| a severe form of malaria characterized by kidney damage and hemoglobinuria resulting in urine that is dark red or black. |

blackwater fever black·wa·ter fever (blāk'wô'tər)
n.
A serious, often fatal complication of falciparum malaria, characterized by the passage of bloody, dark red, or black urine.
blackwater fever
one of the less common yet most dangerous complications of malaria. It occurs almost exclusively with infection from the parasite Plasmodium falciparum. Blackwater fever has a high mortality. Its symptoms include a rapid pulse, high fever and chills, extreme prostration, a rapidly developing anemia, and the passage of urine that is black or dark red in colour (hence the disease's name). The distinctive colour of the urine is due to the presence of large amounts of hemoglobin, released during the extensive destruction of the patient's red blood cells by malarial parasites. Patients frequently develop anemia because of the low numbers of red blood cells. The presence of blood pigments in the blood serum usually produces jaundice early in the course of the disease.
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