Spectrum of Unexplained Fever in the Hospitalized Patient

Fever of unclear etiology (FUE) that develops in the hospital is a common reason for infectious-diseases consultation. However, little information is available about the epidemiology of this syndrome. Classic series on fever of unknown origin (FUO) provide limited insight, because most nosocomial FUE patients do not meet the strict case definition of an FUO.

Over a 2-year period at 2 university hospitals and an affiliated VA hospital, 141 patients were hospitalized who met the authors' definition of nosocomial FUE (temperature at least 38.3°C on 3 or more occasions, infection not present or incubating on admission, and uncertain diagnosis after 3 days of investigation). Average duration of fever was 15 days. Infection was found to be respons…