Severe Dengue Infection

Dengue virus infection is largely a clinical diagnosis. The WHO-TDR has developed a simplified and binary system of classification for dengue infection. They classify infection as either (1) dengue infection with or without warning signs or (2) severe dengue infection. ^{[2, 14]} Clinicians should suspect dengue infection in patients with possible exposure (travel or endemic) and fever and two of the following characteristics: ^{[2, 14]}

• Nausea/vomiting
• Rash
• Aches and pains
• Positive tourniquet test result
• Leukopenia
• Any warning sign

Warning signs for dengue include the following:  ^{[2, 14]}

• Abdominal pain or tenderness
• Persistent vomiting
• Clinical fluid accumulation
• Mucosal bleeding
• Lethargy, restlessness
• Liver enlargement of more than 2 cm
• Laboratory: Increased hematocrit coupled with rapid decrease in platelet count

Severe dengue infection diagnosis criteria include the following: ^{[2, 14]}

• Severe plasma leakage leading to shock and/or fluid accumulation with respiratory distress
• Severe hemorrhage
• Severe organ impairment

RNA PCR testing is available for DENV1-4 through the CDC for diagnosis during the first 5 days of infection (after this period, IgM ELISA testing is preferred), although this is unlikely to assist directly in emergency department management. ^[2]Information on how to obtain PCR testing in suspected cases can be found at https://www.cdc.gov/dengue/resources/TestpolEng_2.pdf.