title: Fever of unknown origin.
abstract: More than 50 years after the first definition of fever of unknown origin (FUO), it still remains a diagnostic challenge. Evaluation starts with the identification of potential diagnostic clues (PDCs), which should guide further investigations. In the absence of PDCs a standardised diagnostic protocol should be followed with PET-CT as the imaging technique of first choice. Even with a standardised protocol, in a large proportion of patients from western countries the cause for FUO cannot be identified. The treatment of FUO is guided by the final diagnosis, but when no cause is found, antipyretic drugs can be prescribed. Corticosteroids should be avoided in the absence of a diagnosis, especially at an early stage. The prognosis of FUO is determined by the underlying cause. The majority of patients with unexplained FUO will eventually show spontaneous remission of fever. We describe the definition, diagnostic workup, causes and treatment of FUO.
authors.affiliation: Department of Internal Medicine, Radboud University Nijmegen Medical Center, Nijmegen, The Netherlands karin.mulders-manders@radboudumc.nl.
authors.forename: Catharina
authors.initials: C
authors.lastname: Mulders-Manders
authors.affiliation: Department of Internal Medicine, Radboud University Nijmegen Medical Center, Nijmegen, The Netherlands.
authors.forename: Anna
authors.initials: A
authors.lastname: Simon
authors.affiliation: Department of Internal Medicine, Radboud University Nijmegen Medical Center, Nijmegen, The Netherlands.
authors.forename: Chantal
authors.initials: C
authors.lastname: Bleeker-Rovers
mesh_terms: D005335:Fever of Unknown Origin / Q000175:diagnosis* / Q000188:drug therapy / Q000209:etiology; D006801:Humans
keywords: FDG-PET; Fever of unknown origin; connective tissue disease; diagnosis; infection; malignancy; systemic autoinflammatory diseases; treatment