they chance to block up the common duct, and thereby prevent the bile
entering the intestinal canal. Hence, also, the reason {45} why
jaundice, as a result of gall-stones, is more frequently transient than
permanent. If it chances to become permanent, it sooner or later leads
to a fatal termination--usually within eighteen months after complete
obstruction. Lastly, it may be mentioned that, although gall-stones are
liable to form in almost every constitution, yet it is generally
considered that they are most frequent in persons of the tubercular,
cancerous, and gouty diathesis, either hereditary or acquired.
There are other substances besides gall-stones which, by their
accidental presence in the bile-ducts, may give rise to jaundice. Thus,
for example, foreign bodies, such as cherry-stones, have found their
way from the intestine into the bile-duct, and given rise to jaundice.
Intestinal worms have been observed to do the same thing, and recently
an interesting case of jaundice, occurring in a girl aged 16, who died
after a few weeks' illness, has been reported, which resulted from the
presence of hydatids in the ductus hepaticus, and ductus communis
choledochus.[17] Hydatids of the liver itself seldom give rise to
jaundice, their position being usually such as not to interfere with
the biliary function.
[Footnote 17: Dr. Dickinson has reported this case in the Pathological
Society's "Transactions," p. 104, vol. xiii. 1862.]
There are still other cases where we find {46} transient jaundice
arising from accidental obstruction of the bile-ducts; but in them,
instead of the closure of the ducts resulting from plugging from
within, it arises from the application of pressure from without. Thus,
for example, transient jaundice is met with as the result of closure of
the common bile-duct, by pressure exerted upon it by the pregnant
uterus, or by impacted fæces in the transverse colon. Certain permanent
abdominal tumours may also lead to the same result, but these will with
greater propriety be considered under the next head.
PERMANENT JAUNDICE FROM OBSTRUCTION.
In order to give as clear a view as possible of the pathology of
permanent jaundice from obstruction, it will be necessary for me to
give the history of a case of closure of the outlet of the common
bile-duct in consequence of organic disease--such, for example, as
cancer of the head of the pancreas. A case of this kind has the further
advantage of at the same time furnishing us with a typical example of
jaundice arising from the re-absorption of the secreted, but retained
bile.
When cancer of the head of the pancreas involves the orifice of the
common bile-duct, as the tumour grows, the duct slowly, and gradually
becomes impervious to the passage of bile into the {47} intestines,
until at length the flow is completely arrested. As this gradual
process of occlusion of the outlet goes on, the duct itself becomes
more and more distended by the retained bile, till it at length attains
an enormous size. The gall-bladder being equally prevented from
emptying itself, likewise becomes stretched and dilated, until it may
at last become not only palpable to the touch, but even apparent to the
eye through the abdominal walls. This was the case in the patient whose
liver, and occluded ducts are represented in Plate I.
The distention of the bile-ducts is not limited to those situated
external to the liver, but also affects those in the substance of the
organ; and to such an extent may this be the case, that, on making a
section of a liver that has long had its common duct obstructed, a
number of large excavations are observed all over its surface, which
excavations are nothing more than the open mouths of the transverse
sections of the dilated ducts. Such a state of matters is tolerably
well represented in the section of the liver in Plate I. Further, the
effect of this obstruction to the exit, and consequent accumulation of
the biliary secretion, is not confined to the mere distention of the
ducts, but causes various changes to occur in the parenchyma of the
liver itself. The first of these is an increase {48} in the size of the
organ, arising partly from the accumulation of the bile, and partly
from the congestion caused by the pressure exerted on the vessels by
the distended ducts. In the second place, gradually as the state of
matters here described progresses, the parenchyma of the organ becomes
itself affected, partly from the direct pressure exercised upon it, and
partly from the derangement of its nutrition, produced by the
interruption to the hepatic circulation; so that, after a time, the
enlarged liver slowly, and by degrees diminishes, until it at length
regains its natural size, thereby rendering, at this period of the
disease, the diagnosis of the case extremely difficult. This state of
matters is not, however, of long duration; for, in consequence of the
continued compression of the blood-vessels and parenchyma, the
nutrition of the liver is so disordered, as to lead to a gradual
shrinking of the entire substance, or, in other words, to a general
atrophy of the organ.
