Dengue

Revision as of 02:45, 30 October 2016 by Alvarez13 (talk | contribs) (tourniquet test)

Background

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

Clinical Features

  • Incubation 3-7 days
  • Febrile phase:
    • High fever + 'Breakbone' + GI symptoms + rash + possible exposure
    • +/- Faget sign
    • Lasts 3-7 days, majority recover
  • Critical Phase[1]:
    • Minority of patients, generally pediatric and elderly
    • Around time of defervescence
    • Vascular leak, hypoproteinemia, hemoconcentration, pleural effusion, ascites
    • Narrowed pulse pressure, persistent vomiting, RUQ tenderness, lethargy and restlessness are signs of impending collapse
    • Mucosal and skin bleeding
  • "Severe Dengue," any of the following:
    • Shock from plasma leakage
    • Hemorrhage
    • Respiratory distress

Differential Diagnosis

Fever in traveler

Evaluation

Work-up

  • Labs:
    • CBC: Leukopenia, thrombocytopenia, and hemoconcentration
    • CMP: LFTs elevated
    • DIC labs should be sent
    • Diagnose by 4x increase in acute/ convalescent titres - unlikely to be resulted in ED
  • Tourniquet Test - Tests capillary fragility
Example of positive tourniquet test on the right
    • Inflate cuff to pressure between SBP & DBP, and leave for 5 min
    • (+) Test = 10-20 petechiae 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 patients (ie pregnant, elderly, children, chronic disease)
    • ICU - patients with shock and end-organ damage

See Also

References

  1. Simmons, C.P., Farrar, J.J., van Vinh Chau, N. and Wills, B. (2012) ‘Dengue’, New England Journal of Medicine, 366(15), pp. 1423–1432.