BLACKWATER FEVER 95 



further blood destruction is taking place, and the red 

 corpuscles and haemoglobin are rapidly increasing at 

 a rate sometimes of 400,000 or 500,000 corpuscles per 

 c.mm. per week. Sometimes the pyrexia is due to 

 malaria, as proved by the examination of the blood. 



This secondary fever is probably associated with the 

 metabolic changes due to the absorption and assimila- 

 tion of some of the waste products of the haemolysis, 

 which have been stored up in various organs. The 

 icterus rapidly disappears, the urine remains clear and 

 pale though casts will be present. After this secondary 

 fever has subsided, convalescence is rapid and usually 

 uninterrupted. It is exceptional for anyone who has 

 had blackwater fever to have any malaria attacks for a 

 prolonged period ; probably the corpuscles containing 

 parasites are amongst the first to be destroyed, and so 

 a " cure " of the malaria results. Sometimes, as in a 

 few cases in England, an attack of malaria may occur 

 shortly after the blackwater fever, though a new infection 

 has not occurred. In these cases, in England, where 

 malaria occurs during convalescence, the parasites are 

 usually those of benign tertian malaria, less commonly of 

 subtertian fever. There are few sequelae, but the debility 

 and anaemia persist to some extent for several weeks, and 

 fatal cardiac failure has occurred during convalescence. 



If fluid is not freely supplied the history is very 

 different. The urine, while still loaded with haemo- 

 globin, diminishes in amount, and vomiting becomes 

 incessant. The amount of urine continues to diminish 

 so that only an ounce or less is passed per diem. This 

 urine may become free from haemoglobin and even 

 from albumin, the temperature becomes normal, the 

 anaemia diminishes, but unless the flow of urine is 

 rapidly restored death is certain. This usually occurs 

 in four or five days, or less, but life may be protracted 

 up to ten days. There is no delirium, no convulsions, 

 the mind is clear, and beyond headache, which is not 

 necessarily severe, there are none of the ordinary symptoms 



