# Tropical Diseases/Chapter 34

CHAPTER XXXIV
ABSCESS OF THE LIVER
Definition.— A form of suppuration in the liver, occurring especially in warm climates, principally in male Europeans and in association with amœbic dysentery.
Geographical distribution.— Abscess of the liver, of the type known as tropical abscess, is, for the most part, a disease of warm climates. Usually a sequel, or, it may be, a concomitant of amœbic dysentery, it is rare or altogether absent in countries where this type of dysentery is also rare or absent. Its geographical distribution, therefore, is in the main regulated by that of amœbic dysentery. It has to be noted, however, that liver abscess is not a sequel or concomitant of the dysentery of all countries and at all times. Thus it is rare as an indigenous disease in temperate climates, even in those temperate climates in which dysentery is at times common enough. Again, in tropical climates the dysentery and liver abscess curves do not everywhere and at all times maintain a constant and definite relation to each other; for, even in hot countries, the dysentery of some places is more apt to be followed by liver abscess than is the dysentery of other places; and, even as regards dysentery in the same place, some epidemics are more apt to be associated with liver abscess than are others. Manifestly this apparent anomaly depends on the type of dysentery. On the whole, it may be laid down as a fairly general law that in the tropics and sub- tropics the liver abscess curve follows, in the main, the dysentery curve; and that the geographical range of liver abscess in these climates is the same as that of dysentery.
In Great Britain the liver abscesses met with occur most frequently in individuals who manifestly ​had contracted the disease in the tropics. As a disease of indigenous origin, notwithstanding the considerable amount of dysentery in lunatic asylums and similar large public institutions in Great Britain, it is distinctly rare, though not so uncommon as is usually supposed. Of course this remark does not apply to those suppurations which are connected with ordinary pyæmia, with gall-stones, hydatids, pylephlebitis, and the like; it applies only to dysenteric and, possibly, if there be such a disease, to idiopathic abscess. In northern and central Europe it is much the same in this respect as in Britain. The disease is more frequent in southern Europe in Italy, Greece, the Balkan peninsula, and south Russia; it is said to be particularly common in Roumania. In eastern Asia, even outside the tropical belt, it is far from rare: thus, it is not uncommon in Japan, and it is a very notable feature of the morbidity of Shanghai and the coast of south China. In north and tropical Africa it is common enough; indeed, some of the best modern studies of the disease have been made in Egypt and in the Algerian province of Oran. In the western hemisphere there is a corresponding distribution; fairly common in the tropics, it becomes progressively rarer as we proceed north and south. It is apparently less common in the West Indies than in India and the East generally. In the southern hemisphere, although the Cape and Transvaal and the cooler parts of Australia seem to enjoy a practical immunity, the European in the Northern Territory of Australia and in the neighbouring island of New Caledonia is subject to this disease.
The apparent caprice in the geographical distribution of liver abscess is probably, in great part, explained by what has already been stated with regard to the distribution of amœbic dysentery, and to the effects of high atmospheric temperature and tropical habits on the European liver, together with the circumstance, as will be mentioned in the sequel, that the amoeba is an important, if not a principal, element in the production of tropical liver abscess. ​Evidence tends to show that liver abscess is the sequel or associate of amœbic dysentery— a disease practically confined to warm climates ; not of bacillary dysentery, the usual form of dysentery occurring in temperate and some warm climates.
Etiology,— Relation to dysentery.— There can be no question as to the existence of an intimate relationship between dysentery and liver abscess. Numerous and well-authenticated statistics, as well as everyday experience, attest this. In 3,680 dysentery autopsies made in various tropical countries, and collated by Woodward, 779 (21 per cent.) revealed abscesses of the liver. To quote recent Indian experience: According to the Annual Report of the Sanitary Commissioner with the Government of India for 1894, out of 465 European soldiers who died from dysentery in India during the period 1888-94, 161 (35 per cent.) had, in addition to dysenteric lesions, abscess of the liver. Conversely, in Egypt, Kartulis, in an experience of over 500 cases of liver abscess, elicited a history of dysentery in from 55 to 60 per cent.; Zancarol, also in Egypt, in 444 cases, elicited a similar history in 59 per cent.; and Edwards and Waterman, in 699 collated cases, elicited a like history in 72.1 per cent. During the period 1870-95, of 45 cases of liver abscess treated at the Seamen's Hospital, 'Greenwich, and collated by Mr. Johnson Smith, postmortem evidence or a distinct history of dysentery was obtained in 38 (84.4 per cent.).
These figures are conclusive as to the existence of an intimate relationship between dysentery and liver abscess. There is good reason, however, for believing that, while they represent the truth, they do not represent the whole truth, and that the association is even more frequent than they indicate. As has been pointed out by McLeod and others, the occurrence of antecedent dysentery in cases of liver abscess is very often overlooked; for, without a postmortem examination, it may be impossible to pronounce definitely on this point in every instance. It is also well known that extensive dysenteric ulceration may be present and yet give rise to no active ​subjective symptoms whatever. Moreover, many patients suffering from liver abscess forget, or fail to mention, the occurrence of a previous dysenteric attack, or may mislead the physician by describing such an attack as " diarrhœa." Further, at postmortem examinations, dysenteric lesions of a superficial and apparently trifling character are often either not sought for, or are overlooked, or have disappeared; moreover, it is now well ascertained that the amœbæ may be present without producing definite intestinal lesions. Consequently, although the evidence of antecedent dysentery may not be forthcoming in a proportion of cases of liver abscess, it must not be concluded that in these cases there has been no dysentery or amœbic infection.
In a masterly paper McLeod, after a very careful and critical analysis of certain figures bearing on this subject, concludes that dysentery is a factor in nearly every case of tropical liver abscess. In 40 cases of the disease observed in Shanghai he had positive evidence of dysentery in all except one; and even in this case, as recovery ensued, there was no certainty that dysenteric lesions had not been present. Perhaps McLeod's conclusions are somewhat too sweeping I confess, however, that they are, in the main, in harmony with my own experience. Doubtless they apply to liver abscess as met with in Shanghai and, probably, in many other places. It "is just possible, however, that what holds good for one place may not hold good for all places, and that Bombay, for example, may differ in this respect from Shanghai. In the Sanitary Commissioner's Report, above referred to, it is stated that in 2 (3 per cent.) instances only, out of 74 cases of liver abscess occurring in the Bombay Presidency in the period 1888-94, were there dysenteric associations. It is difficult to believe that, did it always exist, so important and evident a circumstance as dysentery had been overlooked in 72 out of 74 cases. It is equally difficult to believe that the liver abscess of Bombay is associated with dysentery in only 3 per cent, of cases, whilst, according to the same authority, in the whole of ​India it is certainly so associated in at least 30 per cent, of the total cases. Manifestly, the statistical aspect of this important question requires re-study in the light of more careful clinical and post-mortem observation.
Another important point yet to be definitely settled is the exact relationship in point of time of the dysentery to the liver abscess. In the great majority of cases the dysentery antedates the abscess. But many clinicians have held that in some instances the relationship is reversed; that in others the two diseases are from the commencement concurrent; whilst in others, again, hepatitis, presumably of a kind which may eventuate in abscess, alternates with active dysenteric symptoms. If the abscess antedate the dysentery, then the dysentery cannot be the cause of the abscess. On these grounds some pathologists have regarded liver abscess and dysentery as but different expressions of one morbid condition; reacting to some extent on each other, but not directly related the one to the other as cause and effect. Here, again, the latency as regards symptoms of some dysenteries has to be discounted in attempting to settle the question on clinical grounds only. All these discrepancies and differences of opinion have to be re-studied in the light of the acknowledged relationship of the amoeba to dysentery and to liver abscess.
