portal vein, hepatic artery, and the hepatic veins. In the valley of
the Mississippi and its tributaries, where abscess of the liver is a
comparatively common disease, it has been found that in a large
proportion of the cases the initial stage is an affection of the
rectum--a form of dysentery properly entitled proctitis. So far as this
vast region is concerned, the intestinal disease which precedes abscess
of the liver, and stands in a causative relation to it, is an affection
of the mucous membrane from which the inferior hemorrhoidal veins
arise. This disease, although having a dysenteric form, is not ordinary
dysentery. The onset of the disease and its symptomatic expression are
those of a mild affection of the mucous membrane of the rectum--so
insignificant in some cases as to be recalled with difficulty. In
tropical countries abscess of the liver may be associated with
dysenteric ulcerations. This relation has been frequently observed, but
is far from constant. In Waring's[87] cases, which occurred in India,
31 per cent. of the fatal cases of hepatic abscess arose during the
course of acute or chronic dysentery. De Castro of Alexandria[88] finds
that dysentery is the most frequent cause of abscess in that region,
especially in the Greek hospital. Murchison[89] considers tropical
abscess of the liver as secondary to dysentery in a considerable
proportion of the cases, but by no means in all. In non-tropical
countries abscess of the liver is found to succeed to ulcerations of
the stomach, the intestines, the bile-ducts, etc. In the case of
ulceration of any part of the mucous membrane from which the portal
vein receives branches a morbific material may be conveyed to the
liver. This morbific material may be some unknown septic principle the
presence of which in the liver will excite suppurative inflammation; it
may consist of an embolus having septic power or a merely mechanical
irritant; it may be micrococci or some other living organisms, which,
arrested in the portal radicles, set up inflammatory foci, etc. There
are many examples of hepatic abscess connected with dysenteric
ulcerations of the intestine in which no embolus can be found.
Admitting the presence of the embolus originally, its disappearance is
readily understood by reference to the changes induced by suppuration.
Excepting these cases there must be many in which no embolus can be
found, because none existed; an unknown septic substance has excited
the suppurative inflammation. Emboli may be lodged in the liver from
thrombi formed in the peripheral distribution of the portal vein, or
from distant parts of the systemic circulation, as in bone diseases.
There has been no satisfactory explanation of the manner in which such
emboli pass the pulmonary capillaries to be lodged in the liver. At one
time there was supposed to be a special relation between injuries of
the bones of the head and hepatic abscess, but it is now known {1005}
that these cases are not more numerous than those due to osteo-myelitis
in any situation. Abscesses in the lungs are greatly more frequent than
in the liver in cases of this kind. According to Waldeyer,[90] whilst
in two-thirds of the cases of death from surgical diseases and injuries
there were abscesses in the lungs, in only 6 per cent. were there
abscesses of the liver. It is evident that the emboli entering the
systemic circulation are usually arrested in the pulmonary capillaries.
Klebs maintains that such emboli consist of parasitic organisms.
[Footnote 87: _On Abscess of the Liver_, _supra_.]
[Footnote 88: _Des Abcès du Foie des Pays chauds, et de leur Traitement
chirurgical_, par le Dr. S. V. Castro (d'Alexandrie d'Egypte).]
[Footnote 89: _Clinical Lectures_, _loc. cit._, p. 178.]
[Footnote 90: _Virchow's Archiv für path. Anat., etc._, Band xl. pp.
380, 408.]
Dilatation and ulceration of the bile-ducts were the principal causes
of hepatic abscess, as ascertained by Von Baerensprung, in the Berlin
Pathological Institute. Duodenal catarrh involving the orifice of the
common duct, catarrh of the biliary passages leading to obstruction,
and plugging with a gall-stone have resulted in abscess, the initial
lesion being probably rupture of one or more of the finer tubes or
inflammation leading to suppuration.[91]
[Footnote 91: Grainger Stewart, _The Edinburgh Medical Journal_,
January, 1873.]
