uk-dtmh MCQ (SBA): Plasmodium falciparum Severe Malaria

A 32-year-old British aid worker returns from South Sudan after a 6-month posting. He presents to the emergency department with a 3-day history of high fevers, rigors, headache, and myalgia. He was taking doxycycline prophylaxis but admits to poor adherence over the final month. On examination, his temperature is 39.8°C, heart rate 112 bpm, blood pressure 105/68 mmHg. He is jaundiced with tender hepatosplenomegaly. Blood film shows ring-form trophozoites with some multiply-infected red cells and a parasitaemia of 8%. Haemoglobin is 9.2 g/dL, platelets 42 × 10⁹/L, bilirubin 68 µmol/L, creatinine 185 µmol/L. What is the most appropriate initial treatment?