Race, sex, and climate.— Besides its relationship to dysentery, there are several well-ascertained facts to be reckoned with before we can arrive at sound views on the subject of the etiology of liver abscess.
1. Though common in Europeans in the tropics, liver abscess is rare among the natives. Thus, in the native army of India the proportion of deaths from liver abscess to the total mortality in 1894 was only 0.6 per cent., whereas in the European army it was 7.4 per cent. Man for man, the relative liability of the European soldier and the native soldier was as 95.2 to 4.8.
2. This disproportion is in spite of the fact that the native is more liable to dysentery than the European. Thus, in 1894, in the Indian army the ​admission -rate among the native troops for dysentery was 43.8 per thousand, whereas in the European troops it was only 28.6; and in every hundred deaths in the native army 4.7 were from dysentery, against only 3.8 in the European army.*
3. European women in the tropics, though quite as subject to dysentery as European men, rarely suffer from liver abscess; children hardly ever.
4. The rarity of liver abscess in temperate climates.
Predisposing conditions.— The foregoing considerations seem to indicate that for the production of liver abscess at least two things are necessary— a predisposing cause and an exciting cause. Dysentery is certainly not always and alone both the exciting and the predisposing cause. Were this so, native soldiers and European women and children in India would suffer as frequently from liver abscess as do European males there. Some additional factor evidently complicates the problem.
As liver abscess is developed principally in tropical climates and in European visitors there, and much more rarely in the native, it would seem that tropical conditions in those unaccustomed to them are in some way bound up with this predisposing element; and as liver abscess is rare in European women and children, it would seem that these conditions are in some way specially operative on European men. We have grounds, therefore, for concluding that, in addition to general tropical conditions, it must be the greater amount of exposure to which men, as compared with women and children, are subjected in the course of their business and amusements; or some other condition, especially that one which is relatively more common in men than in women and children, and ​which is a universally recognized cause of hepatic disturbance— over-indulgence in stimulating food and alcoholic drinks— that constitutes this predisposing cause. Intemperate habits and exposure, doubtless, lead to a special liability in men to a hyperæmia and congestion of the liver tissue by which its resistance to pathological influences is impaired. In these circumstances, pathological influences which in the healthier condition of the organ— such as we assume to exist more generally in natives and in European women and children— would have been successfully overcome, gain the upper hand and lead to suppurative disintegration of the organ. In support of this view we have the statement of Waring that 65 per cent, of liver abscesses observed by him were in alcoholics ; and it is also said that when the native takes to European habits in the matter of eating and, especially, of drinking, his liability to liver abscess is greatly and proportionately increased.
I conclude, therefore, that in the vast majority of instances the exciting cause of liver abscess is amœbic dysentery: the predisposing cause, hyperæmic, congestive, or degenerative conditions incidental to tropical life, supplemented by such things as exposure and unphysiological habits in eating and drinking.
Supplementary causes.— It is conceivable that in a highly predisposed liver exciting causes other than dysentery, such as a blow or sudden aggravation of chronic congestion by chill or excess, may suffice at times to determine suppuration. Liver abscess is most prone to develop at the commencement of the cold season. Further, one can conceive that in a hyperæmic liver struggling to resist dysenteric suppurative influences some third condition, such as the blow, chill, or surfeit referred to, may contribute to or determine the formation of abscess which, in its absence, might have been averted.
Briefly stated, the causes of liver abscess are, first, predisposing— hyperæmic and degenerative conditions of the liver; second, exciting— amœbic dysentery, or dysentery combined with chill, dietetic excess, or traumatism. ​Influence of age and length of residence.— Liver abscess may occur at any age after childhood, but is most common between 20 and 40. It is most prone to show itself during the earlier years of residence in the tropics (40 per cent, in the first three years), although the older resident is by no means exempt.
Influence of malaria.— Malaria, by causing frequent attacks of hepatic congestion and by lowering the general vitality, may have some predisposing influence; but, as already pointed out, malarial hepatitis is essentially of a plastic and not of a suppurative nature. It is a common mistake to suppose that malaria causes the suppurative liver disease of the tropics; the two concur geographically to a certain extent, but are in no way etiologically identical.
Morbid anatomy.— It may be inferred from the symptoms that in the early stages of suppurative hepatitis there is general congestion and enlargement of the liver; in some instances this condition may be more or less confined to one lobe or even part of a lobe. Later, as we know more especially from observations in cases that have died from the attendant dysentery, one or more greyish, ill-defined, anæmic, circular patches, ½-1 in. or there-abouts in diameter, in which the lobular structure of the gland cannot be made out, are formed. These grey spots are very evident on section of the organ. A drop or two of a reddish, gummy pus may be expressed from the necrotic patches— for such they are. Still later, the centres of the patches liquefy, and distinct but ragged abscess cavities are formed. An abscess thus commenced extends partly by molecular breaking down; partly by more massive necrosis of portions of its wall; partly by the formation of additional foci of softening in the neighbourhood and subsequent breaking down of the intervening septa. The walls of such an abscess have a ragged and rotten appearance. Spherical on the whole, there may be one or more diverticula extending from the main cavity; or contiguous abscesses may break into each other and communicate by a sinus. Occasionally a thickened blood-vessel is met with, stretching across ​the cavity. Though the pus and detritus lying on the abscess wall are viscid and adhesive, there is no notable exudation of lymph either lining the cavity or in the still living liver tissue beyond. There is a peripheral zone of hyperæmia; beyond this zone the gland may appear normal or simply congested.
Number, size, and situation of abscesses.— Liver abscess may be single or multiple. If multiple, there may be two, three, or many abscesses. Zancarol's statistics, applying to 562 cases, give the proportion of single to multiple abscess cases as three of the former to two of the latter.
When single the abscess sometimes attains a great size. Frequently it is as large as a coco-nut or even larger; it has happened that the entire liver, with the exception of a narrow zone of hepatic tissue, has been converted into a huge abscess sac. When multiple the individual abscesses are generally smaller, ranging in size from a filbert to an orange.
As might be expected from considerations of the relative size of the parts, single abscess is much more common in the right than in the left and smaller lobes. What might be termed the seat of election is the upper part of the right lobe. Roux gives the proportions in 639 cases as 70-85 per cent, right lobe, 3 per cent, left lobe, and 0.3 per cent, lobus Spigelii.
Adhesions to surrounding organs are frequently, though not invariably, formed as the abscess approaches the surface of the liver. In this way the danger of intraperitoneal extravasation is usually averted.
Pulmonary inflammation and abscess from escape of liver pus into the lungs are sometimes discovered post mortem. Generally the pulmonary abscess communicates with the mother abscess in the liver by a small opening in the diaphragm, the pleural sac being shut off by adhesions .
Liver pus.— The naked-eye appearance of liver pus is peculiar. When newly evacuated it is usually chocolate - coloured and streaked with, or mixed with, larger or smaller clots or streaks of blood, ​and here and there with streaks of a clear mucoid or yellowish material. It is so thick and viscid that it will hardly soak into the dressings; it lies on the surface of the gauze like treacle on bread, spreading out between the skin and the dressing, and finding its way past the edge of the latter rather than penetrating it. When quite fresh, here and there little islands of what may be described as laudable pus may be made out. in the brown mass. Sometimes it contains considerable pieces of necrotic tissue. Occasionally, from admixture of bile, the abscess contents are green-tinged. Liver purulage has always a peculiar mawkish odour; it is rarely offensive unless the abscess lie near the colon, in which case it may have a fæcal odour. Under the microscope many blood corpuscles are discoverable, besides much broken-down liver tissue, large granular pigmented spherical cells, leucocytes, debris, oil globules, hæmatoidin crystals, and, occasionally, Charcot-Leyden crystals and amœbæ; rarely the ordinary pyogenic bacteria.