It is thus seen how in _permanent occlusion_ of the common gall-duct
the liver may be found _hypertrophied_ in the _first_, of _normal
dimensions_ in the _second_, and _atrophied_ in the _third_ and _last
stage_ of the disease.
In cases of the kind here described, it is not at all unlikely that the
enlargement of the liver in the earlier, as well as its atrophy in the
later {49} stages of obstruction, may be mistaken for the cause of the
jaundice, instead of the result of the arrest of the flow of bile, and
thereby lead to a grave error in treatment. The history of the case,
together with a knowledge of the above facts, will, however, tend to
facilitate the diagnosis. Thus, it must be ascertained:--
Firstly,--If the jaundice preceded the alteration in size of the organ.
Secondly,--If there is an absence of any history of hepatitis; and,
Thirdly,--If there is no evidence of any pulmonary or cardiac mischief
likely to lead to passive congestion of the hepatic tissue.
Even with a knowledge of all these facts, however, it often baffles the
skill, and acumen of the ablest physicians to discover the cause of
jaundice. Every now and then cases are met with, where the patient
tells us that the jaundice has gradually come on without any assignable
cause, and where, after the most careful examination of his history, as
well as of his physical condition, we fail to detect a clue to the
diagnosis. Cases of this kind are far from uncommon, and this is the
more to be regretted, seeing that unless we have a clear appreciation
of the cause, it is not only difficult, but even dangerous to treat the
symptom. The injudicious administration of {50} a remedy here, may
hasten the termination we most desire to retard. The truth of this
remark will, however, be better appreciated when I come to consider the
rationale of the treatment of jaundice. Meanwhile, it may be advisable
to point out a method capable of yielding most important information,
when all the ordinary means of diagnosis fail. I allude to the
chemistry of the excretions. Although the pathological chemistry of the
excretions is as yet in its infancy, it has already given the
scientific physician a key to the detection of several diseases, and I
trust to be able to show, that even in the obscure cases of jaundice
above alluded to, it not only gives us a clue to their cause, but
presents us with a guide to their treatment.
In jaundice arising from obstruction, the pipe-clay stools are, as in
the case of jaundice from suppression, entirely due to the absence of
bile from the intestinal canal. The yellowness of the skin is in like
manner caused by the accumulation of the bile pigment in the blood,
from whence it exudes, and stains the tissues; and, lastly, the
saffron-coloured urine results in a similar way from the elimination of
the pigment from the blood by the kidneys. Instead, however, of these
three conditions arising, as in the case of jaundice from suppression,
from the arrest of the biliary functions {51} allowing certain of the
constituents of the bile to accumulate in the circulation, they are, in
the first place, the result of the re-absorption of the secreted bile
from the distended ducts, and gall-bladder. So that while in jaundice
from suppression, only those biliary products which exist pre-formed in
the blood accumulate in the circulation, in cases of jaundice from
obstruction, the biliary products which are manufactured in the liver,
equally with those which are pre-formed in the blood, find their way
back into the circulation, to be from thence eliminated with the
excretions. If then, we could ascertain the presence or absence of
these products in the excretions, we should be enabled to distinguish
between jaundice resulting from suppression, and jaundice arising from
obstruction. Let us now see what the chemistry of the excretions
teaches us; and to begin, we shall take the intestinal excretion.
ANALYSIS OF THE INTESTINAL EXCRETION AS AN AID TO THE DIAGNOSIS OF
OBSCURE CASES OF JAUNDICE.
The intestinal excretion, in the natural state, consists, firstly,--of
those portions of our food which have resisted the action of the
digestive juices; secondly,--of the excess of the modified food
remaining unabsorbed; and, thirdly,--of the excess, {52} as well as of
the effete portions of the digestive secretions themselves.
