title: Dengue hemorrhagic fever: the sensitivity and specificity of the world health organization definition for identification of severe cases of dengue in Thailand, 1994-2005.
abstract: BACKGROUND
  Dengue virus infection causes a spectrum of clinical manifestations, usually classified according to the World Health Organization (WHO) guidelines into dengue fever (DF) and dengue hemorrhagic fever (DHF). The ability of these guidelines to categorize severe dengue illness has recently been questioned.
  
  
  METHODS
  We evaluated dengue case definitions in a prospective study at a pediatric hospital in Bangkok, Thailand, during 1994-2005. One thousand thirteen children were enrolled within the first 3 days after onset of fever and observed with standardized data collection. Cases were classified on the basis of application of the strict WHO criteria. All dengue virus infections were laboratory confirmed. We retrospectively grouped patients on the basis of whether they received significant intervention based on fluid replacement and/or requirements for blood transfusion.
  
  
  RESULTS
  Eighty-five (58%) of 150 persons with DHF, 40 (15%) of 264 with DF, and 73 (12%) of 599 with other febrile illnesses (OFIs) received significant intervention. Sixty-eight percent of dengue cases requiring intervention met strict WHO criteria for DHF. In contrast, only 1% of OFI cases met WHO criteria for DHF. Plasma leakage and thrombocytopenia were the 2 components contributing to the specificity of the WHO case definition and identified dengue cases that required intervention. Hemorrhagic tendency did not reliably differentiate DF and DHF. In DF cases, thrombocytopenia and bleeding were associated with severity.
  
  
  CONCLUSIONS
  Dengue illness is heterogeneous in severity, and severe clinical features occurred in patients whose cases were not characterized as DHF. The WHO case definition of DHF demonstrated sensitivity of 62% and specificity of 92% for identification of dengue illness requiring intervention, without the need for laboratory confirmation of dengue virus infection, in an area of endemicity.
authors.affiliation: University of Massachusetts Medical School, Worcester, MA 01655, USA. anon.srikiatkhachorn@umassmed.edu
authors.forename: Anon
authors.initials: A
authors.lastname: Srikiatkhachorn
authors.forename: Robert V
authors.initials: RV
authors.lastname: Gibbons
authors.forename: Sharone
authors.initials: S
authors.lastname: Green
authors.forename: Daniel H
authors.initials: DH
authors.lastname: Libraty
authors.forename: Stephen J
authors.initials: SJ
authors.lastname: Thomas
authors.forename: Timothy P
authors.initials: TP
authors.lastname: Endy
authors.forename: David W
authors.initials: DW
authors.lastname: Vaughn
authors.forename: Ananda
authors.initials: A
authors.lastname: Nisalak
authors.forename: Francis A
authors.initials: FA
authors.lastname: Ennis
authors.forename: Alan L
authors.initials: AL
authors.lastname: Rothman
authors.forename: Suchitra
authors.initials: S
authors.lastname: Nimmannitaya
authors.forename: Siripen
authors.initials: S
authors.lastname: Kalayanarooj
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D003715:Dengue / Q000175:diagnosis*; D003716:Dengue Virus / Q000302:isolation & purification; D005260:Female; D006776:Hospitals, Pediatric; D006801:Humans; D007223:Infant; D008297:Male; D011446:Prospective Studies; D012680:Sensitivity and Specificity; D019595:Severe Dengue / Q000175:diagnosis*; D012720:Severity of Illness Index; D013785:Thailand; D014944:World Health Organization