Amœbœ, and pyogenic organisms.— According to my experience of tropical abscess of the liver seen in England, amoebae can be detected in considerably over half the cases. This agrees with Kartulis's experience in Egypt, and that of others elsewhere. Rogers concludes from a careful examination of scrapings from the walls of a large number of liver abscesses in Calcutta that the amoeba is always present. I have observed in a good many instances in which I have failed to detect the amœba in the aspirated liver pus, or in the pus which escaped at the time of operation, that the parasite appeared, often in great profusion, four or five days later in the discharge from the drainage-tube. I have seen them in these circumstances in strings of eight or ten; the string-like arrangement suggesting that they had developed in some tube, such as a blood- or bile- vessel. The amœbæ may persist in the discharge until the abscess has healed. It is justifiable to infer from the absence of amœbæ from the pus constituting what might be called the body of the abscess, and their appearance in the pus coming from the walls of the abscess a few ​days later, that the habitat of the parasite is not so much the pus occupying the general abscess cavity as that immediately in contact with the wall and the breaking-down tissues themselves. This is an inference entirely in harmony with Councilman and Lafleur's demonstration, confirmed by Marshall, of the parasite in the still living tissues around the abscess. In my experience the presence of the amœba does not affect prognosis unfavourably. Lafleur says it does: I cannot agree with him. In common with many other observers I have often seen amœbic liver abscess recover completely and rapidly after operation.
Other protozoa have been found in liver pus. Thus, both Grimm and Berndt have found numerous active flagella-like organisms therein. Some time ago, in the expectorated pus from a liver abscess discharging through the right lung, I found a ciliated infusorian resembling Balantidium coli.
In the pus of a large proportion of liver abscesses both microscopical examination and culture may fail to detect the usual pyogenic micro-organisms. To harmonize this well-established fact with modern views on the cause and nature of the suppurative process, it has been suggested that, though in these sterile abscesses micro-organisms had originally been present, they had subsequently died out. This view receives a measure of support from the fact that in a proportion of instances there is no difficulty in demonstrating in the pus the ordinary pyogenic bacteria and, sometimes, the Bacterium coli commune. It by no means follows from this circumstance, however, that bacteria are a necessary factor in the production of all liver abscesses.
Encystment.— In rare instances the pus of liver abscess, instead of possessing the chocolate colour and viscid consistency described above, is yellow and creamy. This is particularly the case when the abscess becomes encysted— an occasional event. The walls of these encysted abscesses are thick, smooth, resistant, and fibrous. In time their contents become cheesy, and ultimately cretified; in the latter event the cyst shrivels up and contracts to a small size. ​Pathology.— The pathology of liver abscess has been a fruitful source of speculation and controversy. Much confusion has crept into the question from attempts to separate, etiologically and pathologically, multiple from single liver abscess. The former is often called " pyæmic abscess" or "dysenteric abscess," and has been set down as being the peculiar sequel of dysentery; the latter has been called and considered the " tropical abscess " par excellence, and regarded as idiopathic and entirely unconnected with dysentery.
As already pointed out, a careful examination of cases and statistics shows that both forms of abscess, single and multiple alike, are, in the vast majority of instances, clearly associated with dysentery. In their respective clinical histories, in their symptoms, in the characters of their walls and contents, in the frequent presence of amoebae, single and multiple abscesses are practically identical. The only difference between them is a numerical one— a circumstance quite inadequate to base a doctrine of specific distinction upon.
The view which I incline to hold on this subject has already been partly given in the section on etiology. There are two factors which are principally concerned in the production of liver abscess: (1) the predisposing— weakening of the resistive faculty of the liver by chronic congestion or tissue degeneration, and, perhaps, other subtle changes brought about by a combination of climatic, dietetic, and other tropical conditions; (2) the exciting— some micro-organism, streptococcus, staphylococcus, Bacterium coli commune, or other parasite, but especially the amœba, which, coming from the ulcerated dysenteric colon, or by way of the portal circulation (Marshall has demonstrated amoebae in a thrombus in a branch of the portal vein), gains access to the liver and proliferates in the weakened tissues. In at least 90 per cent, of cases the micro-organism is associated with or derived from dysenteric processes in the colon. Whether the resulting abscess be single or multiple is more or less a matter of accident. ​If the weakened liver is efficiently inoculated at one point only, there is only one abscess ; if at many points, then there is multiple abscess. This is virtually, in a sense, Budd's theory expressed in modern terms.
An apparently weighty objection to this view is sometimes urged. Why, it is asked, if liver abscess be the result of septic absorption from a dysenteric ulcer, is it not a common sequel of typhoidal or of tuberculous ulceration in the tropics? McLeod has met this objection very ingeniously and, I believe, to a certain extent, correctly. He points to the fact that typhoidal and tuberculous ulcerations are surface lesions unattended with abscess formation in the wall of the bowel. In their case there is free escape of the products and germs of ulceration; whereas in dysenteric lesions, in addition to the superficial ulceration, there is often what is really abscess formation with burrowing and retention of pus below the mucous membrane, and therefore great liability to entrance of micro-organisms into the radicles of the portal vein. Liver abscess, therefore, according to this view, is a pyæmic process. Often, however, it must be confessed, the dysentery preceding liver abscess appears, judging from the symptoms, to be of the catarrhal rather than of a more severe type ; but even in this case it may be that the amœba penetrates the portal radicle without producing ulceration.
To what extent the amœba is concerned in the production of tropical liver abscess it is as yet impossible to state. If the frequency of its presence is any indication it must be the usual if not the only cause. If we watch the movements of this animal on the warm stage; and if we reflect that it lives and wanders about in the same very active way among the structures forming the walls of the liver abscess, and even in what are comparatively sound tissues, preceding, as it were, the suppuration, or rather, the necrotic process; and consider that it lives at the expense of these tissues, it is hard to resist the conclusion that the amœba must operate as a disintegrating and irritating agency. ​Kartulis suggests that it may act merely as a carrier of pus-forming bacteria. Others maintain that it is a harmless epiphenomenon, incapable in any way of inducing pus formation. As yet experimental pathology has not given a decisive answer to this, one of the most important questions in tropical pathology, though later experiments are very suggestive. Amœbic dysentery and liver abcesses have been produced in cats by numerous investigators by rectal injection both of amœbic dysenteric stools and sterile liver pus containing amœbæ; these organisms have been demonstrated in the liver pus and intestinal walls of these animals after death. Furthermore, Harris and Gauducheau have been able to produce dysentery and liver abscesses in dogs by similar injections of amœbic pus, the latter by the intravenous route.
Calmette, in view of the frequency with which he and others have found liver abscess to be sterile, suggests that the exciting agency is of a chemical nature, some irritating liquefying body derived from the decomposition processes going on upon the surface of the dysenteric ulcer.
Symptoms.— There is great variety in the grouping of symptoms in liver abscess. The following is a common history: The patient, after residing for some time in the tropics, enjoying good general health and living freely, was attacked by dysentery. In due course he appeared to recover, and resumed work, Several weeks or months elapsed when, after a wetting, or some such incident, he began to feel out of sorts, to suffer from headache, foul tongue, want of appetite, irregularity of the bowels, disturbed nights, excessive and unaccountable languor, irritability of temper, and depression of spirits. About the same time he began to be conscious of a sense of weight and fullness in the right hypochondrium. Later he became feverish, particularly towards evening, the oncoming of the febrile distress being sometimes preceded by a sense of chilliness. At times he had sharp stabbing pain in the right side in the region of the liver, perhaps a dry cough and, possibly, a gnawing, uncomfortable ​sensation or pain in the right shoulder. His friends observed that his face had become muddy and haggard. He was uneasy if he lay on his left side. The quotidian rise of temperature now became a regular feature, the thermometer every evening touching 102° F.— sometimes more, sometimes less and sinking to near normal by morning. He now began to perspire profusely at night, and even during the day when he chanced to fall asleep. He had to change his sleeping clothes once or even twice every night on account of the drenching sweats.
