A 7-year-old boy from Chennai presents with fever, headache, and myalgia for 4 days. On examination, he has a petechial rash on the trunk and a positive tourniquet test. His platelet count is 80,000/μL, haemoglobin 14 g/dL, and haematocrit 42%. AST is 120 U/L and ALT 95 U/L. He is alert and haemodynamically stable. What is the most appropriate next step in management?

Explanation

## Clinical Assessment This child presents with **dengue fever with warning signs** (petechial rash, positive tourniquet test, thrombocytopenia, transaminitis) but remains **haemodynamically stable** with no evidence of plasma leakage or shock. ### Key Point: **Dengue classification in children:** - **Dengue without warning signs:** fever + 2 of (headache, myalgia, arthralgia, rash, leucopenia) - **Dengue with warning signs:** abdominal pain, persistent vomiting, lethargy, liver enlargement >2 cm, bleeding, thrombocytopenia <100,000/μL, haematocrit rise - **Severe dengue (dengue shock syndrome):** plasma leakage (hypotension, narrow pulse pressure, pleural effusion) ± organ failure ### Management Algorithm ```mermaid flowchart TD A[Dengue with warning signs]:::outcome --> B{Haemodynamically stable?}:::decision B -->|Yes| C[Admit for observation]:::action C --> D[Daily platelet + haematocrit monitoring]:::action D --> E[Supportive care + oral rehydration if tolerating]:::action E --> F[IV fluids only if unable to drink or signs of plasma leakage]:::action B -->|No| G[Haemodynamic instability]:::urgent G --> H[IV fluid resuscitation with isotonic crystalloid]:::action H --> I[Transfuse platelets if <20,000/μL or <50,000 with bleeding]:::action ``` ### High-Yield: **Platelet transfusion is NOT indicated in this child because:** - Platelet count 80,000/μL is above the transfusion threshold (typically <20,000/μL or <50,000 with active bleeding) - Transfusion in dengue paradoxically worsens outcomes by increasing plasma volume and precipitating shock - Platelets are consumed by the dengue process; transfused platelets are rapidly destroyed ### Clinical Pearl: **Fluid management in dengue:** - **Maintenance fluids only** in stable dengue with warning signs - **IV fluids (1.5× maintenance)** only if signs of plasma leakage: hypotension, narrow pulse pressure, pleural effusion, rising haematocrit, oliguria - Avoid over-resuscitation — it worsens dengue shock syndrome ### Warning: ~~Prophylactic antibiotics~~ are not indicated in uncomplicated dengue; secondary bacterial infection is rare in the acute phase. NSAIDs and aspirin are contraindicated due to bleeding risk. [cite:Park 26e Ch 10]