of unknown origin: A rheumatologic perspective

Abstract

Fever of Unknown Origin (FUO) is a syndrome defined by persistent fevers above 38.30C that lasts for longer than 3 weeks with no obvious source. It usually poses a diagnostic challenge to the clinician.

We describe a case of FUO in a young male adult who was treated several times with antibiotics and anti-malarial with no resolution of symptoms. A diagnosis of Adult Onset Still’s Disease (AOSD) was made after thorough investigation. A methylprednisolone pulse therapy relieved the fevers and maintenance therapy continued with methotrexate.

Adult Onset Still’s Disease is a multi-systemic inflammatory disorder that can manifest as FUO and should be suspected if the fever does not respond to therapy.