Finally, a considerable proportion of cases of hepatic abscess arise
under unknown conditions. In such cases, however, it is usually found
that there has been more or less indulgence in alcoholic drinks, or the
liver has been taxed by excesses in the use of rich foods and
condiments, or exposure to extreme degrees of temperature has occurred.
In the interior valley of this continent, where hepatic abscess is
comparatively common, the causes are to be found in malarial
influences, in alcoholic indulgence, in dysenteric attacks the product
of climatic variations and improper alimentation, and in the formation
and arrest in transitu of hepatic calculi also the result of
long-continued gastro-duodenal and biliary catarrh.
PATHOLOGICAL ANATOMY.--Great differences of opinion have been expressed
as to the initial lesions in hepatic abscess. It is probable, however,
that these differences are due to the character of the abscess. Some
have their origin in the hepatic cells, others in the connective
tissue, and others still in the vessels. There may be a number of
points at which the suppurative process begins, or it may be limited to
one. Virchow[92] describes the initial lesion as beginning in the
cells, which first become coarsely granular, then opaque, and finally
soften, and pus appears. Klebs, who maintains the constant agency of
septic micrococci, affirms that the changes in the cells are due to
compression exerted by the mass of these organisms distending the
neighboring vessels, and then suppuration begins on the portal side of
the lobules. Liebermeister originally held that the initial lesion is
in the connective tissue; and this view is also supported by Köster,
who brings to bear experimental data. In the walls of the vessels of
the connective tissue and about them, between the hepatic cells, great
numbers of lymphoid cells accumulate. The intercellular spaces are also
distended with plasma and round cells, and in the vicinity of the
central vein the swollen hepatic cells are pressed together; soon
pus-corpuscles appear, and the proper anatomical elements are broken up
into a diffluent mass composed of fat-granules, pus-corpuscles, and
disintegrating hepatic cells.
[Footnote 92: _Archiv für path. Anat., etc._, Band iv. p. 314.]
When suppurative hepatitis arises from an embolus, or emboli, the
{1006} first step is the change in the appearance of the acini, which
are enlarged and grow softer by disintegration of their cells; then at
the centre a yellowish spot appears, and is made up of the detritus,
granules of fat, and pus. Surrounding such softening portions of the
hepatic tissue is a zone of congestion. When the morbid processes are
excited by emboli, there will be as many centres of pus-formation as
there are particles distributed by the vessels--from two or three to
fifty or more. They may be uniformly distributed through the organ or
be collected in one part. Emboli conveyed by the portal vein will be
arranged with a certain regularity and through the substance of the
liver, whilst those coming from some part of the systemic circulation
tend to form at the periphery under the capsule. Small abscesses in
close proximity unite ultimately by the softening and disintegration of
the intervening tissue.
In the so-called tropical abscess, which is the variety so frequently
met with in the interior of this country, the mode of development is
different from the embolic, above described. Owing to the deposit of
some morbific matter whose nature is now unknown, the vessels dilate
and hyperæmia of the part to become the seat of suppuration ensues. The
cells become cloudy, granular, and opaque from the deposit of an
albuminous matter in them. Within the area of congestion a yellowish
spot soon appears, surrounded by a translucent, pale-gray ring, and
here suppuration begins; the neighboring cells disintegrate and a
purulent collection is formed, which enlarges by the destruction in
succession of the adjacent portions of hepatic tissue. Whilst this
process is going on there is a border of deep congestion about the
abscess, fading off gradually into the normal tint of the hepatic
parenchyma; the walls of the abscess are rough and irregular from
projections of tissue just beginning to disintegrate, and the pus
burrows in various directions more or less deeply into the softening
parts. The size to which such purulent collections attain is largely
determined by the condition of the liver as a whole. If the organ
attacked is healthy otherwise and the general health is not
deteriorated, the area of the abscess may be limited by a well-defined
membrane and continue inactive for a long time. This limiting membrane
is of inflammatory origin, developed from the connective tissue, and
varies in thickness from a mere line to several. It was formerly called
a pyogenic membrane, because the pus discharged was supposed to be
formed by it. When such a limiting inflammation cannot take place, the
abscess continually enlarges by the softening and destruction of the
adjacent hepatic tissue, and may finally attain to enormous
proportions. The embolic abscesses vary in size from that of a pea to
that of an orange. The so-called tropical abscesses are usually
single--in three-fourths of the cases, according to Rouis;[93] in 62.1
per cent., according to Waring.[94] Of the fatal cases collected by the
latter author, 285 in number, a single abscess existed in 177, and
multiple abscesses in 108. In 11 per cent. there were two abscesses; in
3.6 per cent., three; and in 5.6 per cent. there were four abscesses.
