What are the Indian guidelines for managing a patient suspected of having Dengue fever?

Management of Dengue Fever: Indian Guidelines

Initial Assessment and Classification

All patients with clinically 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 presenting with fever plus at least one of the following: nausea, vomiting, rash, headache, retro-orbital pain, myalgia, arthralgia, positive tourniquet test, or leukopenia, particularly with travel to or residence in endemic areas within the past 14 days 2
• The typical incubation period is 4-8 days (range: 3-14 days) 3, 2
• Day-biting mosquitoes of the genus Aedes, particularly Aedes aegypti, are the primary vectors 3, 2

Warning Signs Requiring Immediate Recognition

Identify these warning signs immediately as they predict progression to severe disease 1:

• High hematocrit with rapidly falling platelet count 1
• Severe abdominal pain 1
• Persistent vomiting 1
• Lethargy or restlessness 1
• Mucosal bleeding 1
• Cold, clammy extremities (early shock) 1
• A rise in hematocrit of 20% along with continuing drop in platelet count is an important indicator for onset of shock 4

Diagnostic Testing

For Symptoms ≤7 Days

• Order dengue PCR/NAAT on serum as the preferred initial test 2
• If NAAT is negative, proceed to IgM antibody testing 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
• Note that IgG antibodies can persist for months to years after infection, so this result alone does not confirm acute infection 2

Special Considerations

• Document vaccination history to avoid cross-reactivity with other flaviviruses such as yellow fever, Japanese encephalitis, and tick-borne encephalitis 2
• For 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

Management Based on Classification

Dengue Without Warning Signs (Outpatient Management)

Patients without warning signs should receive aggressive oral hydration with target fluid intake of 2,500-3,000 mL daily, acetaminophen for symptom relief, and daily monitoring for warning signs. 2, 1

• Use any locally available fluids including water, oral rehydration solutions, cereal-based gruels, soup, and rice water 5
• Avoid soft drinks due to high osmolality 1, 5
• Encourage 5 or more glasses of fluid throughout the day 5
• Use acetaminophen (paracetamol) only for pain and fever management 5
• Never use aspirin or NSAIDs under any circumstances due to high bleeding risk 2, 1, 5
• Resume age-appropriate diet as soon as appetite returns 5

Daily Monitoring Requirements

• Daily complete blood count monitoring is essential to track platelet counts and hematocrit levels 2, 5
• The absence of thrombocytopenia significantly reduces the probability of dengue 2

Criteria for Safe Outpatient Management

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

Dengue With Warning Signs (Hospitalization Required)

Hospitalize immediately for close monitoring and intravenous fluid therapy when warning signs are present. 2, 1

Indications for Hospitalization

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

Monitoring in Hospital

• Monitor with continuous cardiac telemetry and pulse oximetry for patients with dengue shock syndrome 2
• Watch for clinical indicators 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, and adequate urine output 5
• Frequent recording of vital signs and determinations of hematocrit are important in evaluating results of treatment 4
• Recognize the critical phase (typically days 3-7 of illness) when plasma leakage can rapidly progress to shock 5

Severe Dengue/Dengue Shock Syndrome (ICU Management)

For dengue shock syndrome, administer 20 mL/kg of isotonic crystalloid as a rapid bolus over 5-10 minutes with immediate reassessment after each bolus. 1, 5

Initial Fluid Resuscitation Protocol

• Use Ringer's lactate or 0.9% normal saline as first-line crystalloid 5
• Reassess immediately after the first bolus for signs of improvement (improvement in tachycardia and tachypnea) 5
• If shock persists, repeat crystalloid boluses up to a total of 40-60 mL/kg in the first hour before escalating therapy 1, 5
• Delaying fluid resuscitation in established dengue shock syndrome significantly increases mortality, as cardiovascular collapse may rapidly follow once hypotension occurs 1, 5

When to Escalate to Colloids

• For severe dengue shock with pulse pressure <10 mmHg, consider colloid solutions 2, 5
• Moderate-quality evidence shows colloids provide faster resolution of shock compared to crystalloids alone (RR 1.09,95% CI 1.00-1.19) 5
• Colloids reduce the total volume of initial bolus needed (mean 31.7 mL/kg versus 40.63 mL/kg for crystalloids) 5
• Alternative colloids include gelafundin or albumin if dextran is unavailable 5
• The ideal fluid management should include both crystalloids and colloids (including albumin) 4