On examination it is found that the patient is somewhat emaciated; his complexion thick and muddy; his pulse 80 to 100; his tongue furred and yellowish; the palms of his hands and soles of his feet cold and clammy. As he lies on his back it is obvious, on inspection, that the epigastrium is too full for one so emaciated; and it is seen that the breathing is shallow and mainly thoracic. The right rectus muscle is rigid. Considerable discomfort, if not pain, is elicited by attempts at palpation and percussion over the right hypochondrium. The liver dullness extends an inch too high, and an inch or more beyond the costal border in the nipple line; posteriorly it rises to about the eighth rib in the line of the angle of the scapula. It is further observed that the line of dullness is arched along its upper border; and that it is altered by changes of position, the upper line descending when the patient lies on his left side or stands up; in the latter position the lower margin descends markedly in the epigastrium. On deep inspiration, percussion below the right costal border gives rise to much uneasiness or even to acute pain. Very likely one or two tender spots can be discovered on firm pressure being made with the finger-tips in some of the lower right intercostal spaces, or below the right costal margin. The spleen is not usually enlarged. Auscultation may detect pleuritic friction somewhere over the base of the right lung, or peritoneal friction over the liver itself. The urine, free from albumin, is scanty, high-coloured, and deposits urates. The blood shows well-marked polymorphonuclear leucocytosis. ​As the case progresses emaciation increases; hectic with drenching nocturnal sweats continues; the liver dullness and pain may further increase; or the general enlargement may somewhat subside, and percussion may reveal a pronounced local bulging, upwards or downwards. If the abscess which has now formed is not relieved by operation, after months of illness the patient may die worn out; or the abscess, which has attained enormous dimensions, may burst into the right lung or pleura, or elsewhere, and be discharged, and either recovery, or death from continued hectic and exhaustion or from some intercurrent complication, ensue.
Great variety in the urgency of symptoms.— Although the foregoing is a fairly common history in liver abscess, there are many instances in which the initial symptoms are much more urgent, and in which the disease progresses much more rapidly. In other instances subjective symptoms are almost entirely absent; or so subdued that the true nature of the case may be entirely misapprehended until the abscess bursts through the lung or bowel, or a fluctuating tumour appears in the neighbourhood of the liver; or, perhaps, not until after death, when the unsuspected abscess is discovered on the post-mortem table.
Fever.— In an acute sthenic case the initial inflammatory fever may run fairly high and persist for some time. Later, when it may be assumed that pus has formed, the fever becomes distinctly quotidian and intermittent in type, the morning temperatures being normal, or only slightly above normal, the evening rising to 101° or 102° F., or a little over or under this. Sometimes evening temperatures of 103°, rarely of 104°, are registered. In the asthenic and insidious type, at first there may be short flashes of feverishness at more considerable intervals, to be followed later by a steadier fever of a hectic type, as in the suppurative stage of the sthenic cases. In either type there may be afebrile intervals of several days' duration; and in either there may also occur, concurrently with aggravations of the local conditions, spells of continued high temperature. Occasionally, ​though rarely, liver abscess may be unattended by fever of any description whatever.
Rigors.— In the classical descriptions of liver abscess the occurrence of violent rigor is generally mentioned as a notable sign of the formation of pus. Undoubtedly such a rigor does at times signalize this event; but it is by no means constant, and its absence is no guarantee that abscess has not formed. Generally the evening rise of temperature is preceded by a sense of chilliness, sometimes by a more marked rigor simulating, in the regularity of its recurrences and in its severity, the rigor of a quotidian malarial fever.
Sweating, particularly nocturnal sweating of a very profuse character, is an almost invariable accompaniment of liver abscess. The patient's clothes may be literally drenched with perspiration. Even during the day— particularly, as already mentioned, if he chance to fall asleep— the sweat may stand in beads upon the forehead and around the neck. This, like most of the other symptoms, may be temporarily absent or, in a small proportion of cases, trifling.
The complexion is generally muddy, cachectic, and slightly icteric-looking; marked jaundice, however, is uncommon.
Wasting is generally decided and progressive.
Rheumatic-like pains and swelling of the hands and feet, such as occur in chronic septic affections, are sometimes to be noted. They usually disappear-rapidly when the abscess bursts or is opened and free drainage is established.
Pain of some description is rarely absent. In a few exceptional cases there is no pain; such a patient may declare that he does not know that he has a liver.
There are several types of pain— local and sympathetic— associated with liver abscess. Complaint is almost invariably made of a sense of fullness and of a sense of weight in the region of the liver, not infrequently referred to the infrascapular region. Stabbing, stitch-like pain, increased by pressure and ​especially by deep inspiration, by coughing and all sudden jarring movements, is very common, and probably indicates perihepatitis from proximity of the abscess to the surface of the organ. Percussion, or firm palpation, especially if practised during deep inspiration and below the ribs in front, generally causes smart pain and decided shrinking, the rectus muscle starting up as if to protect the subjacent inflamed parts. Pain on swallowing, at the moment the bolus of food traverses the lower end of the œsophagus, was mentioned to me by a medical man, himself the subject of hepatic abscess, as being a marked symptom in his own case. Pain on firm pressure with the finger-tips in an intercostal space, and over a limited area, is a common and valuable localizing sign. Among the sympathetic pains may be mentioned shooting pains radiating over the chest and down the right flank and hypochondrium.
Pain in the right shoulder.— This symptom is present in about one-sixth of the cases. It may be persistent, or it may intermit; it may radiate to the side of the neck, or to the region of the scapula, or down the arm; or it may be limited to the shoulder-tip and clavicular region. In some instances it is of a dull, gnawing, aching character; in others it is more acute; and in some it may be represented by a burning sensation, as if the surface of the skin had been flayed by a blister. This symptom is a reflex transmitted from the hepatic terminals of the phrenic through the fourth cervical to the branches of the cervical and brachial plexuses.
Cough of a dry, hacking character, doubtless also a reflex from irritation of the diaphragm, or from an inflamed condition of lung or pleura over the seat of abscess, is not uncommon. When the abscess discharges through the lung, cough is sometimes very severe and may cause vomiting.
Respiration is generally shallow and proportionately rapid. This is partly symptomatic of the attendant fever; oftener it is owing to the fact that fuller inspiration is attended with stitch. Sometimes the breathing is entirely thoracic, the lower part of ​the chest seeming to be fixed especially the right side— and the diaphragm almost motionless.
The decubitus is usually dorsal or right dorsal, the body being somewhat bent towards the right side and the right leg perhaps slightly drawn up. When the patient stands, a stoop to the right may be noticeable. Lying on the left side generally causes pain from dragging on adhesions, or discomfort from the pressure of the enlarged liver on the heart and stomach. Occasionally the decubitus is indifferent, or even on the left side.
The digestive organs are usually disturbed and the tongue is coated. Vomiting may occur from time to time, arising either from pressure on the stomach by the swollen liver or as an expression of gastric catarrh ; appetite, as a rule, is poor; flatulence may be troublesome; the bowels are confined or irregular, or there may be diarrhœa or dysentery. In the case of concurrent dysentery, it may be noted sometimes that the hepatic and dysenteric symptoms alternate in severity.
