What are the management recommendations for a patient with suspected or confirmed dengue fever?

Dengue Fever Management

Initial Classification and Risk Stratification

All patients with suspected dengue must be immediately classified into one of three categories—dengue without warning signs, dengue with warning signs, or severe dengue—as this classification determines the entire management approach. 1

• Suspect dengue in any patient with fever plus at least one of: nausea, vomiting, rash, headache, retro-orbital pain, myalgia, arthralgia, positive tourniquet test, or leukopenia, particularly with travel to endemic areas within 14 days 2
• The disease follows a characteristic triphasic course: febrile phase, critical phase (typically days 3-7), and recovery phase 2, 3

Warning Signs Requiring Immediate Recognition

• High hematocrit with rapidly falling platelet count 2, 1
• Severe abdominal pain 2, 1
• Persistent vomiting 2, 1
• Lethargy or restlessness 2, 1
• Mucosal bleeding 2, 1
• Cold, clammy extremities (early shock) 1

Diagnostic Testing

• For symptoms ≤7 days: Order dengue PCR/NAAT on serum as the preferred initial test 2
• For symptoms >7 days: IgM capture ELISA (MAC-ELISA) becomes the primary diagnostic test 2
• Rapid diagnostic tests combining NS1 antigen and IgG have very high positive likelihood ratios and can optimize management 2
• Begin appropriate management immediately without waiting for diagnostic test results 1

Laboratory Monitoring

• Daily complete blood count monitoring is essential to track platelet counts and hematocrit levels 2, 4
• A rise in hematocrit of 20% along with continuing drop in platelet count is an important indicator for onset of shock 5
• The absence of thrombocytopenia significantly reduces the probability of dengue 2

Management by Disease Severity

Dengue Without Warning Signs (Outpatient Management)

Aggressive oral hydration with target fluid intake of 2,500-3,000 mL daily is the cornerstone of outpatient management. 1, 6

• Use any locally available fluids including water, oral rehydration solutions, cereal-based gruels, soup, and rice water 4
• Avoid soft drinks due to high osmolality 4, 1
• Encourage 5 or more glasses of fluid throughout the day 4
• Acetaminophen at standard doses for pain and fever relief 2, 4
• Never use aspirin or NSAIDs due to increased bleeding risk 2, 4, 1
• Resume age-appropriate diet as soon as appetite returns 4

Outpatient Criteria

• Platelet count >100,000/mm³ without rapid decline 2
• Stable hematocrit without evidence of hemoconcentration 2
• No warning signs present 2

Dengue With Warning Signs or Severe Dengue (Hospitalization Required)

Hospitalization Indications

• Severe plasma leakage, severe bleeding, organ failure, or dengue shock syndrome 2
• Narrow pulse pressure ≤20 mmHg or hypotension 2
• Rising hematocrit (>20% increase from baseline) 2
• Thrombocytopenia ≤100,000/mm³, particularly when declining rapidly 2
• Pregnant women with confirmed or suspected dengue 2, 1

Dengue Shock Syndrome Management

For dengue shock syndrome, administer 20 mL/kg of isotonic crystalloid (Ringer's lactate or 0.9% normal saline) as a rapid bolus over 5-10 minutes with immediate reassessment after each bolus. 4, 1

Initial Resuscitation Protocol

• Reassess immediately after the first bolus for signs of improvement (tachycardia, tachypnea, capillary refill) 4
• If shock persists, repeat crystalloid boluses up to a total of 40-60 mL/kg in the first hour before escalating therapy 4, 1
• For severe dengue shock with pulse pressure <10 mmHg, consider colloid solutions (dextran, gelafundin, or albumin) 2, 4
• Moderate-quality evidence shows colloids provide faster resolution of shock (RR 1.09,95% CI 1.00-1.19) and reduce total volume needed (mean 31.7 mL/kg versus 40.63 mL/kg for crystalloids) 4

Monitoring During Resuscitation

• Watch for signs of adequate tissue perfusion: normal capillary refill time, absence of skin mottling, warm and dry extremities, well-felt peripheral pulses, return to baseline mental status, adequate urine output (>0.5 mL/kg/hour in adults) 4
• Rising hematocrit indicates ongoing plasma leakage and need for continued resuscitation 4
• Stop fluid resuscitation immediately if hepatomegaly, pulmonary rales, or respiratory distress develop 4