As regards the part of the liver in which abscess occurs, the
statistics show a great preponderance in favor of the right lobe. In
Waring's collection of 300 cases the right lobe was the {1007} seat of
the abscess in 163, or 67.3 per cent.; the left lobe was affected in
16, or 6.6 per cent.; and both lobes in 35, or 14.4 per cent. The
preponderance of cases affecting the right lobe is the more striking
when it is understood that, other parts being invaded, the right is
included with them in the morbid process. In my own cases the right
lobe was the seat of the abscess in 70 per cent.
[Footnote 93: _Recherches sur les Suppurations endémiques du Foie_,
_loc. cit._, p. 146.]
[Footnote 94: _An Inquiry into the Statistics and Pathology, etc.
connected with Abscess of the Liver_, _loc. cit._, p. 125.]
The contents of the abscesses are affected in character by the form of
the disease, whether embolic or tropical, by its rate of development,
by the condition of the hepatic parenchyma, by the formation of a
limiting membrane, etc. In the more chronic cases, surrounded by a
dense membrane, the pus is usually laudable or dry and cheesy; in the
acute embolic cases the pus is dark brown, ichorous or grumous, and
contains a good deal of detritus of the hepatic parenchyma; and in the
tropical cases it is of a sanguinolent, dark color, or more frequently
of a grayish purulent fluid; and in the acute forms contains much
broken-down tissue, whilst in the chronic cases, in direct ratio to
their duration, the pus approaches the laudable character. The source
of an abscess discharging from the neighborhood of the liver may be
ascertained by a microscopical examination and the discovery of the
hepatic elements (the cells) in the fluid. Bile may also be present in
the pus.
The abscesses not confined by a limiting membrane constantly enlarge by
the softening and disintegration of the adjacent liver substance, and
those enclosed or encysted after a period of quiescence of variable
duration begin active efforts to establish communication outwardly. The
point to which a purulent collection in the liver tends becomes an
important element in diagnosis and in treatment. As the abscess
approaches the surface of the liver the capsule inflames, and if
adhesions are not formed more or less sloughing occurs, and the
contents are discharged into the abdominal cavity. Adhesions may form
to the parietes, an external swelling appear, and after a time
discharge take place in the right hypochondrium at some point. Pus may
escape at the umbilicus, in the right inguinal region, posteriorly at
the sacro-iliac junction, and in other situations. Adhesions may form
to the stomach, duodenum, the ascending vena cava, to the diaphragm
opening the thoracic cavity, the pericardium, or the mediastinum; and
the accumulated pus may thus find a vent. According to Waring,[95] the
termination of hepatic abscess is as follows: Of 300 cases, 169, or
56.3 per cent., remained intact--that is, had not advanced beyond the
liver; 48 were evacuated by operation, or 16 per cent.; 14, or 4.6 per
cent., entered the thoracic cavity; 28, or 9.3 per cent., opened into
the right lung; 15, or 5 per cent., entered the abdominal cavity; 7, or
2.3 per cent., opened into the colon; 1 entered the stomach; 3 entered
the hepatic vein near the vena cava; 1 communicated with the hepatic
ducts, 2 with the right kidney, etc. The termination of 162 fatal
cases, according to Rouis,[96] was as follows: 125 proved fatal in
consequence of the extent of the abscess or of the severity of the
accompanying dysentery; 3 terminated by gangrene of the walls of the
abscess; 3 by peritonitis; 12 by opening of the abscess; 2 by rupture
of adhesions; 11 by opening of the abscess into the pleura; 2 by
intercurrent and 3 by secondary pneumonia. Notwithstanding the
differences {1008} in the mode of expressing the conditions, the
general results are the same.