The area of hepatic percussion dullness is usually extended upwards and downwards, and sometimes horizontally. The extension may be general, especially in the earlier stages; later, careful outlining of the upper and lower boundaries may discover a limited and dome-like increase in one direction, most significant if upwards. The upper line of dullness is not, as a rule, horizontal, as in hydrothorax; almost invariably, on approaching the spine, it trends downwards more markedly than in hydrothorax or empyema. Variations in the extent of the dullness may take place from time to time, and sometimes very rapidly, depending not on fluctuations in the size of the liver abscess, but on the varying and relative amounts of local and general hepatic congestion. One sometimes finds even a narrow hepatic dullness in the nipple line, with a great increase in the axillary or scapular lines. In one case the lower border of the liver may be as low as the umbilicus; in another, especially in front, it may be well inside the costal margin. Diagnosis in the latter type of case is difficult, and depends ​rather on the nature of the fever and on the history and general condition than on local signs.
Splenic enlargement may be present even when there is no malarial complication. This is rare, however, and in uncomplicated cases is seldom great. I have seen splenic tumour closely simulated by abscess in the left lobe of the liver.
Varicosity of the epigastric and hœmorrhoidal veins— one or both— is sometimes discoverable.
Œdema of the feet and ascites are rare in the earlier stages; but the former is very usual towards the termination of long-standing cases.
Local œdema over one or more intercostal spaces, or more extensive and involving the whole or part of the hepatic area, is sometimes apparent. When limited it is a useful locating symptom.
Local bulging, if attended with fluctuation, indicates the presence of pus near the surface and the pointing of the abscess. Usually this, when it occurs, is in the epigastrium; but pus may burrow and find its way down the flank, or among the muscles of the abdominal wall, and open perhaps at a point remote from the abscess cavity in the liver.
Friction, both pleuritic and peritoneal, is sometimes to be made out, and is not without its value as a localizing symptom.
Pneumonia, generally limited to the base of the right lung, and of a subacute and persistent character, indicates contiguity of the abscess to the diaphragm. It is especially common in those cases in which the abscess subsequently ruptures through the lung. This form of chronic pneumonia is a fruitful source of error in diagnosis.
Chronological relation of the hepatitis to the dysenteric attack.— This is most irregular and uncertain. In many cases of dysentery a concurrent hepatitis is manifest almost from the commencement of the attack; this hepatitis may not subside, but pass directly to abscess formation. Or the initial hepatitis and dysentery may both subside apparently, but the former may recur weeks, months, or even years afterwards, when, perhaps, the attack of dysen​tery is almost forgotten. Or there may be no active hepatic symptoms with the dysentery, hepatitis supervening only when all bowel trouble has long passed away. In a few cases no dysenteric history can be elicited; it is seldom, however, as has already been insisted on, that careful inquiry fails to bring out some story of previous bowel disturbance more or less urgent. In a few instances liver abscess of tropical origin does not declare itself until the patient has been several years resident in a temperate climate and quite outside the endemic area.
The incidence of the symptoms is equally variable. Some cases commence with marked sthenic fever, much local pain, great tenderness and hepatic enlargement, the signs of suppuration, as rigor, hectic, and local bulging, rapidly supervening. Others, again, commence so insidiously that the patient can hardly say when he first began to feel ill; perhaps there may be a history of slow deterioration of the general health during a year or longer before definite hepatic symptoms show themselves. The former type seems to be the more common in the young and robust new-comer to the tropics; the latter, in the more or less cachectic and old resident. Between these extremes there is endless variety.
Duration of the disease.— Liver abscess may run its course in three weeks. Generally it is an affair of several months. Sometimes it may run on for a year or even longer; particularly so if it burst through the lung and drainage be imperfect, in which event the cavity may keep on bursting and refilling at intervals for almost an indefinite period. Occasionally a liver abscess becomes encysted and gives rise to no further symptoms, its existence being discovered only on the post-mortem table, the patient having died of quite another and independent disease.
Terminations.— Apart from operative inter- ference, liver abscess may terminate in various ways. It may end in spontaneous rupture leading to death or recovery. Death may also be brought about in other ways— by the severity of the local disease; by prolonged hectic and exhaustion; by concurrent ​dysentery; or by intercurrent disease, as pneumonia, pulmonary abscess, empyema, peritonitis. Recovery may also ensue 011 the abscess becoming encysted or, possibly, absorbed.
Rupture of the abscess.— Rendu, in a series of 563 instances of abscess of the liver, compiled from various sources, gives an interesting table showing the direction of rupture in 159 of the cases which opened spontaneously. This table may be summarized as follows:
| Rupture | occurred | into the | pericardium | in 1 | case | 0·13 | per cent. |
| Rupture„ | occurred„ | into the„ | pleura | 31 | cases | 5·5 | per cent„ |
| Rupture„ | occurred„ | into the„ | lung | 59 | cases„ | 10·5 | per cent„ |
| Rupture„ | occurred„ | into the„ | peritoneum | 39 | cases„ | 6·9 | per cent„ |
| Rupture„ | occurred„ | into the„ | colon | 6 | cases„ | 1 | per cent„ |
| Rupture„ | occurred„ | into the„ | stomach and duodenum | 8 | cases„ | 1·4 | per cent„ |
| Rupture„ | occurred„ | into the„ | bile-ducts | 8 | cases„ | 0·7 | per cent„ |
| Rupture„ | occurred„ | into the„ | vena cava | 3 | cases„ | 0·5 | per cent„ |
| Rupture„ | occurred„ | into the„ | kidney | 2 | cases„ | 0·3 | per cent„ |
| Rupture„ | occurred„ | into the„ | lumbo-iliac region | 6 | cases„ | 1 | per cent„ |
From this it will be seen that about 28 per cent, of liver abscesses rupture spontaneously, most generally into the lung or pleura.
Rupture into the lung.— If rupture takes place into the lung the abscess contents may be suddenly discharged, mouthful after mouthful of pus mixed with blood welling up or being coughed up. In a few instances, in such circumstances, death has occurred suddenly from the flooding of the lungs with pus. More commonly the discharge is effected gradually, a few drachms being brought up with each cough ; in the aggregate this discharge may amount perhaps to 5 or 10 oz. in the twenty-four hours. In favourable cases the daily amount expectorated gradually diminishes until all discharge ceases and the patient recovers. Frequently, however, a deceptive arrest of discharge and cessation of cough are followed by a rise of temperature, which had become normal on the occurrence of rupture. With this there may be a reappearance of the night sweats. In a few days cough and expectoration return as ​before and fever once more subsides. This process of alternate emptying and refilling of the abscess cavity may recur many times before recovery finally takes place. In some cases it continues for months, and may finally wear out the patient. Abscess may form in the lung ; or a sudden and fatal hæmoptysis may be brought about by ulceration opening some large pulmonary vessel. In some, expectoration never altogether ceases; if accompanied by fever this persistency indicates imperfect drainage, or, possibly, the presence of a second and unruptured abscess.
Characters of the expectorated liver pus.— The appearance of expectorated liver pus is almost pathognomonic. In colour it is chocolate brown; in consistence it is viscid and jelly-like. It may be streaked with blood; sometimes the expectoration may be almost entirely pure blood. Not infrequently these hæmorrhagic cases are regarded and treated as examples of ordinary hæmoptysis. Presumably, in the majority of instances, this blood comes from the wall of an abscess jarred and torn by the succussion of the harassing cough. Under the microscope expectorated liver pus exhibits the appearance already described (p. 582).
