4
cell containing six parasites and Fig. 3 on the. same plate an eosinophil cell containing two ;
in this film I also found a large cell (Plate I, fig. 2) containing forty-nine parasites and a large
mononuclear cell (Fig . 6) containing ten. In the large cell one of the parasites is seen to be
dividing longitudinally ; it is oval in shape measuring 4.5μ and contains two macronuclei at one
pole and two micronuclei lying at opposite sides of the periphery ; its protoplasm stained faintly
blue and had three vacuoles in it. The close apposition to each other of many of the parasites
in this cell suggests recent division of the parasites. A similar cell (Plate I, fig. 4) was found
in a film of finger blood taken from the second patient two days before his death. This cell
contains thirty-two parasites, six of which are seen lying superimposed on the nucleus; its
protoplasm stained dark blue with Romanowsky's stain and was much vacuolated.
Christophers4 had previously found similar cells in films made from the blood in large
veins, femoral, portal, and hepatic, some hours after death ; and from a study of sections of the
spleen and liver of cases of Kala Azar he concluded that these cells are derived from the
vascular endothelium and that they represent the final stages of an endothelial cell which has
become distended and modified by the presence of a large number of parasites. He was able
to trace every gradation of flattened endothelial cell containing only a few parasites to the
enormous cells almost blocking the capillaries in which they lie.
Statharn 5 who has studied the distribution of the Leishman-Donovan body in the tissues
Confirmed these observations of Christophers and pointed out that these swollen endothelial
cells are met with in the liver, spleen, bone marrow and lymphatic glands in toxæmic affections
and hyperplasias of these organs ; the researches of Werigo,6 Gilbert and Carnot 7 and others
have shown that these vascular endothelial cells are phagocytic in character and that they take
up bacteria and malarial pigment.
Marchand and Ledingliam,8 who also noted the occurrence of the parasites in these large
Cells, consider that only same originate from the vascular endothelium and that the majority are
in reality enlarged splenic cells which have taken on a phagocytic action. It is of interest to
note that these large endothelial cells occur in the peripheral circulation of cases of Kala Azar
some days before death, and it seems most probable that the rupture of these cells and the
liberation of the parasites they contain, explains the occurrence of the large numbers of parasites
in the peripheral blood of patients suffering from ulceration of the large intestine. Once the
parasites are set free in the plasma they are immediately taken up by mononuclear, eosinophil
or polymorphonuclear cells.
The presence of these large cells containing numerous parasites in the circulating blood
further suggests the mode of formation of the brawny swellings which often develop in the
later stages of the disease. Captain Long, I.M.S., first drew my attention to a patient in his
ward who developed such a swelling on the lower part of the left leg. This patient had many
parasites in his peripheral blood and was at the time suffering from diarrhœa. A painful swel-
ling about 3 inches in circumference involving the skin and subcutaneous tissue was noticed on
the outer side of his left leg. It gradually increased in size becoming a fluctuating tumour,
and was thought to contain pus but, on being incised, sanious fluid alone exuded. Films of
this fluid stained by Romanowsky's method and carefully examined showed no parasites or
bacteria. I have examined many of these swellings which form in such situations as the face,
back of the neck, chest, gluteal region, thighs, legs, shoulders or ischio-rectal fossa. When on
the cheek they may result in an abscess opening externally or, as is more frequently the
case, develop into cantrum oris. Another patient under observation in Captain Long's ward
suddenly developed, during the later stages of the disease, a swelling in the right cheek, which
in a few days resulted in a large sloughing ulcer in the mouth and later spreading outwards to
the skin destroyed all the soft tissues up to the patient's right eye.
The earliest changes towards the formation of c antrum oris appear therefore to be identical
with the brawny swellings seen in other parts of the body, and it seems probable that they are
produced by a hæmorrhage caused by the blocking of a small vessel by one or more of the
large cells. It can be readily understood that the resulting swellings would be liable to be
invaded by bacteria and to develop into ulcers. The sudden appearance of these swellings also
suggests 'that this explanation of their formation is the probable one.
In the film taken from the patient just before death there were some parasites showing the
earliest changes towards development, and I have on many occasions seen these appearances in
films of peripheral blood. Statham5 h a s a l s o n o t i c e d p a r t i a l d e v e l o p m e n t o f t h e p a r a s i t e s i n
smears taken from the organs of a case of Kale Azar 12 hours after death. The parasites
measure from 4μ to 5μ in length, their protoplasm stains a distinct blue with Romanowsky's
stain and often contains three or more vacuoles ; the macronuclei, also enlarged and stained
less deeply, are seen growing towards the centre of the parasites. Two cells showing these
appearances are figured in a large mononuclear leucocyte in Plate I, fig. 6.
In the same film there was a large body (Plate I, fig . 5) measuring 14p, in length
containing two parasites. This structure which stained deep blue by Giemsa's method was of
a granular nature and appeared to be similar to bodies seen in films of splenic blood, in which
situation they often contain four or more parasites. There is considerable difference of opinion
as to the true nature of these bodies ; Laveran, 9 Mesnil9 and Donovan10 consider they are red