Epidemiology
Etiology
There are 4 dengue virus serotypes, and secondary infection with a different viral serotype is common and is usually associated with more severe illness.
Pathophysiology
Clinical features
- Dengue fever (nonhemorrhagic)
- Flu-like febrile illness with marked myalgia &/or arthralgia
- Often referred to as “break-bone fever”
- Diffuse maculopapular rash
- Retroorbital pain
- Leukopenia
- Flu-like febrile illness with marked myalgia &/or arthralgia
- Severe dengue (hemorrhagic, formally called dengue hemorrhagic fever or DHF)
- DHF typically occurs as a result of an antibody-dependent reaction in patients who are reinfected with a different serotype
- Generally develops as the initial fever subsides (∼ 1 week after onset)
- Temperature change: ranges from hypothermia to a second spike in fever
- Severe hemorrhagic manifestations (e.g., petechiae, ecchymoses, purpura, hematemesis, melena) due to thrombocytopenia (< 100,000/mm3)
- Severely increased vascular permeability
- Pleural effusion, respiratory distress
- Ascites, abdominal pain
- Severe ↑ or ↓ Hct
- Positive tourniquet test (petechiae after sphygmomanometer cuff inflation for 5 min)
- Spontaneous bleeding → shock