Rupture into the pleura leads to sudden development of evidences of pleural effusion which, unless relieved by drainage, may, in its turn, give rise to all the signs of empyema, and terminate in death, or in rupture through the lung or chest wall.
Rupture into the stomach is generally signalized by vomiting of the characteristic pus and, at all events temporarily, by cessation of local symptoms and fever.
Rupture into the bowel may cause diarrhœa, the pus, more or less altered, appearing in the stool. This is an occurrence that is frequently overlooked.
Rupture into the pericardium, or into a blood-vessel, is almost necessarily and rapidly fatal.
Rupture into the peritoneum is, of course, a serious occurrence, but, I believe, not necessarily fatal. The majority of liver abscesses, as will be presently described, do not contain the ordinary septic bacteria, ​and, therefore, may not give rise to septic peritonitis. I have seen recovery after this accident, the peritoneum having been well washed out and drained.
Rupture through the skin is said to be the most favourable, though a rare termination of liver abscess.
Mortality.— Rouis (203 cases), in Algiers, observed a mortality of 80 per cent.; Castro (125 cases), in Egypt, a mortality of 72.5 per cent., or, excluding cases operated on, of 76 per cent. In the Indian army, during the period 1891-4 (prior to which abscess of the liver, in the statistical returns, is not separated from hepatitis), and, presumably, including cases operated on, the mortality was 57.7 per cent.
Causes of death.— In Rouis's 162 fatal cases the causes of death are stated as follow: Severity of the local disease, or through the associated dysentery, 125; bursting of the abscess into the peritoneal cavity, 12; into the pleura, 11; gangrene of abscess wall, 3; peritonitis, 3; pneumonia from effusion of liver pus into the lung, 3; rupture of adhesions, 2; pneumonia, 2; rupture into the pericardium, 1. Abscess in the brain is a rare but occasional cause of death; in one recorded case amoebae were found in the pus.
Diagnosis.— Of all the grave tropical diseases none is so frequently overlooked as abscess of the liver. Acute sthenic cases are readily enough recognized; not so the insidious asthenic cases. The novice in tropical practice is some time in realizing that grave disease of so important an organ as the liver may, for a long time, be unattended with urgent symptoms, whether local, or constitutional, or both.
The most common mistakes in diagnosis are: (1) Failure to recognize the presence of disease of any description, even when an enormous abscess may occupy the liver. (2) Misinterpretation of the significance and nature of a basic pneumonia— a condition so often accompanying suppurative hepatitis. (3) Attributing the fever symptomatic of liver abscess to malaria. (4) Mistaking other diseases for abscess of the liver, and vice versa— for example, ​hepatitis of a non-suppurative nature, such as that attending malarial attacks; suppurative hepatitis before the formation of abscess; syphilitic disease of the liver— softening gummata which are often attended with fever of a hectic type; pylephlebitis; suppurating hydatid; gall-stone and inflammation of the gall-bladder; subphrenic abscess; abscess of the abdominal or thoracic wall; pleurisy; encysted empyema; pyelitis of the right kidney; pernicious anæmia; leucocythsernia; scurvy and similar blood diseases associated with hepatic enlargement; ulcerative endocarditis; kala-azar; undulant fever; trypanosomiasis. Any of these may be attended with fever of a hectic type, increased area of hepatic percussion dullness, and pain in or about the liver.
Many times a correct diagnosis can be arrived at only by repeated and careful study of the case in all its aspects. Golden rules in tropical practice are to think of hepatic abscess in all cases of progressive deterioration of health; and to suspect liver abscess in all obscure abdominal cases associated with evening rise of temperature, and this particularly if there be enlargement of or pain in the liver, leucocytosis, and a history of dysentery not necessarily recent dysentery. If doubt exist, there should be no hesitation in having early recourse to the aspirator to clear up diagnosis, after employing emetine or ipecacuanha as a therapeutic test.
As bearing on prognosis, apart from the risk from sudden rupture in some untoward direction, to overlook abscess of the liver is a much graver error than to mistake some other disease for liver abscess; for the chances of recovery from operation are proportionately prejudiced by every day's delay.
Low pneumonia of the right base in a tropical patient should always be regarded with suspicion; in most instances it means abscess of the subjacent liver.
Perhaps the most common error is to regard the hectic of liver abscess as attributable to malaria. The regularity with which the daily fever recurs, the daily chilliness or even rigor coming on about the same hour, the profuse sweating, and other circum​stances so compatible with a diagnosis of malaria, all contribute to this mistake. So common is the error that Osier says he hardly ever meets with a case of liver abscess which has not been drenched with quinine. My experience is the same. I have seen medical men make this mistake not only in their patients but in their own persons. If carefully considered, there are several circumstances which should obviate so serious an error. (1) No uncomplicated ague resists quinine in full doses. (2) In malaria, if the liver be enlarged the spleen is still more so; the reverse is the case in liver abscess. (3) The malaria parasite cannot be found in the blood in non-malarial hepatitis. (4) In liver abscess the fever is almost invariably an evening one; in malaria it most frequently comes on earlier in the day. (5) Quotidian periodicity, contrary to what is the case with tertian or quartan periodicity, is by no means pathognomonic of, or peculiar to, malaria. (6) The almost invariable history of antecedent dysentery, or, at least, of bowel complaint, in liver abscess. (7) Polymorphonuclear leucocytosis in liver abscess: relative mononuclear leucocytosis in malaria, kala- azar, and trypanosomiasis.
To mistake other forms of suppuration for liver abscess is of no great moment, because in many of the suppurative diseases just enumerated the treatment is the same as for liver abscess, and no bad result need be looked for if diagnosis is not quite accurate. A more serious error, however, is to overlook the presence of leucocythæmia, pernicious anæmia, or scurvy, and to proceed to aspirate an enlarged liver on the supposition that the symptoms arise from abscess. Fatal intraperitoneal hæmorrhage from the puncture has been known to ensue in such circumstances. If any doubt is possible on this point, a microscopical examination of the blood should be made before proceeding to explore.
A point to note in exploring is that, when the instrument enters the liver, an up-and-down pendulum-like movement will be communicated to the outer extremity of the needle, in harmony with the rising ​and falling of the organ in respiration. If the needle does not exhibit this movement, its point may be in an abscess cavity, but this abscess is not in the liver.
Treatment.— Hepatitis which has not proceeded to abscess formation should be treated, especially if dysentery be present or have been antecedent, with full doses of emetine or of ipecacuanha, repeated once or twice a day for two or three days or longer, by a cautious use of the purgative sulphates, and with poultices, rest, and low diet. Rogers has recently reiterated the value of emetine and ipecacuanha in such circumstances. If there be much pain, relief may be afforded by either wet or dry cupping over the liver, or by leeches around the anus. Ammonium chloride, in 20-gr. doses three times a day, is usually prescribed.
When the occurrence of rigor, or the development of hectic, or the appearance of local bulging, or the persistency of the fever and of the local symptoms, gives ground for suspecting that abscess has formed, active medication must be suspended, a somewhat improved dietary prescribed, and measures taken without unnecessary delay to locate by means of the aspirator the position of the pus.
When he proceeds to use the aspirator, the surgeon must be prepared to open and drain the abscess if pus be discovered once diagnosis is established, nothing is gained by delay. By proceeding to open the abscess at once, the shock of a double operation is avoided, and only one administration of the anæsthetic is required.
