Published online by Cambridge University Press: 15 May 2009
The chief facts learnt from these investigations on blackwater fever are summarised briefly here in the order in which they are detailed in the sections.
1. True jaundice, due to the presence of bile pigment in the plasma, occurred in a high percentage of the cases which ended fatally. Haemoglobinaemia, varying from a deep red coloration of the plasma to a faint tinging, occurred in the acute stages of the disease. There was no evidence of auto-agglutination or auto-haemolysis. The fragility of the red cells was unaltered. No relationship between syphilis and blackwater fever was obtained. Spirochaetes were not demonstrated in the blood in any instance. In the hundred cases in this series, a malarial history was obtained in every instance, and without exception the infection was contracted in the Balkans during 1915–1918. The only blood parasites found were Plasmodium vivax and Plasmodium falciparum.
2. The most important tissue changes were as follows: Fatty degeneration of the myocardium. Reduction of the fat lipoid content of the adrenal gland. Enlargement of the Malpighian corpuscles of the spleen due to various changes in the endothelial centres. Recent or chronic perisplenitis was present in every instance. The other changes in the spleen were numerous and variable and due to blood destruction and malaria. Haemorrhages in the liver tissue and foci of central necrosis, in which reactionary changes had occurred, were met with in many instances. Inspissation of the bile in the gall bladder and bile passages was of common occurrence.
The changes in the kidneys during the acute stages of blackwater fever were very pronounced, but complete recovery rapidly ensued during the period of convalescence without subsequent nephritis as far as the information available indicated. Spirochaetes were not found in any of the tissues in this disease. Scattered haemorrhages occurred in the most rapidly fatal cases.
3. From alcoholic and acetone extracts of the dried residue of the urine, obtained during the period of haemoglobinuria, haemolytic substances were demonstrated. From alcoholic and acetone extracts of the dried organs very active haemolytic substances were obtained, more especially from the acetone extracts.
The alcoholic extracts of the urine were more potent than the acetone in the three cases which recovered. Similar results were not obtained by extracting the dried viscera from cases other than blackwater fever, including malaria.
4. There was no evidence that quinine administered by any method during an attack of blackwater fever increased the severity or influenced the progress of the disease apart from its eftects on malaria. Quinine administered to animals rendered anaemic did not excite haemoglobinaemia. Quinine was obtained from the urine by extraction, during the period of haemoglobinuria, in amounts which corresponded to those obtained in the malarial cases. Rabbits injected with quinine previous to and during the period when both ureters were ligatured failed to develop haemoglobinaemia or haemoglobinuria.
5. The urine in cases of blackwater fever rapidly returns to the normal from the period of haemoglobinuria. Clumps of red cells which possess certain characteristics were found in the urine in some cases. Clumps of red cells were of common occurrence in the tubules of the kidneys. The injection of sterilised urine from cases of blackwater fever obtained during the period of haemoglobinuria failed to produce any ill eftects in animals.
6. Blackwater fever was most frequently met with during the months of March and April, at the time when the temperature was at the commencement of its upward summer rise. No evidence was obtained that blackwater fever is in any way related to anaphylaxis. It was not possible to employ any method to demonstrate whether blackwater fever is due to a filter passer.