The importance of the study of urology has of late been more fully
realized by Medical practitioners, and M. Demange in his thesis (_Thése
de Paris_, 1878) has undertaken to give a full account of the progress
of this branch of medical science, being also fortunate enough to be
able to enrich it by several new or very little known observations on
azoturia. The latter seem the most interesting part of his thesis; we
give them here briefly. The normal quantity of urea which must be
contained in the urine in the space of twenty-four hours is from
nineteen to fourteen grammes. If more or less is excreted, this is
caused either by some local or general affection. Some years ago,
Bouchard, in studying the causes of loss of flesh in patients suffering
from diabetes insipidus, discovered that a large number among them lost
an enormous quantity of urea. Having thoroughly examined their symptoms
he thought himself fully justified in describing azoturia as a special
disease, having peculiar clinical symptoms. The affection begins with a
sensation of ravenous hunger, polydipsia or profuse sweating. The thirst
is excessive, and the urine passed is generally in proportion with the
quantity of drink swallowed by the patient. Its density is from 1000 to
1002. In order to be able to calculate justly the amount of urea lost in
twenty-four hours, all the urine passed in twenty-four hours, all the
urine passed in this time must be kept and mixed. In some cases it has
reached the amount of eighty-seven grammes, a most enormous quantity,
which proves that nutrition is very much impaired. Senator Kien and M.
Bouchard have shown that what is called extractive matter is eliminated,
corresponding to urea in such cases, and that chlorates and phosphates
are ejected in a similar proportion. We must, therefore, not be
astonished if the patients present general symptoms which are analogous
to those of diabetic patients, with the exception of the visual troubles
of the latter. Both the crystalline lens and the retina remain intact,
and the sight is only influenced by the anæmic state of the brain, which
is caused by the dyscrasia, and which in certain cases produces a torpor
of the intellect verging on imbecility. As in cases of diabetes mellitus
and albuminuria, sometimes the quantity of urea decreases, and even
falls below the normal amount.
In order to be able to make an exact diagnosis, it is necessary to
examine carefully, both the urea and the other excreta, for several days
consecutively. As a rule, persons attacked by simple polyuria, or who
are suffering from interstitial nephritis, beginning with polyuria, do
not present the symptoms which we have enumerated.
Disturbances of the nervous symptom and alcoholism claim the first place
in the etiology of this affection, and indicate the treatment which has
to be adopted. It consists in administering drugs to calm the nervous
erethism (opium and valerian), and to put a stop to the excessive and
progressive impoverishment of the tissues (arsenic, a suitable diet,
etc.) Valerian has proved specially successful in different cases, even
effecting a complete cure. Besides these cases of azoturia, combined
with polydipsia, Bouchard thought that there was another form of the
same disease, in which there was no abnormal excretion of urine,
although the latter contained an excessive amount of urea. However, as
his observations in that respect are far from being satisfactory, and as
these are evidently cases of cachexia, the etiology of which is very
obscure, it will be wiser to leave them alone for the present. The
author then goes on to consider the much-debated question on the varying
amount of urea in glycosuria. In some patients suffering from the latter
affection, as much urea is eliminated as the general amount in azoturic
patients. It is true, however, that there may be something more than a
simple coincidence between these two affections, and several authors
have tried to link them together. Lécorché, who admits the hepatic
theory of the formation of urea, thinks that this is only the double
result of hyper-activity of the functions of the liver. Bouchard, on the
contrary, considers it as a true complication of the existing affection,
where troubles of nutrition are added to those resulting from
insufficient respiratory combustion. According to him, the difference
between melitæmia and azotæmia consists in the first resulting from the
accumulation of a product of secretion, while the second results from
the accumulation of a product of secretion. Azoturia is, therefore, as
we said, only a complication, an accessory element which must, however,
be considered as being a most important prognostic symptom. According to
the same author the abundance of sugar in diabetes is owing more to a
want of combustion than an exaggerated production of this substance in
the organisms. If this be the case, how can we explain the coincidence
of an abnormally low temperature with the production of an exaggerated
quantity of urea, such as has been observed in every case without
exception? This is the weak point of M. Bouchard’s theory, and it would
perhaps be better to refrain from giving a decided opinion on the
subject until it has been more thoroughly studied. In short, whenever
there is an excessive excretion of urea we may consider it as a symptom
of incipient cachexia, followed by loss of flesh. The most important
question, however, for the medical practitioner is the following: are
these two affections to be considered as belonging to two different
groups, but having been developed incidentally at the same time in the
same patient; or are they connected through a link which is still
unknown to us, thereby forming one affection or disease? If these
questions could be solved, there might be some hope of discovering some
rational mode of treatment, so as to prevent albuminuria from setting
in, in which case all is lost. In another chapter we find the
calculation of the amount of urea excreted in several chronic diseases,
such as obesity, syphilis and athrepsy. Here it is easy to make a
mistake, and still more so to err in trying to interpret the results
obtained, because here the nourishment taken by the patient plays an
important part, which is easily overlooked, e. g., in fleshy persons.
Azoturia may be produced either by excess of food, or by abstaining from
farinaceous food. The only way of ascertaining if the combustive
functions are really exaggerated in a patient would be to compare the
amount of chlorates contained in the secretions with the weight of the
patient. Since Brouardel published his paper, on what he termed the
uropoietic functions of the liver, several experiments have been made to
ascertain the amount of urea excreted in diseases of this organ. The
results have been very contradictory, but it is certain that large
quantities of urea have been found in the urine of patients whose liver
was completely degenerated.—_London Medical Record._