[Footnote 95: _An Inquiry into the Statistics and Pathology, etc. of
Abscess in the Liver_, _loc. cit._]
[Footnote 96: _Recherches sur les Suppurations endémiques, etc._, p.
149.]
An abscess of the liver having discharged in a favorable way, healing
may take place. There may be such an extent of injury--the whole
secreting structure of the liver being destroyed--that repair is beyond
the power of the organism. The best results are attained when discharge
occurs by the most direct route externally; the next, by way of the
right lung; the third, by the stomach or intestine. Repair cannot be
hoped for when a large part of the normal hepatic structure is
destroyed. When the pus escapes the walls of the abscess approximate,
and union takes place by connective tissue, leaving a radiated or a
merely linear cicatrix to mark the site of the purulent collection. So
perfectly does repair take place in suitable subjects that no trace of
the lesion may remain.
Those portions of the liver outside the borders of the abscess, and
beyond the vascular derangements produced by it, may be entirely
healthy. In the cases terminating in recovery the portion of the liver
unaffected by abscess continues to functionate normally. More or less
of the liver may be destroyed; hence it follows that recovery may be
partial. According to the damage done to the proper secreting structure
of the organ will the recovery be partial, limited, or complete.
SYMPTOMS.--The existence of an abscess of the liver is determined by
systemic or general and by local symptoms, and they may be acute or
chronic.
Systemic.--In acute cases the beginning of mischief may be announced by
a rigor, but more frequently this indicates the onset of suppuration,
and is one of the phenomena of the chronic form. As the disease occurs
in this country, a chill takes place suddenly in a case which presents
the usual symptoms of proctitis (dysentery) during the course of this
affection or soon after its apparent cure; then a febrile movement
occurs, and subsequently an irregular intermittent, the rise of
temperature being preceded by rigors or mere transient chilliness. With
these febrile symptoms there may be associated uneasiness in the right
hypochondrium, acute pain, or a feeling of weight and pressure, with
jaundice, etc. The fever is septicæmic, intermittent, or remittent if
it have any special type. In the septicæmic form the rigors are severe,
occur irregularly, sometimes daily, sometimes twice a day, and at
intervals of two or three days or longer; the fever rises to a high
point--104°, 105°, or higher--and the sweats are profuse. In the
intermittent form the fever usually has the quotidian type; some slight
chilliness is experienced in the early morning as a rule, and the
exacerbation occurs in the afternoon and evening, the sweating being
slight toward the morning. More frequently, in the writer's
observation, the type of fever has been remittent, with periodical, but
not regularly so, exacerbations. In such cases the morning temperature
has been at 99° or 100°, and the evening 102° or 103°. Such a range of
temperature may be present during three or four weeks or even longer,
the abscess gradually making its way outwardly. Conclusions may be
drawn from the behavior of the febrile movement as to the character of
the local affection, with the limitations imposed by the necessary
uncertainty of the data. If the chills are decided rigors, the fever
{1009} high, and the sweats profuse, either pyæmic abscesses or large
tropical abscesses implicating neighboring organs exist. The simple
intermittent, especially the remittent, form of fever suggests
abscesses of medium size making their way outwardly, with only partial
injury to the parts traversed. In a certain portion of the cases the
type of fever changes when a large accumulation of pus takes place;
after several weeks of a mild remittent the fever becomes irregularly
intermittent with rigors, strong exacerbations, and profuse sweats. In
protracted cases the fever assumes the typhoid aspect; there is
profound adynamia, dry tongue, sordes, diarrhoea, and the usual
symptoms of this state. When the secreting structure of the liver is
destroyed to a large extent, the condition of acholia is superadded to
the typhoid state.
The pulse is irritable and quick from the beginning of the symptoms. In
a few instances a slow pulse, such as occurs in jaundice, has been
observed, but generally the number of cardiac contractions is in a
direct ratio with the body temperature. When typhoid symptoms supervene
in advanced cases the pulse becomes weak and dicrotic.
