What are the indications for hospital admission in a patient with suspected or confirmed dengue fever, particularly those with underlying medical conditions such as diabetes, hypertension, or heart disease?

Indications for Hospital Admission in Dengue Fever

Patients with dengue fever require hospitalization if they exhibit any warning signs (persistent vomiting, abdominal pain/tenderness, clinical fluid accumulation, mucosal bleeding, lethargy/restlessness, hepatomegaly, or rising hematocrit with thrombocytopenia), have severe dengue (plasma leakage, severe bleeding, organ failure, or shock), are pregnant, or have underlying comorbidities such as diabetes with hypertension. 1, 2

Warning Signs Requiring Admission

The following clinical features mandate hospitalization for close monitoring 1, 2:

• Persistent vomiting - inability to tolerate oral fluids 1, 2
• Abdominal pain or tenderness - particularly right upper quadrant pain suggesting hepatic involvement 1, 2
• Clinical fluid accumulation - pleural effusion, ascites, or other evidence of plasma leakage 1, 2
• Mucosal bleeding - epistaxis, gum bleeding, or gastrointestinal bleeding 1, 2
• Lethargy or restlessness - altered mental status or behavioral changes 1, 2
• Hepatomegaly - liver enlargement >2 cm below costal margin 1, 2
• Rising hematocrit with concurrent thrombocytopenia - hematocrit increase >20% from baseline with platelet count ≤100,000/mm³ 1

Severe Dengue Requiring Immediate Hospitalization

Admit immediately to intensive care for 1, 2:

• Dengue shock syndrome - pulse pressure ≤20 mmHg, systolic blood pressure <90 mmHg for >30 minutes, cold/clammy extremities, capillary refill time ≥3 seconds, or elevated lactate >2 mmol/L 2
• Severe plasma leakage - causing respiratory distress or shock 1
• Severe bleeding - gastrointestinal hemorrhage, hematuria, or menorrhagia requiring transfusion 1
• Organ failure - hepatic failure (AST/ALT >1000), renal impairment, or cardiac dysfunction 1

High-Risk Populations Requiring Lower Threshold for Admission

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. This is a critical pitfall to avoid - do not manage pregnant dengue patients as outpatients even if they appear stable.

Patients with comorbidities warrant hospitalization or very close outpatient monitoring 3, 4:

• Diabetes with hypertension - 2.16 times higher risk of dengue hemorrhagic fever (AOR 2.16; 95% CI: 1.18-3.96) 4
• Diabetes alone - 1.78 times higher risk of severe dengue 4
• Heart disease - increased risk of decompensation 3
• Age >60 years - higher risk of complications 3
• Immunocompromised states - increased risk of disease progression 3

Laboratory Criteria for Admission

Admit for close monitoring if 1:

• Platelet count ≤100,000/mm³ with rapid decline 1
• Hematocrit rising >20% from baseline - indicates plasma leakage 1
• Severe thrombocytopenia <25,000/mm³ - associated with clinically significant bleeding (OR 4.7; 95% CI: 0.13-0.9) 5

Notably, 50% of patients with platelet counts between 50,000-80,000/mm³ can be safely managed as outpatients if they lack warning signs and have reliable follow-up 6.

Outpatient Management Criteria (Safe for Discharge)

Patients may be managed as outpatients only if ALL of the following are met 1, 6:

• No warning signs present 1
• Platelet count >100,000/mm³ without rapid decline 1
• Stable hematocrit without hemoconcentration 1
• Tolerating adequate oral fluids (>2500 mL daily) 1
• No comorbidities (diabetes, hypertension, heart disease) 3, 4
• Not pregnant 1
• Reliable daily follow-up available 1
• Lives in setting where isolation is feasible if needed 3

Critical Timing Considerations

Warning signs typically appear around days 3-7 of illness, coinciding with defervescence (when fever subsides) 2. This is the critical phase when plasma leakage occurs. Patients must be counseled to return immediately if fever resolves but warning signs develop - this is a common pitfall where patients mistakenly believe they are improving 2.

Special Considerations for Risk Stratification

Female gender is independently associated with higher bleeding risk (OR 14.5; 95% CI: 0.16-0.56) and should lower threshold for admission in the presence of other risk factors 5.

Chinese ethnicity in Singapore populations showed 1.67 times higher risk of dengue hemorrhagic fever during serotype 2 epidemics 4, though this may not generalize to other populations.

Absolute lymphocyte count >500 on admission is associated with increased bleeding risk (OR 5.7; 95% CI: 1.17-4.99) and should prompt closer monitoring 5.