The osler medical handbook -john hopkin

Section VIII – Infectious Diseases



Section Editors:
Christopher Hoffmann, MD, MPH   Nicola Zetola, MD


Chapter 53 – Fever of Unknown Origin
Scott Kim, MD   Rachel Damico, MD, PhD   Paul Auwaerter, MD

FAST FACTS
   ▪    The contemporary understanding of fever of unknown origin (FUO) is derived from Petersdorf and Beeson's 1961 characterization of FUO. A stringent definition of FUO is composed of the following criteria[1]: temperature higher than 38.3° C measured on several occasions, 3-week duration (to exclude self-limiting fevers), negative blood cultures, no apparent explanation, and three outpatient visits or three hospital days.
   ▪    Infections, malignancies, and noninfectious inflammatory diseases account for the majority of cases of FUO.
   ▪    In patients older than 65 years, temporal arteritis should be considered early in any evaluation.
   ▪    Patients with FUO who remain undiagnosed after exhaustive study usually have a favorable prognosis. In one study, in a cohort of 61 patients with FUO discharged without diagnosis, the 5-year mortality rate was only 3.2%.[2]