What is the management approach for a patient presenting with dengue fever and warning signs?

Management of Dengue with Warning Signs

Patients with dengue and warning signs require immediate hospitalization with close monitoring and intravenous fluid resuscitation to prevent progression to severe dengue and shock. 1

Immediate Classification and Risk Assessment

Upon presentation, immediately classify the patient into one of three categories: dengue without warning signs, dengue with warning signs, or severe dengue, as this determines the entire management approach. 1

Warning signs to identify immediately include: 1

• High hematocrit with rapidly falling platelet count
• Severe abdominal pain or persistent abdominal tenderness
• Persistent vomiting (unable to tolerate oral fluids)
• Lethargy or restlessness
• Mucosal bleeding
• Cold, clammy extremities (early shock)
• Clinical fluid accumulation (pleural effusion, ascites)
• Hepatomegaly >2 cm

The absence of warning signs has a negative predictive value of 91-100% for severe disease, making them clinically useful for risk stratification. 2 However, no single warning sign independently predicts disease progression with high sensitivity. 3 The critical window from onset of warning signs to severe illness is typically within one day in most cases. 2

Hospitalization and Monitoring

All patients with any warning sign should be hospitalized for observation and management. 1, 2 This is essential because approximately 5% of dengue patients develop severe disease, and the critical phase (typically days 3-7 of illness) is when plasma leakage can rapidly progress to shock. 1, 4

Daily monitoring requirements include: 5, 6

• Complete blood count to track platelet counts and hematocrit levels
• Vital signs every 1-4 hours depending on stability
• Urine output monitoring (target >0.5 mL/kg/hour in adults)
• Continuous assessment for progression to severe dengue

For patients with dengue shock syndrome specifically, continuous cardiac telemetry and pulse oximetry are recommended. 5

Fluid Management Strategy

For patients with warning signs but no shock, initiate intravenous isotonic crystalloid fluids. 1 The goal is to maintain adequate perfusion and prevent progression to shock while avoiding fluid overload.

Fluid resuscitation protocol if shock develops: 1

• Administer 20 mL/kg of isotonic crystalloid as a rapid bolus over 5-10 minutes
• Reassess immediately after each bolus for signs of improvement
• If shock persists, repeat crystalloid boluses up to a total of 40-60 mL/kg in the first hour before escalating therapy
• Consider colloid solutions for severe shock with pulse pressure <10 mmHg

Critical pitfall to avoid: Delaying fluid resuscitation in established dengue shock syndrome significantly increases mortality, as cardiovascular collapse may rapidly follow once hypotension occurs. 1 Conversely, administering excessive fluid boluses in patients without shock leads to fluid overload and respiratory complications. 1

After initial shock reversal, fluid removal may be necessary—evidence shows aggressive shock management followed by judicious fluid removal decreased pediatric ICU mortality from 16.6% to 6.3%. 1

Symptomatic Management

Use acetaminophen at standard doses exclusively for pain and fever relief. 5, 6

Never use aspirin or NSAIDs when dengue cannot be excluded, as they worsen bleeding tendencies through platelet dysfunction. 1, 5, 6

Management of Complications

Blood transfusion may be necessary for significant bleeding, with a target hemoglobin >10 g/dL if ScvO2 <70%. 1 Prophylactic platelet transfusion is not recommended, but may be considered in certain cases of active bleeding with severe thrombocytopenia. 1

For persistent tissue hypoperfusion despite adequate fluid resuscitation, vasopressors such as dopamine or epinephrine may be required. 5

If fever persists beyond expected timeframes with hemodynamic instability, obtain blood and urine cultures and chest radiograph to evaluate for secondary bacterial infections, though bacterial co-infection occurs in less than 10% of cases. 5

Special Populations

Pregnant women with confirmed or suspected dengue should be hospitalized regardless of warning signs due to risk of maternal death, hemorrhage, preeclampsia, and vertical transmission. 1, 5 Test pregnant women by NAAT for both dengue and Zika virus, regardless of outbreak patterns. 1, 5 Acetaminophen remains the safest analgesic option for pregnant women. 1, 6

Discharge Criteria

Patients can be safely discharged when ALL of the following criteria are met: 5, 6

• Afebrile for at least 48 hours without antipyretics
• Resolution or significant improvement of symptoms
• Stable hemodynamic parameters for at least 24 hours without support
• Adequate oral intake and urine output (>0.5 mL/kg/hour in adults)
• Laboratory parameters returning to normal ranges (platelets trending upward, hematocrit stable)

Post-discharge instructions: 5

• Monitor and record temperature twice daily
• Return immediately if temperature rises to ≥38°C on two consecutive readings
• Return immediately for persistent or recurrent vomiting, severe abdominal pain, bleeding, lethargy, or cold extremities

Critical Phase Recognition

Failing to recognize the critical phase (typically days 3-7 of illness) when plasma leakage can rapidly progress to shock is a major pitfall. 1 During this phase, patients may appear to improve as fever defervesces, but this is precisely when warning signs emerge and severe dengue develops. 4, 7 The mechanism involves immune-mediated activation leading to excessive cytokine expression, causing increased vascular permeability that may lead to shock, and thrombocytopenia with coagulopathy that can induce hemorrhage. 4