370 BIOLOGY OF THE PROTOZOA 



and throat, and cause a shocking disease resembling the effects of 

 syphilis except that only soft parts are eaten away. 



Infantile ulcer is also a cutaneous disease and differs from kala 

 azar, which is distinctly a visceral disease, yet serologically the 

 organisms involved are one species only. L. donovani antiserum 

 will agglutinate not only L. donovani but L. infantum as well, while 

 it will not affect L. tropica or L. braziliensis. 



The parasites of kala azar occur in all possible parts of the infected 

 human organism as intracellular forms (Fig. 169, E). These are 

 small (2 ll to 4 ll), round, oval or pyriform bodies, each with a rela- 

 tively large, dense nucleus and a round, ellipsoidal or rod-like body— 

 the blepharoplast— in the cytoplasm. Division stages, 4 ll to 5 ll in 

 diameter, and with double nucleus and blepharoplast, are frequent, 

 showing active multiplication in this non-flagellated stage. They 

 are most numerous in the spleen, liver and bone-marrow but are 

 also plentiful in lymph glands, mesenteries, endothelial cells of 

 bloodvessels, gut wall and skin, but are comparatively rare in the 

 circulating blood where they may be found in macrophages and 

 other cells derived from the endothelial vascular walls. Typical 

 symptoms are irregular fever, anemia, reduced vitality, enormous 

 enlargement of the spleen and frequently of the liver also. Acute 

 cases if untreated usually end in death in a few months, and chronic 

 cases in a year or more. 



Diseases due to L. tropica are much less severe and do not involve 

 the entire human organism, the sores, up to 1 inch in diameter, 

 healing spontaneously within a few months, leaving a characteristic 

 scar. They are usually on exposed portions of the body, e. g., 

 hands, wrists, legs and face, and one infection usually confers 

 immunity (see p. 363). 



South American leishmaniasis is more severe and the clinical 

 symptoms are different, involving not only an initial cutaneous 

 sore, but later infections of the mucous membrane of mouth, nose 

 and throat. The skin lesions are deeper and more persistent than 

 with L. tropica and multiple lesions are more frequent; Torres (1920), 

 for example, reported one South American case in which 248 distinct 

 sores occurred on various parts of the bodv (quoted from Wen von, 

 p. 426). 



Formerly the majority of cases of leishmaniasis ended fatally; 

 today the great majority recover. This is due to treatment with 

 tartar emetic (or the corresponding sodium salt) which was first 

 used with success by Vianno in South American leishmaniasis and 

 later in the same year for cases of kala azar by Di Cristina and 

 Caronia in 1913. Other compounds of antimony have proved 

 useful in combatting resistant forms of Leishmania in spleen, bone- 

 marrow, etc. (see Wenyon, p. 423). 



The transmission of Leishmania is far from established. Experi- 