Consequently, if from any cause the digestive secretions do not act
properly, the evacuation immediately becomes abnormal, and we can
discover by analysis which of the secretions is at fault. Thus, for
example, we know that the saliva acts upon the starchy matters of our
food, the gastric juice on the albuminous, the pancreatic on the fatty,
and that the biliary secretion so modifies the chyme as to allow of its
rapid absorption by the lacteal, and portal vessels. If then, from any
cause the elaboration, or excretion of any of these digestive juices be
interfered with, more of the particular kind or kinds of food on which
it acts, passes unchanged through the intestines. Thus, if the salivary
secretion be affected, an unusual amount of unmodified starch is found
in the stool. If the gastric juice is defective, more albumen than is
normal passes away unchanged, and so on with the others.
It is clear then, that an examination of the stools must afford us
important information regarding the presence, or absence of the normal
secretions. A simple inspection of the stool will sometimes at once
tell us whether or not bile is present. If it be present, the stool
varies from a pale yellow, to a dark olive-green hue, according to the
kind, and quantity of biliary colouring matter present, and {53} the
nature of the food. It must not be forgotten however, that unless care
be taken, the colour deducible from highly-coloured food may be
mistaken for an excess of bile. This remark is still more applicable to
medicines, for mercury, bismuth, iron, and some other mineral remedies,
give rise to dark evacuations so closely resembling bilious stools in
appearance, that the only way to distinguish them, is by chemical
analysis; when, the presence of the mineral, together with the absence
of the bile pigment, and the biliary acids (which are always to be
found in normal evacuations), will at once reveal the true nature of
the case. I have seen a mistake of this kind happen, and that too,
where a patient labouring under jaundice from obstruction, was thought
to be passing the usual amount of bile in his stools, when in reality
not a particle of bile pigment was present. The colour was in this case
entirely due to the food, and ferruginous remedies. Blood from the
stomach or bowels, is also apt to be mistaken for biliary matter, more
especially when acted on by the gastric juice, which has the property
of turning red blood brown. With these exceptions, the absence of bile
from the stool, is usually very easily ascertained. For if the patient
be taking no highly-coloured food, or any of the medicines above
indicated, the stools are of a {54} dirty pipe-clay colour. This is not
due to the presence of any new or foreign matter, but solely to the
absence of bile pigment. In these cases the evacuations, besides being
white, are usually of a most offensive odour, for, among other things,
bile checks intestinal putrefaction, and the development of offensive
gases.
In addition to the colour, and odour of the fæces, in cases of
jaundice, another important indication is to be found in the presence
of fat. The presence of fat in the stools was at one time looked upon
as evidence of pancreatic, at another time of hepatic disease; now,
however, experimental physiology has taught us, that it in some measure
depends upon both. For while, on the one hand, the pancreatic secretion
emulsions the fatty part of our diet, and thereby renders it capable of
absorption, recent researches, as has been already pointed out, have
established the fact that the biliary secretion also plays an important
part in the absorption of the oleaginous constituents of our food.
Bidder and Schmidt, as was before said, have shown that a dog, after
ligature of the gall-duct, absorbs less than half the average normal
quantity of fat; and by experiment it has been found that this arises
from the circumstance that bile emulsions only the acid fats, while
pancreatic juice transforms the neutral as well as the acid {55}
oleaginous matters. The presence of fat in the stools may be due,
therefore, partly to hepatic, partly to pancreatic derangement; and I
shall immediately point out how we can turn this fact to account in
diagnosis, and discover in cases of jaundice from obstruction, whether
the seat of the obstruction be at the outlet or in the course of the
duct.
EXAMINATION OF THE RENAL SECRETION.
The urine affords us important information in all cases of jaundice. In
fact, an examination of it alone would in many cases enable us to
discover the presence or absence of this affection.
_Diagnostic Value of the Colour of the Urine._
The urine of jaundice has invariably a peculiar tint, ranging from a
saffron-yellow to a dark olive-green, or almost black hue. It must not
be forgotten that the colour of normal urine varies with the degree of
concentration. Where little is passed, being of a high, where much is
passed, of a pale colour; the depth of colour depending on the degree
of dilution of the urohæmatine. Again, it must also be remembered that
there are many diseases, which change the colour of urine very
materially, some only deepening, others actually changing the tint.
