19
Para. 14
I shall refer later (paragraph 31) to Brown's pathology of kala-dukh, but
may state here that crescents were found by him in 43 out of the 50 cases
noted.
It is necessary now to mention briefly some of my own experiences in
these respects—the details will be given presently (paragraphs 17 and 18).
Judging from Brown's and Rogers' reports, I expected to find the parasites
readily in most cases of kala-azar ; and I felt that if this were the case the
nature of the disease would scarcely require further discussion. When I
arrived at Nowgong there was a group of cases in the Civil Hospital there, all of
which had been diagnosed kala-azar by Captain McNaught, and all of which
presented the typical symptoms of that disease of the second stage. The livers
and spleens were always greatly enlarged, there were various degrees of anæmia
and emaciation, and occasionally dropsy of the feet, and most of the cases were
suffering from constant fever. The pathological examination gave the follow-
ing results :—
(a) Not a single malaria parasite could be discovered on repeated and
careful examinations of the peripheral blood in the large majority
of the cases, even when fever was present (as was almost always
the case).
(b) Examination of blood taken from the spleen, and sometimes the liver,
during life, showed the presence neither of parasites nor, in most
cases, of the black pigment.
(c) In two out of seven autopsies made on cases which had been diag-
nosed kala-azar by Captain McNaught, neither parasites nor
black pigment could be found in the spleen and liver.
(d) Careful thermometric observation of the patients showed that the
temperature charts gave the curve of constant low fever, and not
of typical malarial fever of any kind.
(e) The yellow pigment was present in the liver in all the autopsies but
one, and was extracted from that organ during life in some of
the cases.
I am not prepared to say that the parasites and black pigment were entirely
absent in those cases — such can never be said with confidence in regard to
patients living in malarious localities ; but I will say that, if present, they were
so scarce that they could not be detected even after very careful search, and
that they must have existed in almost infinitesimally small quantity as compared
with the quantity in which they are found in ordinary recent malarial infections.
These results, then, raised a very grave suspicion that kala-azar, in spite of
its great clinical similarity to paludism, was really something quite different.
It was necessary to make a closer examination of the question.
14. The Special Pathological Problem Presented.—Either kala-
azar is not malarial fever, or it is so, in spite of the frequent absence of parasites
and black pigment in one stage of the disease.
Just as it would have been rash to assume the malarial nature of the
disease on the strength of the symptoms alone, so now it might be equally
unpermissible to reject this pathogenesis on the grounds I have given.
If kala-azar be malarial, and if my observations be sound, it will follow
that the parasites and pigment may be absent at a certain stage of a malarial
infection. Now it may be taken as granted on the authority of every competent
observer that the parasites are present at least in the beginning of every case
of paludism ; and it is generally held that in most cases, if not in all, there is
pigmentation of the organs. How then account for their absence in these
severe cases—at a time, too, when the fever and the general condition of the
patients showed that a morbific agency, whatever it is, was most certainly at
work ?
There is this possible explanation—that kala-azar is malarial fever in
which the original violent parasitic invasion gradually dies out during the first
stage of the disease ; leaving in the second stage an acute tumor of the spleen
and liver, accompanied by a constant secondary or symptomatic fever ; and
finally resulting in a cachexia in the third stage. It would be possible to con-
ceive that the black pigment is eliminated shortly after the disappearance of
the parasites, leaving, however, the surcharge of yellow pigment actually found
at the autopsies.
D2