Management of Refractory Shock

• If shock persists despite 40-60 mL/kg of crystalloid in the first hour, switch from aggressive fluid administration to inotropic support 4
• For cold shock with hypotension: titrate epinephrine as first-line vasopressor 4
• For warm shock with hypotension: titrate norepinephrine as first-line vasopressor 4
• Target mean arterial pressure appropriate for age and maintain ScvO2 >70% 4
• Begin peripheral inotropic support immediately if central venous access is not readily available, as delays in vasopressor therapy are associated with major increases in mortality 4

Post-Resuscitation Management

• After initial shock reversal, judicious fluid removal may be necessary during the recovery phase 4, 1
• Evidence shows aggressive shock management followed by judicious fluid removal decreased pediatric ICU mortality from 16.6% to 6.3% 4, 1
• Consider continuous renal replacement therapy (CRRT) if fluid overload >10% develops 4

Management of Bleeding Complications

• Blood transfusion may be necessary for significant bleeding 2, 4, 1
• Target hemoglobin >10 g/dL if ScvO2 <70% 4, 1
• Prophylactic platelet transfusion is not routinely recommended 1
• Avoid drainage of pleural effusion and ascites as it can lead to severe hemorrhages and sudden circulatory collapse 5

Special Populations

Pregnant Women

• Test by NAAT for both dengue and Zika virus, regardless of outbreak patterns, due to risk of maternal death, hemorrhage, preeclampsia, and vertical transmission 2, 1
• Hospitalization is recommended for all pregnant women with confirmed or suspected dengue 2, 1
• Acetaminophen remains the safest analgesic option 2, 1

Pediatric Patients

• Acetaminophen dosing should be carefully calculated based on weight 2
• The majority of pediatric patients with dengue shock syndrome can be treated successfully with isotonic crystalloid solutions 7
• If colloid is necessary, use medium-molecular-weight preparation with good intravascular persistence and acceptable side-effect profile 7

Discharge Criteria

Patients can be safely discharged when they meet ALL of the following criteria: 2

• Afebrile for ≥48 hours without antipyretics 2
• Resolution or significant improvement of symptoms 2
• Stable hemodynamic parameters for ≥24 hours without support 2
• Adequate oral intake 2
• Adequate urine output (>0.5 mL/kg/hour in adults) 2
• Laboratory parameters returning to normal ranges 2

Post-Discharge Instructions

• Monitor and record temperature twice daily 2
• Return immediately if temperature rises to ≥38°C on two consecutive readings or if any warning signs develop 2
• Return immediately for persistent or recurrent vomiting unable to tolerate oral fluids 2
• Repeat complete blood count and liver function tests at 3-5 days post-discharge 2
• If transaminases were elevated 2-5× normal at discharge, monitor weekly until normalized 2
• If transaminases were >5× normal at discharge, monitor every 3 days initially 2

Critical Pitfalls to Avoid

• Delaying fluid resuscitation in established dengue shock syndrome significantly increases mortality, as cardiovascular collapse may rapidly follow once hypotension occurs 4, 1
• Administering excessive fluid boluses in patients without shock leads to fluid overload and respiratory complications without improving outcomes 4, 1
• Failing to recognize the critical phase (typically days 3-7 of illness) when plasma leakage can rapidly progress to shock 4, 1
• Continuing aggressive fluid resuscitation once signs of fluid overload appear instead of switching to inotropic support 4, 1
• Using aspirin or NSAIDs, which worsen bleeding tendencies 2, 4, 1
• Prescribing antibiotics empirically without evidence of bacterial co-infection, as bacterial co-infection occurs in less than 10% of cases 2
• Changing management based solely on persistent fever pattern without clinical deterioration or new findings 2
• Blood pressure alone is not a reliable endpoint in children 4

Prevention

• Day-biting mosquitoes of the genus Aedes (particularly Aedes aegypti and Aedes albopictus) are the primary vectors 2, 3
• Vaccination is recommended after a documented initial infection 3
• Meticulous avoidance of mosquito bites 3