Introduction to Pediatric Dengue

Dengue is a febrile infectious disease of viral origin, transmitted by the bite of mosquitoes of the genus Aedes, mostly Aedes aegypti. It is the most common arbovirus in the world, affecting millions of people annually, with a significant impact on the pediatric population in tropical and subtropical regions.

The clinical spectrum of dengue is wide, varying from asymptomatic or mild forms to severe symptoms that can lead to death. Children, especially infants, are particularly vulnerable to developing severe forms of the disease.

Objective of this guide: Provide a practical and updated tool for pediatricians and health professionals, facilitating early identification, adequate classification and timely management of dengue in the pediatric population, with emphasis on fluid therapy and therapeutic management.

Epidemiology

Dengue is endemic in more than 100 countries. The incidence of the disease has increased dramatically in recent decades, with epidemic outbreaks becoming more frequent and extensive. Unplanned urbanization, climate change, and the movement of people and goods contribute to its spread.

There are four serotypes of dengue (DENV-1, DENV-2, DENV-3 and DENV-4). Infection with one serotype confers lifelong homologous immunity, but only temporary and partial cross-immunity against the other serotypes. A secondary infection with a different serotype increases the risk of developing severe forms of the disease.

Pathophysiology

The pathogenesis of dengue is complex and involves the interaction between the virus and the host immune response. In severe forms, the central pathophysiology is increased capillary permeability, which leads to plasma leakage from the intravascular to the extravascular space, resulting in hemoconcentration, hypovolemic shock, and fluid spill into cavities (pleural, peritoneal).

Main mechanisms:

  • Antibody-dependent enhancement (ADE): Previous infection with one dengue serotype can generate non-neutralizing antibodies that, in a secondary infection with a different serotype, can facilitate virus entry into cells and increase viral replication.
  • Excessive immune activation: The dysregulated immune response, with the release of proinflammatory cytokines, contributes to endothelial damage and increased vascular permeability.
  • Coagulopathy: Platelet dysfunction, thrombocytopenia and alteration of coagulation factors can lead to hemorrhagic manifestations.

Clinical Classification of Dengue (WHO 2009)

The 2009 WHO classification is critical for management as it guides risk stratification and place of care.

Patient who lives or has traveled to an area with dengue transmission, presents with fever and 2 or more of the following:

  • Nausea/vomiting
  • Exanthema
  • Myalgias/arthralgias
  • Retroorbital headache/pain
  • Leukopenia
  • Positive tourniquet test
Management: Generally ambulatory.

Any patient with dengue who also has one or more of the following:

  • Intense and continuous abdominal pain
  • Persistent vomiting (≥ 3 in 1 hour or ≥ 4 in 6 hours)
  • Fluid accumulation (ascites, pleural effusion, pericardial effusion)
  • Mucous membrane hemorrhage
  • Lethargy/Restlessness
  • Increased liver size (>2 cm)
  • Progressive increase in hematocrit along with rapid decrease in platelets
Management: Requires observation and hospital management.

Patient with dengue who presents one or more of the following criteria:

  1. Shock (dengue shock syndrome):
    • Rapid and weak pulse, or paradoxical bradycardia.
    • Hypotension.
    • Cold and sticky skin.
    • Slow capillary refill (> 2 seconds).
    • Narrow pulse pressure (< 20 mmHg).
  2. Severe plasma spill: With respiratory distress.
  3. Severe bleeding: According to the doctor's evaluation (e.g. hematemesis, melena, massive bleeding).
  4. Serious organic compromise:
    • Liver: AST or ALT ≥ 1000 IU/L.
    • CNS: Alteration of consciousness (seizures, lethargy, coma).
    • Heart: Myocarditis.
    • Other organs.
Management: Requires emergency management in the intensive care unit.

Management of Dengue Without Warning Signs (Group A)

Indications for Ambulatory Management:

  • It has no warning signs.
  • Good oral tolerance.
  • Absence of comorbidities.
  • You live near a health center and have transportation available.
  • Responsible family member capable of identifying warning signs and taking the child to the hospital.

Key Recommendations:

  1. Oral hydration:
    • Offer plenty of fluids: oral serum, water, fruit juices (except acidic citrus fruits).
    • Avoid dark or red drinks (they can be confused with vomiting or bleeding).
    • Recommended volume: 50-70 ml/kg/day orally, divided. For infants, 10 ml/kg/hour.
  2. Fever control:
    • Paracetamol (acetaminophen): 10-15 mg/kg/dose every 4-6 hours, maximum 60-75 mg/kg/day.
    • Avoid NSAIDs (ibuprofen, aspirin): Risk of bleeding and Reye syndrome.
  3. Repose: Promote bed rest.
  4. Mosquito net: Use a mosquito net to prevent new bites and spread.
  5. Monitoring for alarm signs: Educate parents about the importance of seeking immediate medical attention if any warning signs appear.
    Follow-up visits: Daily, especially between day 3 and 7 of the illness (critical phase).

