A 32-year-old male from rural Odisha presents to the emergency department with a 5-day history of high-grade fever with chills and rigors. Temperature is 39.8°C, pulse 110/min, BP 100/70 mmHg. On examination, he has mild jaundice, hepatosplenomegaly, and no neck stiffness. Peripheral blood smear shows ring forms and trophozoites with Maurer's clefts. Haemoglobin 9.2 g/dL, platelets 65,000/μL, creatinine 2.1 mg/dL, total bilirubin 3.8 mg/dL. What is the most likely diagnosis and the immediate management priority?

Explanation

## Diagnosis: Plasmodium falciparum Malaria with Severe Manifestations ### Clinical Presentation Analysis **Key Point:** The combination of Maurer's clefts on blood smear is pathognomonic for *Plasmodium falciparum*. This organism is responsible for >90% of malaria deaths globally. **High-Yield:** Severe malaria criteria met in this patient: - Acute kidney injury (creatinine 2.1 mg/dL) - Thrombocytopenia (65,000/μL; normal >150,000) - Jaundice with hyperbilirubinemia (3.8 mg/dL) - Hepatosplenomegaly - Anaemia (Hb 9.2 g/dL) ### Parasite Identification | Feature | P. falciparum | P. vivax | P. malariae | |---------|---------------|---------|-------------| | RBC preference | Mature & immature | Young RBCs | Mature RBCs | | Characteristic finding | Maurer's clefts | Schüffner's stippling | Maurer's clefts (fine) | | Fever pattern | Quotidian/irregular | Tertian (48h) | Quartan (72h) | | Severity | Most severe | Mild-moderate | Mild | | Gametocyte shape | Crescent/banana | Oval | Round | **Clinical Pearl:** Maurer's clefts are electron-dense cytoplasmic projections visible on electron microscopy and some Romanowsky stains; they facilitate sequestration in microvasculature, explaining the severity. ### Management Algorithm ```mermaid flowchart TD A[Confirmed/Suspected P. falciparum]:::outcome --> B{Severe malaria criteria?}:::decision B -->|Yes| C[IV Artesunate 2.4 mg/kg at 0, 12h, 24h]:::action B -->|No| D[Oral artemisinin-based combination therapy]:::action C --> E[Follow with ACT after 3 doses]:::action E --> F[Supportive care: fluids, transfusion if Hb <7]:::action F --> G[Monitor for complications]:::outcome ``` **Key Point:** WHO 2019 and Indian guidelines (NVBDCP) mandate **intravenous artesunate** as first-line for severe malaria. It reduces mortality by ~35% compared to quinine. ### Dosing & Monitoring - **IV Artesunate:** 2.4 mg/kg IV/IM at 0, 12, 24 hours, then once daily - **Switch to ACT:** After 3 doses of IV artesunate (once patient can tolerate oral), complete 3-day course - **Supportive:** Fluid resuscitation (avoid overload in AKI), transfuse if Hb <7 g/dL, manage acute kidney injury **Mnemonic: SEVERE malaria = Severe anaemia, Encephalopathy, Renal failure, Elevated lactate, Vomiting, Electrolyte abnormalities, Respiratory distress** [cite:Harrison 21e Ch 219]