Classification and Diagnosis of Dengue Fever

Traditional WHO Classification

• The World Health Organization traditionally categorized dengue into Dengue Fever (DF), Dengue Hemorrhagic Fever (DHF grades I-IV), and Dengue Shock Syndrome (DSS), with DHF defined as an acute febrile illness with minor or major bleeding phenomena, thrombocytopenia, and evidence of plasma leakage, and DSS including all criteria for DHF plus hypotension or narrow pulse pressure 1, 2, 3, 4, 5

Revised WHO Classification

• The World Health Organization revised classification system categorizes dengue into three groups based on clinical severity: Dengue without Warning Signs, Dengue with Warning Signs, and Severe Dengue, with Severe Dengue defined as dengue with severe plasma leakage, severe bleeding, or organ failure 6, 7

Diagnostic Considerations

• Laboratory confirmation of dengue remains important through PCR, NS1 antigen detection, or IgM antibody testing, and daily monitoring of complete blood count is essential to track platelet counts and hematocrit levels 6, 7, 8

Clinical Application

• The presence of any warning sign warrants close monitoring and consideration for hospitalization, and warning signs typically appear around day 3-7 of illness, coinciding with defervescence 6, 7