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Review
. 2018 Mar;18(2):170-174.
doi: 10.7861/clinmedicine.18-2-170.

Pyrexia of unknown origin

Cristina Fernandez  1 , Nick J Beeching  2
Affiliations
Review

Pyrexia of unknown origin

Cristina Fernandez et al. Clin Med (Lond). 2018 Mar.

Abstract

The syndrome of pyrexia of unknown origin (PUO) was first defined in 1961 but remains a clinical challenge for many physicians. Different subgroups with PUO have been suggested, each requiring different investigative strategies: classical, nosocomial, neutropenic and HIV-related. This could be expanded to include the elderly as a fifth group. The causes are broadly divided into four groups: infective, inflammatory, neoplastic and miscellaneous. Increasing early use of positron emission tomography-computed tomography (PET-CT) and the development of new molecular and serological tests for infection have improved diagnostic capability, but up to 50% of patients still have no cause found despite adequate investigations. Reassuringly, the cohort of undiagnosed patients has a good prognosis. In this article we review the possible aetiologies of PUO and present a systematic clinical approach to investigation and management of patients, recommending potential second-line investigations when the aetiology is unclear.

Keywords: diagnosis; fever; fever of unknown origin; pyrexia; pyrexia of unknown origin.

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Figures

Fig 1.
Fig 1.
The relative causes of pyrexia of unknown origin (PUO) in different patient populations expressed as percentages (data from references5,7–11). aMany HIV positive patients have more than one causal diagnosis for PUO and therefore the sum of percentages in this category is >100%. ART = antiretroviral therapy
See this image and copyright information in PMC

Comment in

  • Comment on Pyrexia of unknown origin.
    Monk B. Monk B. Clin Med (Lond). 2018 Aug;18(4):351. doi: 10.7861/clinmedicine.18-4-351a. Clin Med (Lond). 2018. PMID: 30072567 Free PMC article. No abstract available.
  • Response.
    Fernandez C, Beeching NJ. Fernandez C, et al. Clin Med (Lond). 2018 Aug;18(4):351. doi: 10.7861/clinmedicine.18-4-351b. Clin Med (Lond). 2018. PMID: 30072568 Free PMC article. No abstract available.

References

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