FUO

Medical abbreviation · Infectious Disease

FUO
Stands forFever of unknown origin
CategoriesMedical

FUO stands for Fever of unknown origin, an infectious disease abbreviation.

Prolonged fever of 38.3°C (101°F) or higher on several occasions, lasting at least three weeks, without a diagnosis after an appropriate initial evaluation. Causes fall into four groups: infections, cancers (especially lymphoma), noninflammatory and inflammatory diseases such as adult-onset Still's disease, and miscellaneous causes.

Example: FUO workup: three blood cultures, CT chest-abdomen-pelvis, ESR, ferritin; PET-CT if unrevealing.

Usage notes

The classic definition was proposed by Petersdorf and Beeson in 1961, originally requiring a week of inpatient study; later revisions allowed outpatient evaluation. Subcategories include nosocomial, neutropenic and HIV-associated FUO. PET-CT has become a key test, and a substantial share of cases remain undiagnosed yet resolve on their own.

More infectious disease abbreviations

  • DAA – Direct-acting antiviral
  • DOT – Directly observed therapy
  • E. coli – Escherichia coli
  • EBV – Epstein-Barr virus
  • EPT – Expedited partner therapy
  • ESBL – Extended-spectrum beta-lactamase
  • GAS – Group A Streptococcus
  • GC – Gonococcus (gonorrhea)
  • GNR – Gram-negative rods
  • GPC – Gram-positive cocci
  • H1N1 – Influenza A virus subtype H1N1
  • H5N1 – Influenza A virus subtype H5N1

See all 92 infectious disease abbreviations →

Edited by the AbbreviationList.com team. Spotted an error or a missing meaning? Contact us.

This entry is for general education and is not medical advice. Abbreviation use varies between institutions; always confirm in context.