Fever three weeks after the flight home

A 31-year-old back from visiting family in West Africa has had rigors every evening for four days. Tonight he is confused.

31-year-old manED, resus bay 2Fictitious educational patient

Returned traveller, day 22No malaria prophylaxis taken

Day 0 · 20:40

Arrival

Four days of fever with rigors, headache and myalgia, worse each evening. Two weeks in a rural village visiting relatives, home 22 days ago, no prophylaxis, no vaccines. Tonight his partner found him confused and could not keep him awake in the car.

Vitals

HR124BP98/60RR26SpO295%T39.8

Examination

Neuro: GCS 13 (E3 V4 M6); no neck stiffness; no focal deficit.
Skin: Jaundiced sclerae; no rash; no petechiae.
Abdomen: Spleen tip palpable, soft abdomen.

Fever in a returned traveller from a malaria-endemic area, now with reduced consciousness. What is the single test that cannot wait?

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