To facilitate aspiration, as well as the subsequent operation if such should be found to be necessary, the patient ought invariably to be placed under an anæsthetic. Unless in very special and exceptional circumstances, it is a mistake to attempt exploration without this, for the surgeon ought to proceed with deliberation and to feel himself at liberty to make as many punctures as he may think necessary. A medium- or full-sized aspirator needle should be used, as owing to the nature of the pus it may not flow through a cannula of small bore. ​If there are localizing signs, such as a tender spot, a fixed pain, a localized œdema, localized pneumonic crepitus, pleuritic or peritoneal friction, these should be taken as indicating, with some probability, the seat of the abscess and the most promising spot for exploratory puncture. If none of these localizing signs is present, then, considering the fact that the majority of liver abscesses are situated in the upper and back part of the right lobe, the needle should, in the first instance, be inserted in the anterior axillary line in the 8th or 9th interspace, about 1 in. or 1½ in. from the costal margin and well below the limit of the pleura. The instrument should be carried in a direction inwards and slightly upwards and backwards and, if found necessary, to 3 to 3⅓ in. If pus be not struck the needle must be slowly withdrawn, a good vacuum being maintained the while in case the abscess has been transfixed and the point of the needle lodged in the sound tissue beyond. No pus appearing in the aspirator, the remainder of the dull hepatic area must be systematically explored, both in front and behind, regard being had to the lung and pleura on the one hand, and to the gall-bladder, large vessels, and intestine on the other. The peculiar colour— often like dirty-brown thick blood— of liver pus must not be allowed to deceive the operator into thinking that he has failed to strike the abscess.*
At least six punctures should be made before the attempt to find pus is abandoned. Provided there is complete absence of breath sounds, of vocal fremitus and resonance over the lower part of the right lung, and pus has not been reached from lower down, then the pleura or lung may be disregarded and puncture made anywhere below the line of the nipple and angle of the scapula, or wherever the physical signs suggest.
The surgeon should be encouraged to make early use of the aspirator by the fact that its employment, ​even where no pus is discovered, is not infrequently followed by rapid improvement in all the symptoms. Many such cases are on record. Hepatic phlebotomy, as Harley designated the removal from the liver of a few ounces of blood by the aspirator needle, is a measure of proved value in hepatitis. With due care, risk from hæmorrhage is small; it is very small indeed in comparison with the risk of allowing an hepatic abscess to remain undiscovered and unopened.
Some surgeons, in order to obviate the small risk from hæmorrhage attending aspiration through the abdominal or chest wall, prefer to expose the surface of the liver by a short incision and then explore. It is hardly necessary to add that strict aseptic precautions, in the way of purifying the patient's skin, the surgeon's hands, and all instruments, must be carefully observed.
Operation for abscess of the liver.— The following is the operation usually practised by English surgeons. It is substantially that described by Godlee in the British Medical Journal of January 11, 1890, to which the reader is referred for many valuable details and practical hints.
If pus is struck below the costal border, the aspirator needle being left in situ as a guide, the abdominal wall is incised down to the peritoneum. A 3-in. incision will give plenty of room. If firm adhesions be discovered, a sinus forceps is at once run along the needle, and pushed through the intervening liver tissue and into the abscess. The aspirator cannula is now removed, and the blades of the forceps are opened sufficiently, as it is being withdrawn, to make a wound in the liver big enough to admit the forefinger, which must now be inserted and moved about so as to enlarge the wound and to gain some idea as to the size and direction of the cavity of the abscess. A rubber drainage-tube, about as large as the finger, and provided with a flange, is cut to a suitable length, and carried by means of the forceps to the back of the abscess. The abscess is then allowed to empty itself. When pus no longer flows freely, a ​massive antiseptic dressing is applied and firmly secured by a broad binder or many-tailed bandage.
If, after division of the abdominal wall, no reliable adhesions be discovered between this and the liver, the capsule of the latter must be securely attached to the former by a double circle of stitches. The abscess is then to be opened, as above described, with sinus forceps. After stitching, some surgeons prefer, before opening the abscess, first to stuff the wound in the abdominal wall with iodoform gauze, and to wait for a day or two for adhesions to form. Others stuff the wound with gauze without previous stitching.
Should the abscess be struck through an inter-costal space, and if the latter be not deemed sufficiently wide to admit of manipulation and free drainage, a couple of inches of rib had better be excised. The diaphragm may then be stitched to the thoracic wall or, better, to the skin as well, when the abscess may be opened with forceps. To stitch the capsule of the liver to the diaphragm is a somewhat difficult proceeding; but if there are no reliable adhesions it had better be attempted, especially if the opening is to be made through a part of the liver covered by the peritoneum. If by any chance the pleura is opened during the operation, pneumothorax will result— an unfortunate but not necessarily a serious contingency. In this case the hole in the pleura must be carefully stitched in such a way that the pleural cavity is completely cut off before the diaphragm is divided and the abscess opened. Pus must not on any account be allowed to enter the pleural cavity; this, owing to the aspirating influence of inspiration, it would readily do if the smallest hole should remain patent. The young surgeon would do well to practise these operations on the dead body, and familiarize himself with the relations of the various structures involved.
Some operators of experience completely ignore the absence of peritoneal adhesions, and, even in these circumstances, open the abscess without previous stitching of peritoneal surfaces. The risk and danger of escape of pus into the peritoneal cavity, ​they hold, is very small if free drainage to the outside is secured. McLeod considers that, in the circumstances, stitches will not hold in the soft and inflamed liver tissue; he also considers that, in the event of the incision having to be made in the thoracic wall, removal of part of a rib is unnecessary. On account of the liability of a rubber drainage-tube to become nipped when the emptying sac causes a want of correspondence between the wound in the abdominal or thoracic wall and that in the liver, and, also, on account of facility of introduction during the subsequent dressings, this operator uses metal drainage-tubes of suitable lengths— 4 in., 3¼ in., 2½ in., and 1¾ in.— with an oval lumen of 4/10 in. by 3/10 in. These tubes he introduces by means of a special guide.
The author's method.— The following easy, rapid, and efficient method of operating on abscess of the liver I have frequently practised, and can recommend. The necessary apparatus (Fig. 84), which can be made by native workmen, consists of a large trocar and cannula (a), 4 to 5 in. long, by ⅜ in. in diameter; a steel stilette (b) at least 14 in. in length; two metal buttons (c, d), ¼ in. at their greatest diameter, with long (½ in.), hollow, roughened necks into which the ends of the stilette fit loosely; 6 in. of ½-in. stout drainage tubing (c). While the ends of the drainage tubing are held and well stretched by an assistant, they are firmly lashed to the stem of the buttons, over the ends of the shorter (d) of which, for additional security, the tubing is also tied (c). Two large holes, to provide for free drainage, are now cut close to one end of the drainage-tube. The tube is then mounted on the stilette by inserting one end of the latter through one of the drainage holes and lodging it in the hollow neck of the distal button (e),and thereafter so stretching the rubber that the other end of the stilette can be inserted into the neck of the other button (d). When thus stretched the drainage-tube should be capable of passing easily through the cannula. The apparatus being so prepared and rendered thoroughly aseptic by soaking in carbolic lotion, and the direction of the abscess and its depth ​from the surface having been carefully ascertained by means of the aspirator and noted, the aspirator is withdrawn and an incision, about 1 in. in length, made through the skin at the site of the puncture. The trocar and cannula are then thrust into the abscess and the trocar withdrawn. After allowing a small quantity of pus to escape, so as to relieve any tension that may be present in the abscess sac,
Fig. 84.—Apparatus for operation for abscess of the liver ($a$ and $b$ reduced).
the stretched drainage-tube, perforated end first, is slipped into the cannula and carried to the back of the abscess. Holding the stretched drainage-tube firmly, and maintaining it carefully in contact with the back of the abscess with one hand, withdraw the cannula with the other. The drainage-tube still firmly grasped, the button on the free end of the apparatus is slipped off the stilette, the end of which is made to perforate the drainage-tube close to the button. This it readily does, and the drainage​tube is allowed slowly to resile towards the fixed end still held in contact with the back of the abscess. When the drainage-tube has completely contracted, the stilette is withdrawn. The drainage-tube is then transfixed with a safety-pin inserted close to the skin, and the superfluous tubing cut off. Pus flows freely from the tube, which now firmly plugs the wound in the abdominal wall and liver, and bridges the peritoneal cavity. When the abscess has nearly emptied itself the usual antiseptic dressing is applied. In operating through the thoracic wall, if deemed desirable, part of a rib may be excised before the trocar is introduced.
