title: Evaluation of predictor variables of diagnostic [18F] FDG-PET/CT in fever of unknown origin.
abstract: BACKGROUND
  Fever of unknown origin (FUO) is defined as an illness having fever which lasts at least 3 weeks of duration and is higher than 38.3 ºC on several measurements. The causes are infections, malignancies, noninfectious inflammatory diseases and miscellaneous. If [18F]FDG-PET/CT helps the final diagnosis, it is called contributory. The aim of the study is to evaluate the predictor variables effecting a contributory PET/CT for the diagnosis.
  
  
  METHODS
  This is a retrospective cohort study conducted between June 2006 and May 2015 including 76 patients. The evaluated predictor variables are age, sex, ESR, CRP, fibrinogen, ferritin, albumin, haemoglobin level, platelet count, total leukocyte count, neutrophil percentage, lymphocyte percentage, ALP, LDH, ALAT, ASAT, GGT, total bilirubin, CK, RF, ANA, urinanalysis, chest radiography, abdominal US, lymphadenopathy, duration of fever, comorbid diseases and previous therapies.
  
  
  RESULTS
  ESR (P=0.001), CRP (P=0.001), fibrinogen (P=0.009), lymphopenia (P<0.001), neutrophilia (P<0.001), ferritin (P<0.001), leukocytosis (P=0.003), duration of fever before PET/CT (<3 months) were found to be statistically significant for positive contribution of PET/CT results to the diagnosis. CONCLUSİONS: [18F]FDG-PET/CT is helpful and contributory for the diagnosis of FUO in patients having higher levels of CRP, ESR, ferritin, fibrinogen, leukocytosis, neutrophilia and shorter durations of fever (<3 months).
authors.affiliation: Department of Nuclear Medicine, Gulhane Military Medical Academy, Ankara, Turkey.
authors.forename: Kursat
authors.initials: K
authors.lastname: Okuyucu
authors.affiliation: Department of Nuclear Medicine, Gulhane Military Medical Academy, Ankara, Turkey.
authors.forename: Engin
authors.initials: E
authors.lastname: Alagoz
authors.affiliation: Department of Internal Medicine, Gulhane Military Medical Academy, Ankara, Turkey.
authors.forename: Seref
authors.initials: S
authors.lastname: Demirbas
authors.affiliation: Department of Nuclear Medicine, Gulhane Military Medical Academy, Ankara, Turkey - since@gata.edu.tr.
authors.forename: Semra
authors.initials: S
authors.lastname: Ince
authors.affiliation: Department of Infectious Diseases, Gulhane Military Medical Academy, Ankara, Turkey.
authors.forename: Ahmet
authors.initials: A
authors.lastname: Karakas
authors.affiliation: Department of Nuclear Medicine, Gulhane Military Medical Academy, Ankara, Turkey.
authors.forename: Ozgur
authors.initials: O
authors.lastname: Karacalioglu
authors.affiliation: Department of Nuclear Medicine, Gulhane Military Medical Academy, Ankara, Turkey.
authors.forename: Bengul
authors.initials: B
authors.lastname: Gunalp
authors.affiliation: Department of Nuclear Medicine, Gulhane Military Medical Academy, Ankara, Turkey.
authors.forename: Nuri
authors.initials: N
authors.lastname: Arslan
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D042241:Early Diagnosis; D005260:Female; D005335:Fever of Unknown Origin / Q000000981:diagnostic imaging*; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008297:Male; D008875:Middle Aged; D000072078:Positron Emission Tomography Computed Tomography; D012189:Retrospective Studies; D055815:Young Adult
chemical_list: D019788:Fluorodeoxyglucose F18