LEI SH MAN I A INFANTUM 



^77 



The identity of infantile kala-azar and canine kala-azar is supported also 

 by Bandi's experiments on agglutination. Animals inoculated by him with 

 cultures of L. infantum developed agglutinins for this species, and nearly 

 in the same amount also for the Leishmania isolated from dogs, and vice versa. 



Franchini states that A nopheles maculipennis can be infected with cultural 

 forms of Leishmania. Gabbi inculpated at one time Musca domestica as a 

 carrier. 



Morphology. — L. infantum so closely resembles L. donovani as 

 to be indistinguishable morphologically. 



Life-History. — It exists in the peripheral blood, bone-marrow, 

 spleen, and liver in children, and suspicion is aroused that it may be 

 spread by fleas, and that aflagellate and flagellate organisms seen in 

 these parasites may be stages in the life-cycle. 



Culture. — It is easily cultivated upon the Nicolle, Novy, MacNeal 

 (or N.N.N.) medium, as was first shown by Nicolle. The organisms 

 develop in the condensation liquid and on the moist surface of the 

 agar. It can be subcultured indefinitely. No distinct differences 

 can be discerned between the three species of Leishmania in culture. 

 L. infantum can to a certain extent be distinguished from L. donovani 

 by the fact that the latter is less easily inoculable with success 

 into dogs. 



Pathogenicity. — It is the cause of infantile kala-azar, and at one 

 time was considered to be the cause of canine kala-azar, which we 

 will now describe. 



Canine Kala-Azar. — ^There are two types of canine kala-azar- — an 

 acute and a chronic. 



Acute canine kala-azar, usually appears in young dogs, when it is 

 associated with fever (39° to 40° C.) of a remittent type, followed by 

 loss of appetite, wasting, tremors, motor disturbance in the hind- 

 limbs, and rarely diarrhoea. The animal finally dies in a comatose 

 condition at the end of three to five months. 



Chronic canine kala-azar begins without any apparent symptoms, 

 except, perhaps, loss in weight, but as it progresses anaemia sets in, 

 and tremors, together with motor disturbances of the hind-limbs, 

 may be noticed. It is therefore milder than the preceding, is very 

 chronic, and associated with considerable enlargement of the spleen. 

 The inoculated dogs have several times been reported to exhibit 

 symptoms resembling dumb rabies. Post-mortem examination 

 exhibits that the spleen has a thickened capsule, with hypertrophy 

 of the lymphoid elements; the epithelium of the blood-lacunae are 

 much hypertrophied, and full of parasites. The liver cells show 

 fatty degeneration; parasites are found in the liver cells and in the 

 endothelium of the lymphatics. The interstitial tissue of the kidney 

 is increased, and parasites occur in the endothelial cells. Parasites 

 may be found in the round-celled infiltration under the capsule of 

 the kidney. The suprarenal bodies show cloudy swelling of the 

 cortical cells, infarcts in the medulla, and vacuolation of the cells, 

 which may be invaded in patches by the parasites. The pancreas 

 showed a hypertrophy of the connective tissue, with the presence 

 of the parasites in the endothelium of the lymphatics. The bone- 