I claim for this operation that it is easily done, and that it may be undertaken by the merest tyro in surgery and in the absence of skilled assistance; that there is no risk from bleeding; that, the peritoneum being bridged across by the drainage-tube which is securely grasped by the liver tissue, there is no risk of escape of pus into the peritoneal cavity; that in a very short time lymph is effused around the tube, giving additional security when, after a time, the tube has become loose; that, if deemed necessary, a larger drainage-tube, by stretching it on the stilette in the same way as described, can be substituted for the ½-in. tube; that an abscess deep in the liver can be as readily opened, and with as little risk, as one lying near the surface; that the shock is much less than in the cutting and tearing operation; that there is no risk of pneumothorax should the pleural cavity be traversed ; and that the drainage obtained is equal to that secured by any other method of operating. Several of my surgical friends have adopted this method of operating, and have expressed great satisfaction with the ease with which it is performed, and with the results.
Other operations.— Some Continental surgeons recommend extensive incision of the liver, using a Paquelin's knife with the view of minimizing bleeding. Zancarol, for example, advises that the hepatic and integumental incisions should extend the whole breadth of the abscess cavity, which he mops out and ​stuffs with iodoform gauze. Certain French surgeons recommend scraping the abscess cavity; most practise irrigation with some antiseptic fluid. These methods do not find favour with English or Indian surgeons.
The method of opening the abscess by caustics, formerly much in vogue, is now abandoned; equally so another method, also formerly employed namely, that of leaving a rigid trocar in the wound.
Treatment after operation.— For the first few days after a liver abscess has been opened the discharge is considerable, and the dressing may have to be changed frequently. Very soon, however, should the case do well, the discharge rapidly diminishes, and the dressing requires renewal only every other day or every three or four days. During the first week the drainage-tube, provided it be acting efficiently, should not be disturbed, more particularly as it may be difficult to replace. Later, it may be removed and cleaned, and, when discharge has practically ceased, cautiously shortened. It is a great mistake to begin shortening the tube before it is being pushed out, or so long as there is any appreciable discharge. If there is the slightest indication, such as rise of temperature, that pus is being retained, the drainage must be rectified and the sinus, if necessary, dilated with forceps and finger, and a full-sized drainage-tube introduced as far as it will go. If this does not suffice, a counter-opening may have to be made. Delay in remedying imperfect drainage is a serious, it may be fatal, error.
Should an abscess on being opened be found to be septic, or should it become so, it must be flushed out daily, or twice a day, with a weak non-mercurial antiseptic, and a counter-opening made if necessary. Quinine solution— 1 in 1,000 normal saline— is useful if much amoeba-laden discharge persists for a length of time.
After liver abscess has been opened and is draining well, temperature rapidly falls, and in a few days, or almost at once, becomes normal. Should fever persist, it is to be inferred either that the drainage is inefficient, or that there are more abscesses in the liver, or that there is some complica​tion. If it be deemed that there is another abscess, this should be sought for with the aspirator, and, if found, opened and drained. I have seen a patient recover after three abscesses had been so treated.
It is advisable to give emetine* hypodermically, both before and after operation. Lately cases of liver abscess have been successfully treated by emptying the abscess by aspiration and injecting the cavity with emetine solution.
Treatment of abscess discharging through the lung.— In the case of abscess discharging through the lung, and, although emetine has been freely administered, not progressing favourably, the question of obtaining by surgical means more efficient drainage must be considered. There are two possibilities which render interference desirable: (a) Continued discharge of pus and blood, with or without attendant hectic; a condition which, if it persist, will, in all probability, in the end kill the patient. (b) Not infrequently prolonged discharge through the lung may induce fibrotic changes in that organ, or may give rise to pneumonia, or to abscess of the lung with all its attendant dangers, such as thrombosis or abscess of the brain. In these circumstances it is sometimes difficult to arrive at a decision as to whether an attempt should be made to open and drain the abscess, or to leave it alone. A large proportion of the cases recover, but at least an equally large number die. Of the latter, a proportion may certainly be saved by timely surgical interference.
In all cases of abscess discharging through the lung a careful register should be kept of three things —body temperature, daily amount and character of expectoration, and, once a week, the weight of the patient. If temperature keeps up, if the amount of pus continues the same or increases, or if the patient continues to lose weight, an attempt should be made at all risks to reach and drain the abscess from the ​outside. If temperature keeps normal, if pus gradually or intermittently decreases, and if the body-weight is maintained or increases, operation is unnecessary, or, at all events, should be deferred.
In exploring the liver in such cases it must be borne in mind that most likely the abscess cavity is collapsed, and that the sides of the abscess may be in contact. Such an abscess is not likely to be discovered unless the needle be thrust in to its full extent, and, whilst a good vacuum is being maintained in the aspirator, slowly withdrawn. If by good fortune the abscess has been traversed, then, when the end of the needle is crossing the cavity, a small amount of pus will be seen to flow. Great care must now be exercised to keep the needle in position so as to serve as a guide in opening the abscess. Recovery has been known to follow the introduction of a drainage-tube in the presumed direction of such an abscess, even although the abscess cavity was not entered, much less drained, by the tube.
Treatment of abscess rupturing into a serous cavity.—When there is evidence that an abscess of the liver has ruptured into the peritoneum, into the pleura, or into the pericardium, the particular serous cavity involved must be opened at once and treated on general surgical principles ; otherwise the patient will almost surely die. In the circumstances the surgeon will be justified in assuming great risks.
The prognosis in early operations on single abscess of the liver, provided there is no dysentery or other complication, is good. In multiple abscess, or in single abscess if there is active dysentery or other serious complication, prognosis is bad. In multiple abscess, if there are more than two or three abscesses, it is necessarily hopeless.
The question of return to the tropics after recovery from liver abscess frequently crops up. If feasible, and if the patient has not to make too great a sacrifice, he ought to remain in a temperate and healthy climate. There are many instances, however, of individuals who have enjoyed permanent good health in the tropics after recovery from liver abscess.
* ↑ * Dr. Rees informs me that liver abscess is more common among the natives of Nigeria than these figures seem to show it to be among the natives of India. Among the negroes, he says, the mortality in dysentery is much higher than among Europeans resident in Nigeria. Of those negroes attacked with dysentery who lived long enough, many subsequently developed liver abscess. Liver abscess is common in Indian immigrants in Fiji, in whom also amœbic dysentery is common, whereas in the native Fijian both amœbic dysentery and liver abscoss are rare (Bahr).
* ↑ * I have seen the peculiar brownish fluid resulting from the action on blood of the carbolic lotion that had been used to sterilize the exploring syringe, mistaken for pus. To obviate so grave a mistake the exploring syringe should be washed out with boiled water before use.
* ↑ * A case has been recorded of a patient who, refusing operation, was completely cured by emetine injections— 21 gr. being administered altogether; of another in whom the abscess burst into the lung and all discharge ceased on the administration of emetine.