Dengue

Background

• Aedes mosquito in urban area, especially during rainy seasons in tropical/subtropic regions (Asia, Africa, Central America, Caribbean)
  • Most cases occur in SE Asia
• Dengue shock syndrome and hem fever rare in travelers
  • Caused by second infection of different Dengue serotype

Clinical Features

• High Fever + 'Breakbone' + GI sxs + Rash + possible exposure
  • 4- 7d incubation period → influenza-like prodrome (Fever, headache, myalgias, lymphadenopathy, rash)
  • "Saddle back" fever - high for several days, resolves for several days, then comes back for several days

Differential Diagnosis

Fever in traveler

• Normal causes of acute fever!
• Malaria
• Dengue
• Leptospirosis
• Typhoid fever
• Typhus
• Viral hemorrhagic fevers
  • Ebola virus disease
  • Marburg virus disease
  • Lassa fever
  • Crimean-Congo hemorrhagic fever
• Chikungunya
• Yellow fever
• Rift valley fever
• Q fever
• Amebiasis
• Zika virus

Diagnosis

Work-up

• Labs:
  • CBC: Leukopenia, thrombocytopenia, and hemoconcentration
  • CMP: LFTs elevated
  • DIC labs should be sent
  • Dx by 4x increase in acute/ conv titres - unlikely to be resulted in ED
• Tourniquet Test - Tests capillary fragility
  • Inflate cuff to pressure b/w SBP & DBP, and leave for 5 min
  • (+) Test = 10-20 patechiae per square inch

Evaluation

• Clinical diagnosis

Management

• Supportive Care
  • APAP for pain/fever
    • DO NOT use ASA due to hemorrhagic nature
• IVFs
• Blood Transfusion - consider in hemorrhagic shock

Disposition

• Home - Well hydrated and non-toxic appearing
• Admit - High-risk pts (ie pregnant, elderly, children, chronic dz)
  • ICU - pts with shock and end-organ damage

See Also

• Travel Medicine
• Neglected Tropical Diseases