LEISHMANIA DONOVANI 405 



Thus, Donovan (1905, 1909a) states that he had found parasites in the 

 finger blood of over 93 per cent, of the cases in Madras, while Patton 

 (1907, 1912a), in the same place, had positive results in thirty-eight out 

 of forty-five cases. Nicolle and Comte (1908a) in Tunis demonstrated 

 leishmania in the peripheral blood of a case of the Mediterranean disease, 

 and Cannata (1913-1914) in Italy found them in fifteen out of sixteen 

 cases after examination of many films from each, an observation which 

 was confirmed by Vaglio (1914), who was successful in eleven cases. 

 Knowles (1920) has examined cases from this point of view at Shillong in 

 Assam, with the following results: Seventy-three cases were examined, 

 and parasites discovered in the blood of thirty-three. From the seventy- 

 three cases, 682 films were scrutinized, and sixty-seven of these were 

 positive, revealing 2,839 parasites. It will thus be seen that diagnosis by 

 direct examination of the peripheral blood is not always a simple matter, 

 but usually necessitates the careful and prolonged study of many films. 

 Knowles and Das Gupta (1924a) have demonstrated parasites in 67 per 

 cent, of seventy cases by the use of thick films of the peripheral blood. 



Mayer and Werner (1914) and the writer (1914) demonstrated the 

 possibility of diagnosis by culture of the peripheral blood. Blood taken 

 from the finger with due care to avoid bacterial contamination is 

 inoculated to a series of tubes of N.N.N, medium, a few drops being added 

 to each tube. Flagellates develop in the tubes after a variable period of 

 two or three weeks. This observation has been confirmed by Row (1914), 

 Giugni (1914, 1914a), Cannata and Caronia (1914), Cornwall and La 

 Frenais (1916), and Knowles (1920). Though it is a method of diagnosis 

 worthy of trial, a negative result cannot be held to exclude an infection. 

 Culture of material from spleen or liver puncture should be carried out 

 at the time of film-making, for, when the infection is a slight one, the 

 parasites may be missed in the smears, though sufficiently numerous to 

 develop in the culture. 



DIAGNOSIS BY SEROLOGICAL TESTS.— Attempts to obtain a method 

 of diagnosis based on the principle of complement fixation has yielded 

 only discordant results. 



Napier (1921, 1922) noted that if a drop of commercial formalin 

 be added to 1 c.c. of the serum of a case of kala azar, the serum solidifies 

 in a few minutes, and very quickly becomes opaque, like the coagulated 

 white of an egg. This reaction, which is called theformol gel test or aldehyde 

 reaction, is fairly constant in kala azar. It occurs only partially in 

 tuberculosis, leprosy, and heavy malarial infections, and disappears 

 progressively during the course of treatment oi cases of kala azar by 

 means of tartar emetic. 



Bramachari (1920) described as the globulin precipitation test a reaction 



