A90 Dengue fever [classical dengue]

Name of the Condition

• Dengue fever [classical dengue]

Summary

Dengue fever is a viral illness transmitted by mosquitoes, characterized by sudden onset of fever, severe headache, muscle and joint pain, and rash. It is caused by the dengue virus and is common in tropical and subtropical regions. The condition typically resolves within a week but can progress to severe forms in some cases.

Causes

Dengue fever is caused by infection with one of four dengue virus serotypes (DENV-1, DENV-2, DENV-3, or DENV-4). The virus is primarily transmitted to humans through the bite of infected Aedes mosquitoes, most commonly Aedes aegypti. The virus replicates in the mosquito and is passed to humans during feeding.

Risk Factors

• Living in or traveling to areas with high mosquito activity, particularly in tropical or subtropical regions.
• Exposure to standing water, which serves as breeding sites for Aedes mosquitoes.
• Lack of mosquito control measures, such as window screens or insect repellent.
• Previous infection with a different dengue serotype, which may increase the risk of severe disease.

Symptoms

• Sudden high fever (often 104°F or 40°C)
• Severe headache, often behind the eyes
• Muscle and joint pain (myalgia and arthralgia)
• Skin rash, typically appearing 2–5 days after fever onset
• Mild bleeding, such as nosebleeds or gum bleeding
• Fatigue and weakness

Diagnosis

Diagnosis is based on clinical presentation, travel history, and laboratory testing. Blood tests may detect the virus (via PCR) or antibodies (IgM/IgG) to confirm infection. In endemic areas, clinical criteria alone may be sufficient for diagnosis, but laboratory confirmation is preferred when available.

Treatment Options

• Rest and hydration: Adequate fluid intake to prevent dehydration is critical.
• Pain relief: Acetaminophen (paracetamol) for fever and pain; avoid aspirin or NSAIDs due to bleeding risk.
• Monitoring: Close observation for signs of severe dengue, such as plasma leakage or organ impairment.
• Hospitalization: Required for severe cases, including intravenous fluids and supportive care.

Prognosis and Follow-Up

Most patients recover fully within 1–2 weeks. Severe dengue, characterized by plasma leakage, organ impairment, or severe bleeding, can be life-threatening but is manageable with prompt medical care. Follow-up is recommended to monitor for complications, especially in the first 48–72 hours after fever onset.

Complications

• Severe dengue: Includes plasma leakage, shock, and organ failure.
• Bleeding: May range from mild (e.g., petechiae) to severe (e.g., gastrointestinal hemorrhage).
• Organ impairment: Liver, heart, or neurological involvement in rare cases.

Lifestyle & Prevention

• Mosquito control: Eliminate standing water and use insect repellent, screens, or bed nets.
• Protective clothing: Wear long-sleeved shirts and pants in mosquito-prone areas.
• Travel precautions: Check for dengue activity in destination regions and take preventive measures.
• Vaccination: Dengue vaccines are available in some regions for individuals with prior infection.

When to Seek Professional Help

Seek immediate medical attention if you experience:

• Severe abdominal pain
• Persistent vomiting
• Bleeding from gums or nose
• Lethargy or restlessness
• Rapid breathing or cold, clammy skin
• Signs of shock (e.g., weak pulse, low blood pressure)

Tips for Medical Coders

Use code A90 for classical dengue fever. Document the clinical presentation, including fever, headache, myalgia, arthralgia, and rash, to support the diagnosis. Note any severe manifestations (e.g., plasma leakage) for appropriate coding of complications. Ensure documentation aligns with the ICD-10-CM guidelines for viral hemorrhagic fevers.