Foods, and medicines also, {56} alter the colour of the renal
secretion. Rhubarb, and santonine give to it a saffron hue, arsenious
acid gas a black colour. Bearing in mind these facts, one would
hesitate before giving a decided opinion as to the presence or absence
of icterus from a mere inspection of the urine. For this reason, it is
generally recommended in cases of jaundice to pour a little of the
urine on a white plate, and watch the play of colours produced by
strong nitric acid. This method, however, is not always satisfactory,
for the play of colours depends on the different stages of oxidation
through which the pigment passes, and other animal pigments, besides
biliverdine, unfortunately act in a somewhat similar manner.
A very simple, and more convenient way of testing the pigment without
changing its physical characters, is to separate it in combination with
uric acid. This is readily done by simply acidulating the urine with a
few drops of hydrochloric acid, and setting it aside for twenty-four
hours to crystallize. The white uric acid in crystallizing takes up the
colouring matter, and assumes the hue of the pigment present in the
urine. I have thus obtained crystals of all the different hues from a
bright golden yellow tint through the intervening shades of red, brown,
blue, olive, to a dark, almost black colour. This experiment {57} has
another advantage, for if we take a measured quantity of urine, and
collect, dry, and weigh the uric acid obtained from it, we can readily
calculate the total quantity passed in the twenty-four hours, and
thereby assist in diagnosing the presence or absence of malignant
disease of the liver, as I shall afterwards have occasion to point out.
The urine of jaundice is generally described as being of a saffron
colour; but if I may be allowed to form an opinion from my own
observations, which are tolerably numerous, I should say that it, in
colour, much more frequently resembles old ale than anything else with
which I am acquainted. On standing, the colour changes very
considerably, in consequence of the pigment becoming slowly oxidized by
its exposure to the air. When there is a very great excess of bile
pigment present in the blood, the kidneys have some difficulty in
eliminating it. Occasionally even, it chokes up the renal capillaries,
and thereby complicates the jaundice by inducing secondary disease in
the kidney. In such cases the external surface of the kidney, after the
removal of the capsule, looks as if it had been sprinkled over with
ink. The black specks vary in size from the minutest visible point to
that of a pin-head. The accompanying chromo-lithograph (Plate II.)
represents a kidney in this condition. {58} It will also be observed
that it is studded over with a number of small abscesses; but whether
these resulted from the blocking-up of the capillaries just alluded to
or not, it is impossible to say. In the case in question no albumen was
detected in the urine during life, and it was only on careful analysis,
after the post-mortem had revealed the above state of matters, that a
small quantity was discovered; and even then, had not the experiment
been carefully performed, the presence of albumen might have been
overlooked.
[Illustration: Plate II. Kidney from a Case of Permanent Jaundice.]
_Diagnostic Value of the presence of the Bile-Acids in the Urine._
All acquainted with the recent literature of jaundice know how hard a
battle is being fought between two sets of observers in Germany,
regarding the presence of bile-acids in urine. One class, with Frerichs
and Städler at their head, believe that the biliary acids are
decomposed in the blood, and are consequently never to be detected in
the urine. The other class, headed by Kühne, state as positively that
they have detected these substances in the urine. Indeed, Kühne states
that by adopting Hoppe's method,[18] he never fails to {59} detect the
presence of the biliary acids in the urine of patients labouring under
icterus, as well as in the urine of dogs with the bile-duct ligatured.
When first studying this question, I was very much perplexed by these
contradictory statements, for neither the judgment, nor the power of
observation of either of the authorities could for a moment be called
in question; and on experimenting for myself, so unsatisfactory were
the results obtained, that I almost threw the question aside in
despair. On one occasion, however, I at length met with such
unmistakeable evidence of the presence of bile-acids in the urine, that
I could no longer doubt the fact of their existence, and was forced to
search for an explanation of the previous contradictory results.