Not every case presents the symptom sweating. The chronic cases with
mild remittent fever have little more than slight moisture of the
surface, whilst the acute and pyæmic cases are characterized by profuse
sweats. If to an irregular febrile movement, preceded by chills and
followed by sweats, there is added the tendency to sweat on all
occasions--on slight exertion, on sleeping, under any
excitement--suppuration may be suspected.
General malaise, a sense of fatigue and exhaustion, and progressive
decline in flesh and strength occur. It is remarkable, however, how
some obese subjects preserve their roundness and apparent fulness of
habit. Usually, however, emaciation advances pari passu with the
progress of the suppuration. The more acute the symptoms, the more
rapid the wasting. When an encysted abscess develops in the course of a
chronic dysentery, there may be no appreciable change in the condition
of the patient properly attributable to the additional lesion. The loss
of appetite, the frequent vomiting, and often the dysenteric troubles,
contribute materially to the exhaustion and the wasting of the tissues.
The stomachal derangements may be present with the initial symptoms,
but they are usually more pronounced when the abscess attains to
considerable size.
A peculiar tint of the skin, especially of the face, is observed in
those cases without jaundice. There is an earthy or sallow hue, which
to the practised eye signifies suppuration. Jaundice is present in a
less proportion of cases. In 13 of Waring's cases the skin is said to
be sallow. In Rouis's collection icterus was present in 17 per cent.,
or 26 times in 155 patients. According to Waring, jaundice is rarely
present. In the 12 cases in my own hands actual jaundice was not
present in one, but 9 had an earthy hue or presented some yellowness of
the conjunctiva. In fact, jaundice does not have the importance as a
symptom which might, a priori, have been expected.
The mental condition of these subjects is that of depression. They
sleep poorly, are disturbed by vivid dreams of a horrifying character,
and the nocturnal sweats increase the tendency to wakefulness.
Hypochondria, or at least marked symptoms of mental depression, as
{1010} Hammond[97] has shown, are present in many cases. So frequent,
indeed, seems to be the association of a depressed mental state with
hepatic abscess that in every case of the former the liver should be
carefully explored. Hammond goes so far as to say that in every case of
hypochondriasis puncture of the liver with the aspirator needle should
be practised when any symptom, however indefinite, indicates the
existence of an abscess. Besides the condition of hypochondriasis in
many cases, there may be stupor, hebetude of mind, confusion due to
acholia, cholæmia (Flint's cholesteræmia), when a large part of the
liver structure is destroyed.
[Footnote 97: _Neurological Contributions_, vol. i. No. 3, p. 68: "On
Obscure Abscesses of the Liver, their association with Hypochondria and
other Forms of Mental Derangement, and their Treatment."]
Sweating has already been referred to as a phenomenon connected with
the febrile movement. It is necessary to state further that this may
vary in amount from a mere moisture of the surface connected with
sleep, or it may be a profuse diaphoresis with which the febrile
paroxysm terminates. As a systemic symptom, sweating is strongly
suggestive of suppuration, and may therefore be extremely significant,
in this connection, of suppuration in the liver. According to Waring,
of 75 cases specifically interrogated on this point, 72 presented this
symptom. Rouis refers (p. 123) to it as very constantly present, coming
on chiefly at night--sometimes generally over the body, sometimes
limited to the head, and always accompanied by an accelerated pulse.
The urine in cases of hepatic abscess varies; it is never normal. There
may be merely an excess of urates--a symptom common enough in all
febrile affections and in suppuration. It is usually high-colored,
deficient in urea, and contains leucin and tyrosin, and not often
bile-pigment, except when jaundice is present, which, as we have seen,
is rather uncommon.
It should be borne in mind that whilst the above-described mental and
cerebral and other symptoms are often present, they are by no means
invariably so. There are cases, usually of encysted abscess, in which
no functional disturbance of any kind exists. But the systemic symptoms
are by no means so important as the local. To these we must now direct
attention.