title: Undiagnosed undifferentiated fever in Far North Queensland, Australia: a retrospective study.
abstract: OBJECTIVE
  This study aimed to describe the causes of acute undifferentiated fever (AUF) and to develop a robust definition of undiagnosed undifferentiated fever (UUDF).
  
  
  METHODS
  This was a retrospective study of AUF over 3 years (2008-2011) in an Australian tertiary hospital. Request for laboratory investigation of one or more infectious agents was used as the search tool.
  
  
  RESULTS
  A total of 340 patients with AUF, aged 15-65 years, were identified over the study period. A final diagnosis was made in 147 (43.2%) patients, dengue fever being the most frequent. The aetiology of fever was not determined in 193 (56.8%) patients. Elevations of C-reactive protein (CRP) and hepatic aminotransferase levels were common in these patients; two patients died. The characteristics of UUDF were fever for ≤21 days and failure to reach a diagnosis after clinical evaluation and specific laboratory investigations.
  
  
  CONCLUSIONS
  The high burden of UUDF argues for a better diagnostic approach to fever that is capable of identifying a broad range of infectious agents.
authors.affiliation: School of Medicine and Dentistry, Faculty of Medicine, Health and Molecular Sciences, James Cook University, Queensland, Australia. Electronic address: tri.susilawati@my.jcu.edu.au.
authors.forename: Tri Nugraha
authors.initials: TN
authors.lastname: Susilawati
authors.affiliation: School of Medicine and Dentistry, Faculty of Medicine, Health and Molecular Sciences, James Cook University, Queensland, Australia.
authors.forename: William John Hannan
authors.initials: WJ
authors.lastname: McBride
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D005335:Fever of Unknown Origin / Q000175:diagnosis* / Q000453:epidemiology / Q000209:etiology; D006801:Humans; D008875:Middle Aged; D011793:Queensland / Q000453:epidemiology; D012189:Retrospective Studies; D055815:Young Adult
keywords: Australia; Epidemiology; Fever; Infectious disease; Investigation