Fortunately, it was not very long before a solution to the difficulty
was obtained, and, what was of still greater importance, led to the
observation that the contradictory results arose from a circumstance
which might be turned to account, as a means of differential diagnosis.
The discovery was, that in certain cases of jaundice not a trace of the
biliary acids is to be detected in the urine, although the {60} bile
pigment is present in abundance; while in certain other cases both
biliary acids, and bile pigment occur in notable quantity. What, then,
is the cause of this difference? Simply this. In jaundice from
suppression the liver does not secrete bile; consequently no bile-acids
being formed, none can enter the circulation, and they are therefore
not to be detected in the urine. In jaundice from obstruction, on the
other hand, bile is secreted, and absorbed into the blood; and the
bile-acids not being all transformed in the circulation, as Frerichs
supposed, are eliminated by the kidneys, and appear in the urine, where
they can be detected by Hoppe's method, or even, with proper
precautions, by simply adding sulphuric acid and sugar. Here, however,
some skill and experience are requisite, in order not to confound the
colour produced by the action of the reagents on other substances with
the fine purple produced by the biliary acids. As the majority of cases
of jaundice result from suppression of the hepatic function, and as
many of the cases of obstruction ultimately merge into the former, it
is easily understood how the existence of the biliary acids in the
urine has been so frequently denied. I have myself seen, in a case of
obstruction of the common duct, the biliary acids slowly and gradually
diminished in the urine, until they at length almost entirely {61}
disappeared as the case approached a fatal termination. Here the
disappearance of the biliary acids went on step for step with the
impairment of the secreting powers of the liver, in consequence of the
pressure exercised on its parenchyma by the retained bile.
[Footnote 18: Professor Hoppe tests for bile-acids in the following
manner:--The urine is boiled with an excess of milk of lime for about
half an hour, and filtered to free it from the precipitate thus formed.
The filtrate is evaporated to dryness, decomposed with hydrochloric
acid, washed with water, and then extracted with alcohol. The alcoholic
extract contains the bile-acids, which are recognised by Pettenkofer's
test.]
The readiest mode by which the biliary acids may be detected is the
following: To a couple of drachms of the suspected urine add a small
fragment of loaf-sugar, and afterwards pour slowly into the test-tube
about a drachm of strong sulphuric acid. This should be done so as not
to mix the two liquids. If biliary acids be present, there will be
observed at the line of contact of the acid, and urine--after standing
for a few minutes--a deep purple hue.[19] This result may be taken as a
sure indication that the jaundice is due to obstructed bile-ducts. On
the other hand, the absence of this phenomenon, and the occurrence of
merely a _brown_ instead of a _purple_ tint, although, in the earlier
stages of jaundice, equally indicative of suppression, is of course,
for the reasons already given, no indication of the cause of the
suppression. That must be gleaned from other circumstances.
[Footnote 19: The immediate formation of a reddish coloured line is due
to the acid setting free urohæmatine, the normal colouring matter of
the urine.]
It is seen that I have taken no notice of {62} Frerichs' theory
regarding the bile-acids being changed into bile pigment. I have done
so advisedly, feeling as I do, that when that observer investigates the
subject more fully, he will himself abandon such an untenable doctrine,
founded as it is, on an erroneous view regarding the nature of bile
pigment. The colour induced by sulphuric acid on the acids of the bile,
is as different in its chemical nature from animal pigment, as any two
substances can possibly be. Indeed, they have no bond of connection
whatever, except the mere tint. All animal pigments, whether they be
green, like bile-colouring matter, or red, like hæmatine, spring from
the same source, and contain iron. Besides this, the mere fact of an
increase of animal pigment being found in the urine after the
bile-acids have been injected into the circulation, to which Frerichs
attaches such importance, in reality proves nothing more, as Kühne
pointed out, than that an increased destruction of blood corpuscles has
taken place. I have found the urine of dogs loaded with dark colouring
matter after injecting chloroform, and other stimulants into their
portal veins, in order to establish artificial diabetes; and,
assuredly, in these cases the presence or absence of bile-acids in the
blood had nothing to do with the result.