Management of Dengue With Warning Signs (Group B1 and B2)

Hospitalization Criteria:

  • Presence of any alarm sign.
  • Infants under 1 year of age.
  • Comorbidities (asthma, diabetes, heart disease, sickle cell anemia, etc.).
  • Unfavorable social or geographical conditions.

Intravenous fluid therapy:

Fluid therapy is the cornerstone of dengue management with warning signs to prevent shock. Crystalloid solutions are used.

Golden rule: Administer the minimum effective volume to maintain adequate perfusion and reverse warning signs.
Phase Infusion Rate (ml/kg/hour) Solution Type Duration / Objective
First Bolus (if there are warning signs, but no outright shock) 5-7 ml/kg/hour Crystalloids (0.9% Normal Saline or Lactated Ringer's Solution) 1-2 hours. Re-evaluate.
Maintenance Bolus (if it improves with the first, but alarm persists) 3-5 ml/kg/hour Crystalloids 2-4 hours. Re-evaluate.
Gradual reduction 2-3 ml/kg/hour Crystalloids 2-4 hours. Re-evaluate.
Basal maintenance 1-2 ml/kg/hour (maintenance hydration) Crystalloids Up to 24-48 hours after resolution of the plasma leak.

Strict Monitoring:

  • Vital signs (every 1-4 hours).
  • Diuresis (hourly).
  • State of consciousness.
  • Capillary refill.
  • Hematocrit (every 6-12 hours, more frequent if there is deterioration).
  • Platelets (every 12-24 hours).
Important: Discontinue IV fluids when the patient is afebrile for 24-48 hours without paracetamol, with good oral tolerance, stable hematocrit, and rising platelets.

Fluid Therapy Calculator

This calculator will help you estimate IV fluid volumes for dengue management based on patient weight.

Results:

First Bolus (5-7 ml/kg/h in 1-2h):

Maintenance Bolus (3-5 ml/kg/h in 2-4h):

Gradual reduction (2-3 ml/kg/h in 2-4h):

Basal maintenance (1-2 ml/kg/h):

Management of Severe Dengue (Group C)

Management of Dengue Shock:

Dengue shock is a medical emergency that requires immediate and aggressive attention.

  1. Initial resuscitation (Rapid Bolus):
    • Volume: 20 ml/kg in 15-30 minutes.
    • Solution type: Crystalloids (0.9% Normal Saline Solution or Lactated Ringer's).
    • Aim: Quickly stabilize hemodynamics.
  2. Reassessment and subsequent boluses:
    • If shock persists after the first bolus, repeat 20 ml/kg in 15-30 minutes.
    • Up to 2-3 rapid boluses can be administered.
    • If the shock does not reverse after 3 boluses or worsens: consider the possibility of bleeding or myocarditis.
  3. Post-resuscitation maintenance phase:
    • Once the patient comes out of shock, start crystalloid infusion at 10 ml/kg/hour for 1-2 hours, then progressively reduce to 5-7 ml/kg/hour, then 3-5 ml/kg/hour and finally maintenance.
    • The speed and duration will depend on the clinical response and monitoring parameters.
  4. Management of Severe Bleeding:
    • Transfusion of packed red blood cells if there is significant active bleeding or severe anemia.
    • Prophylactic transfusion of platelets or fresh frozen plasma is not recommended, except in cases of active bleeding that does not respond to fluid therapy or if there is a risk of cerebral bleeding in a patient with very low platelets and coagulation dysfunction.
  5. Management of fluid overload:
    • If there are signs of overload (respiratory distress, crackles, pulmonary edema, massive effusion) after resolution of shock, consider diuretics (furosemide).
    • Monitor water balance strictly.
Critical points:
  • Continuous monitoring in ICU.
  • Early identification and management of complications.
  • Avoid fluid overload, but ensure adequate resuscitation.

Hospital Discharge Criteria

Discharge of a patient with dengue should be based on clinical and laboratory criteria that indicate resolution of the critical phase and recovery.

Criteria for inpatient discharge include:

  • Absence of fever for at least 24-48 hours without the use of antipyretics.
  • Hemodynamic stability without intravenous fluids.
  • Good oral tolerance and adequate diuresis.
  • Obvious clinical recovery (improvement in appetite, mood).
  • Platelet count increasing and stable (usually > 50,000/mm³).
  • Stable hematocrit without the need for IV fluids.
  • Absence of respiratory distress or significant effusions.
  • There are no signs of active bleeding.
Consideration: A medical reevaluation is recommended 24-48 hours after hospital discharge to ensure complete recovery.

Knowledge Evaluation: Therapeutic Management and Fluid Therapy

1. What is the medication of choice to control fever in children with dengue? (1/5)

2. Which of the following is a warning sign in a child with dengue that indicates the need for hospitalization? (2/5)

3. In the initial management of a child in dengue shock, what is the recommended fluid bolus? (3/5)

4. What type of solution is preferred for intravenous fluid therapy in patients with dengue? (4/5)

5. When should intravenous fluid therapy be suspended in a hospitalized dengue patient with warning signs? (5/5)

Bibliographic References