15
Para. 12
Society [11, p. 280] forcibly suggested this. Nevertheless it is quite obvious
that, whatever effects these worms can and do produce, they cannot and do not
produce the high fever with sudden onset and the great enlargement of the liver
and spleen which are the characteristics of kala-azar. Even if a theory of
intoxication may lead us to suppose hypothetically that they may do so, we
know, as a fact, that they do not. These worms exist in Europe and in many
places and individuals where anything like the symptoms of kala-azar are
quite unknown. In short, all of them must be exonerated from being the
pathogenetic agents of the disease.
I propose then to exclude further discussion of the question from this
report. How far ankylostomes complicate individual cases of kala-azar will be
examined in paragraph 41.
12. Survey of the Question. -To judge from the symptoms already given,
what strikes us as being possibly the nature of kala-azar?
The reply must be that of all known diseases kala-azar, as described
in paragraph 6, has the closest resemblance to the disease produced by the
protozoal parasites of the red corpuscle, that is, to malarial disease. The sudden
accession of high fever, of remittent or intermittent type, the frequent recurrence
of similar attacks, the gradual tumefaction of the spleen and liver, even the
occurrence of epistaxis and the final cachexia, may be said to correspond
exactly and in every way with the classical symptoms of that disease ; in other
words, kala-azar is prima facie malarial fever. And this view is further sub-
served by the fact that it exists in a region known to be malarious.
So cogent are these arguments, so close the similarity of the symptoms, that
one might easily be tempted to declare the disease malarial fever without further
preface - more so, perhaps, on actual view of the patients than from any written
description. At any rate, the resemblance is so marked that until and unless
malaria, as the cause of the disease, has been weighed and found wanting, it
will be supererogatory to search for other factors.
But, it must now be carefully pointed out, a careful scrutiny of this
kind is required before the malarial nature of the disease can be entirely
accepted. In the first place, though this close resemblance exists, there are
points at which the diseases appear to differ, and this has been felt so much
that some people still cannot admit their identity. The high fatality of kala-azar,
its intractability to quinine, and, above all, its communicability, have all been
quoted as emphasising the difference ; to these may, perhaps, be added the
existence of a continued fever in the second stage of the malady.
Again, however close the resemblance of the two diseases as regards their
grosser symptoms may be, the pathological anatomy and essential nature of the
two may be quite different. Although it is certainly most improbable-to
judge from our general experience in medicine - that two distinct diseases
should produce a long train of identical symptoms, the thing is possible and
must be guarded against.
For example, looking critically at the symptomatology, and remembering
that the early days of the disease have rarely been studied by medical men, we
may suggest that the clinical picture elaborated in paragraph 6 may not be quite
correct in one particular - that the enlargement of liver and spleen may in fact
precede the appearance of the fever - that this fever may in reality be not at all
remittent or intermittent at first as supposed, but continued throughout, as it
is later. Such a history, if it were the true one, would entirely disconcert the
malarial theory, and would tend to exhibit the disease as primarily one of the
spleen and liver accompanied by a secondary fever.
This view would be very compatible with, the facts - supposing the history
slightly changed as indicated. We might imagine almost any pathogenesis for
the primary disease of the organs. We might conjecture the existence of a
cirrhotic foie infectieux, and ascribe for it the pathogenesis which Adami gives
of the Pictou cattle disease or something similar. Or we might attribute the
local lesions to coccidia, which Giles says he finds frequently in the motions of
cases of kala-azar [ 3, p. 19 ] and which may infect the organs ; or to species of
amœba coli or cercomonas, which I found in many of the cases and which we
may easily conceivo to permeate the organs ; or to objects similar to those in the
liver and spleen of birds, lately described by MacCallum [ 21 ], which he thinks
may be some new protozoon, and which I too think I have recognised there ; or