Here are the answers to this week's case:
Clinical syndrome - "blackwater fever" associated with hemoglobinuria and renal failure
Most common species to cause this - Plasmodium falciparum
Cause of the dark color - free hemoglobin due to intravascular hemolysis of infected erythrocytes.
This is fortunately a rare syndrome today, although it may be seen in non-immune adults with severe P. falciparum malaria. Hemoglobinuria may also be seen in children and adults in endemic areas but is not usually accompanied by renal failure. Interestingly, blackwater fever seems to be strongly associated with the use of quinine in patients with P. falciparum malaria, as well as in patients with G6PD deficiency.