LEISHMANIA INFANTUM 



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nuclear, polynuclear, and rarely eosinophile leucocytes, and may be occasion- 

 ally seen in films obtained from the finger even in early stages of the disease, 

 though more frequently near the end. 



Treutlein has stated that the parasite is to be also found in red blood cells, 

 but probably they are merely lying in the concavity of the red corpuscle. 



Life-History. — Multiplication in man takes place by simple binary fission 

 and by multiple division into three or more bodies. Division begins at the 

 broad end, but cytological details are still wanting, and the rest of the life- 

 cycle is unknown. 



Cultivation. — Cultures are obtained by adding the spleen-juice to a sterile 

 sodium citrate solution and incubating at 22° C, as done by Rogers, or the 

 N.N.N, medium may be used (p. 377). 



Inoculation. — Monkeys, rats, and less readily dogs can be infected. 



Pathogenicity, — Leishmania donovani is the cause of Indian kala-azar. 



Archibald's Variety of Leishmania donovani. 



Definition. — Leishmania donovani, which does not readily infect dogs experi- 

 mentally, with signs of a coccal stage in its life-history. There is evidence 

 that infection is by means of water. Habitat, Anglo-Eg5rptian Sudan. 



Remarlss. — This parasite has been investigated by Bousfield, who reported 

 also a natural canine infection therewith (this, however, has not been confirmed 

 by Archibald's many investigations), and also by Marshall, who infected 

 monkeys and performed many careful experiments. Archibald's reasons 

 for believing that this parasite is a variety of L. donovani are: — 



1. Coccal Bodies. — Certain coccal bodies have been noted by Archibald in 

 liver smears obtained from a case clinically simulating kala-azar. Material 

 obtained by liver puncture from this case produced kala-azar when inoculated 

 into a monkey, and Archibald suggests the hypothesis that these coccal bodies 

 represent a stage in the life-history of the Leishman-Donovan parasite. 



2. Epidemiology. — In the Sudan the evidence collected by Archibald does 

 not suggest that the disease is insect-borne. This observer produced the 

 disease in monkeys by carrying out careful feeding experiments, and suggests 

 that the disease may be water-borne, a point which agrees with the observations 

 of Bousfield, Thomson, and Marshall, that the disease exists more commonly 

 in villages situate near water than in those farther away. A large number of 

 domestic animals have been examined by Archibald, and none have been 

 found to act as natural hosts of the virus ; even experimental evidence shows 

 that dogs are not readily susceptible to the virus — a fact which tends to 

 differentiate the parasites of Sudan kala-azar from those of the Mediterranean. 



Clinically the disease resembles that met with in other countries. As an aid 

 to its diagnosis and as indication for splenic puncture being carried out, 

 Archibald records the fact that peripheral blood films from suspected cases 

 show evidence of blood destruction, leucopenia, and increase of large mono- 

 nuclears and large lymphocytes, together with an absence of eosinophiles. 

 The comparative or total absence of eosinophiles are suggestive of the 

 disease; further, during the course of the disease an increase or diminution 

 of the eosinophiles in the peripheral blood is some criterion as to whether 

 recovery from kala-azar is likely to result. 



Leishmania infantum Nicolle, 1908. 



Synonym. — Leishmania donovani Laveran and Mesnil, 1903, pro 

 ■parte. 



History. — In 1904 Cathoire observed peculiar bodies in films 

 from the spleen of a child who had died of an ill-defined malady in 

 Goulette, in Tunisia. These bodies Laveran recognized as L. 

 donovani. In 1905 Pianese announced his discovery of Leishmania 

 bodies in large mononuclear cells in the smears from the liver and 

 spleen of children dying from a type of infantile splenic anaemia, 

 which he proposed to call infantile Leishmania anaemia in order to 



