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Dengue Hemorrhagic Fever/Dengue Shock Syndrome


Thomas M. Yuill

, PhD, University of Wisconsin-Madison

Reviewed/Revised Jun 2023

Dengue hemorrhagic fever is a variant presentation of dengue infection that occurs primarily in children < 10 years living in areas where dengue is endemic. Dengue hemorrhagic fever, which has also been called Philippine, Thai, or Southeast Asian hemorrhagic fever, frequently requires prior infection with the dengue virus.

Dengue hemorrhagic fever is an immunopathologic disease; dengue virus–antibody immune complexes trigger release of vasoactive mediators by macrophages. The mediators increase vascular permeability, causing vascular leakage, hemorrhagic manifestations, hemoconcentration, and serous effusions, which can lead to circulatory collapse (ie, dengue shock syndrome).

Symptoms and Signs of Dengue Hemorrhagic Fever

Dengue hemorrhagic fever often begins with abrupt fever and headache and is initially indistinguishable from classic dengue. Warning signs that predict possible progression to severe dengue include

  • Severe abdominal pain and tenderness

  • Persistent vomiting

  • Hematemesis

  • Epistaxis or bleeding from the gums

  • Black, tarry stools (melena)

  • Edema

  • Lethargy, confusion, or restlessness

  • Hepatomegaly, pleural effusion, or ascites

  • Marked change in temperature (from fever to hypothermia)

Circulatory collapse and multiorgan failure, called dengue shock syndrome, may develop rapidly 2 to 6 days after onset.

Bleeding tendencies manifest as follows:

  • Usually as purpura, petechiae, or ecchymoses at injection sites

  • Sometimes as hematemesis, melena, or epistaxis

  • Occasionally as subarachnoid hemorrhage

Bronchopneumonia with or without bilateral pleural effusions is common. Myocarditis can occur.

Mortality is usually < 1% in experienced centers but otherwise can range to up 30%.

Diagnosis of Dengue Hemorrhagic Fever

  • Clinical and laboratory criteria

Dengue hemorrhagic fever is suspected in children with World Health Organization–defined clinical criteria for the diagnosis:

  • Sudden fever that stays high for 2 to 7 days

  • Hemorrhagic manifestations

  • Hepatomegaly

Hemorrhagic manifestations include at least a positive tourniquet test and petechiae, purpura, ecchymoses, bleeding gums, hematemesis, or melena. The tourniquet test is done by inflating a blood pressure cuff to midway between the systolic and diastolic blood pressure for 15 minutes. The number of petechiae that form within a 2.5-cm diameter circle are counted; > 20 petechiae suggests capillary fragility.

Complete blood count, coagulation tests, urinalysis, liver tests, and dengue serologic tests should be done. Coagulation abnormalities include

  • Thrombocytopenia (≤ 100,000 platelets/mcL [≤ 100 x 109/L])

  • A prolonged prothrombin time (PT)

  • Prolonged activated partial thromboplastin time (PTT)

  • Decreased fibrinogen

  • Increased amount of fibrin split products

There may be hypoproteinemia, mild proteinuria, and increases in aspartate aminotransferase (AST) levels.

Serological diagnosis can be made using the IgM capture enzyme-linked immunosorbent assay (MAC-ELISA). Combined with the dengue virus RNA amplification test, it can provide a diagnosis within the first 1 to 7 days of illness. The plaque reduction neutralization test (PRNT) is specific and sensitive. Titers in acute and convalescent phase serum samples can reliably establish dengue virus infection and may indicate the specific dengue virus type involved. The PRNT requires live dengue viruses for the test and is labor-intensive and expensive. Many laboratories are not able to do the PRNT.

Patients with World Health Organization-defined clinical criteria plus thrombocytopenia ( 100,000/mcL [≤ 100 x 109/L]) or hemoconcentration (Hct increased by 20%) are presumed to have the disease (see the Centers for Disease Control and Prevention's Dengue Virus: Clinical Guidance).

Treatment of Dengue Hemorrhagic Fever

  • Supportive care

Patients with dengue hemorrhagic fever require intensive treatment to maintain euvolemia. Both hypovolemia (which can cause shock) and overhydration (which can cause acute respiratory distress syndrome) should be avoided. Urine output and the degree of hemoconcentration can be used to monitor intravascular volume.

No antivirals have been shown to improve outcome.

Key Points

  • Dengue hemorrhagic fever occurs primarily in children < 10 years living in areas where dengue is endemic and requires prior infection with the dengue virus.

  • Dengue hemorrhagic fever may initially resemble classic dengue fever, but certain findings (eg, severe abdominal pain and tenderness, persistent vomiting, hematemesis, epistaxis, melena) indicate possible progression to severe dengue.

  • Circulatory collapse and multiorgan failure, called dengue shock syndrome, may develop rapidly 2 to 6 days after onset.

  • Diagnose based on specific clinical and laboratory criteria.

  • Maintaining euvolemia is crucial.

More Information

The following English-language resource may be useful. Please note that THE MANUAL is not responsible for the content of this resource.

NOTE: This is the Professional Version. CONSUMERS: View Consumer Version
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