A 35-year-old man returning from sub-Saharan Africa presents with daily fever spikes, severe anaemia, and haemoglobinuria (blackwater fever). Blood film shows ring forms and banana-shaped gametocytes. Parasitaemia is 12%. Which Plasmodium species and which complication is most likely responsible for the haemoglobinuria?
- A P. falciparum; massive intravascular haemolysis, often quinine-triggered ✓
- B P. vivax; splenic sequestration of RBCs
- C P. malariae; nephrotic syndrome with immune complex deposition
- D P. ovale; haemolysis from relapse episodes
Correct answer: A. P. falciparum; massive intravascular haemolysis, often quinine-triggered
Explanation
Blackwater fever (haemoglobinuria) is associated with P. falciparum malaria, characterised by massive intravascular haemolysis leading to haemoglobin in urine. It was classically precipitated by quinine in individuals with repeated malaria exposure and possible G6PD deficiency. Banana-shaped gametocytes and high parasitaemia are diagnostic of P. falciparum. P. malariae is associated with quartan nephropathy. P. vivax and P. ovale do not typically cause haemoglobinuria.
Reference: Ananthanarayan & Paniker's Textbook of Microbiology, 11th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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