Management of Refractory Shock

• For persistent tissue hypoperfusion despite adequate fluid resuscitation, vasopressors such as dopamine or epinephrine may be required 2, 5
• For cold shock with hypotension: titrate epinephrine as first-line vasopressor 5
• For warm shock with hypotension: titrate norepinephrine as first-line vasopressor 5
• Target mean arterial pressure appropriate for age and maintain ScvO2 >70% 5
• 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 5

Monitoring During Resuscitation

• Watch for signs of fluid overload: hepatomegaly, rales on lung examination, or respiratory distress 5
• Stop fluid resuscitation immediately if hepatomegaly or pulmonary rales develop 5
• Rising hematocrit indicates ongoing plasma leakage and need for continued resuscitation, while falling hematocrit suggests successful plasma expansion 5

Post-Resuscitation Fluid Management

• After initial shock reversal, fluid removal may be necessary, as evidence shows aggressive shock management followed by judicious fluid removal decreased pediatric ICU mortality from 16.6% to 6.3% 1, 5
• Do not continue aggressive fluid resuscitation once signs of fluid overload appear; switch to inotropic support instead 5
• Consider continuous renal replacement therapy (CRRT) if fluid overload >10% develops 5

Management of Complications

Bleeding Management

• Blood transfusion may be necessary for significant bleeding 2, 1, 5
• Target hemoglobin >10 g/dL if ScvO2 <70% 1, 5
• Prophylactic platelet transfusion is not recommended, but may be considered in certain cases 1
• Some patients develop DIC and need supportive therapy with blood products (blood, FFP and platelet transfusions) 4

Pleural Effusion and Ascites

• Polyserositis in the form of pleural effusion and ascites are common in dengue shock syndrome 4
• If possible, drainage should be avoided as it can lead to severe hemorrhages and sudden circulatory collapse 4

Secondary Bacterial Infections

• Obtain blood and urine cultures and chest radiograph if fever persists 2
• Bacterial co-infection is reported in less than 10% of viral illness cases 2
• The most critical error is prescribing antibiotics like azithromycin empirically for dengue fever without evidence of bacterial co-infection, which contributes to antimicrobial resistance without providing clinical benefit 2

Special Populations

Pregnant Women

• Hospitalization is recommended for all pregnant women with confirmed or suspected dengue 1
• Test by NAAT for both dengue and Zika virus regardless of outbreak patterns 2, 1
• Acetaminophen remains the safest analgesic option 2, 1

Children

• For children with dengue shock syndrome, administer an initial bolus of 20 mL/kg of isotonic crystalloid over 5-10 minutes 5
• Aggressive crystalloid resuscitation is life-saving and achieves near 100% survival when properly administered 5
• Acetaminophen dosing should be carefully calculated based on weight 2

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 to healthcare facility if temperature rises to ≥38°C on two consecutive readings or if any warning signs develop 2
• If transaminases were elevated 2-5× normal at discharge, repeat complete blood count and liver function tests at 3-5 days post-discharge and monitor transaminases weekly until normalized 2
• If transaminases were >5× normal at discharge, monitor every 3 days initially 2
• Return immediately for persistent or recurrent vomiting unable to tolerate oral fluids 2
• Consider alternative cooling measures such as tepid water sponging if fever recurs rather than increasing acetaminophen dose 2

Critical Pitfalls to Avoid

• Administering excessive fluid boluses in patients without shock leads to fluid overload and respiratory complications 1, 5
• Failing to recognize the critical phase (typically days 3-7 of illness) when plasma leakage can rapidly progress to shock 1, 5
• Continuing aggressive fluid resuscitation once signs of fluid overload appear instead of switching to inotropic support 1, 5
• Using aspirin or NSAIDs, which worsen bleeding tendencies 1, 5
• Delaying fluid resuscitation in patients with dengue shock syndrome 1, 5
• Changing antibiotics or management based solely on persistent fever pattern without clinical deterioration or new findings 2
• Giving routine bolus IV fluids to patients with "severe febrile illness" who are not in shock 5

Prevention

• Vaccination is recommended after a documented initial infection 6
• Meticulous avoidance of mosquito bites is essential 6
• Implementing hydration tents during epidemics can decrease the number of dengue fever hospitalizations 7