Chapter IV: Front Matter (4)

The distinction between carcinoma and sarcoma cannot always be made during life, nor indeed, without a microscopical examination, after death. It is of importance chiefly with reference to prognosis after operation for removal of the organ. A more rapid growth, a greater tendency to invade other organs, and a more marked cachexia would speak in favor of carcinoma, while a tumor gradually attaining a very large size, and not spreading beyond the kidney and its immediate envelopes, is more likely to be a sarcoma.

There is no TREATMENT known to be of value in cancer or sarcoma of the kidney, except so far as it may diminish pain or regulate the secretions. Surgically, removal of the diseased organ is the only expedient to be thought of. Although nephrectomy has been shown to be a perfectly practicable operation, and one that is usually well borne when the other kidney is sound, it has not proved very successful with malignant growths, even as a temporary expedient. This is partly at least to be accounted for by the difficulties lying in the way of diagnosis in the earlier stages, and the reluctance with which so serious an operation would naturally be resorted to until hopes based either on the uncertainties of diagnosis or mistaken reliance on medical treatment have been given up. Cases, however, have been reported where patients have recovered from the operation, and the disease has not returned for some months. When an operation has been resorted to, the tumor has usually become too large to be extracted through the loin, and laparotomy has been the course {63} pursued. According to Billroth,[22] out of 33 operations for tumors of the kidney, 13 have been cured.

[Footnote 22: _Mittheil. der Aerzte in Nieder Oesterreich_, Bd. x. p. 161 _et seq._]

Cysts.

Three kinds of cysts are met with in the kidney besides those connected with the growth of parasites.

Kidneys congenitally affected with cystic degeneration contain a large number of sacs lined with a vascular membrane, among the partitions of which are found the remains of secreting structure. Both kidneys are equally affected, and are enlarged and more or less lobulated. They are occasionally so large as to constitute an obstacle to labor, and various operative procedures, even evisceration, have been required to accomplish the delivery of the foetus affected. The cysts are filled with fluid of various degrees of darkness of color from almost perfect limpidity to almost black. The fluid in the smaller cysts, at least, contains some of the urinary solids. The slighter degrees of this affection do not render a child necessarily non-viable, but with the larger some accident is likely to happen.

The formation of these cysts has been referred to an intra-uterine chronic nephritis, but another theory accounts for them by a vice of development. The fact that when the lesion is unilateral, as sometimes happens, there is apt to be a deficiency of some other part of the genito-urinary apparatus on the same side, and that several infants with cystic degeneration have been born of the same mother, speaks strongly in favor of the latter theory.

Serous cysts of later origin do not usually attain so large a size, or rather the kidney does not, on account of their smaller number. They are lined with a thinner membrane, and their contents are nearly clear, but coagulable, comprising uric acid, carbonate of lime, and cholesterin. Occasionally a single cyst attains considerable dimensions and produces by its pressure atrophy of part of the kidney. These cysts are supposed to arise in consequence of the blocking of a tube.

The third class of cysts closely resemble the first in appearance and in form, and contain more or less serous or gelatinous fluid, with albumen, blood-corpuscles, and pus, as well as the peculiar colloid bodies previously mentioned. They undoubtedly arise from the distension of tubes and of Malpighian bodies. These cysts are usually associated with chronic interstitial nephritis, and in fact they are rarely absent in cases of this kind, although the extreme degree--that is, where the cysts assume the most prominent position while the contracting nephritis falls into the background--are less common. In these latter cases the organ may be almost transformed into a mass of rounded bodies somewhat resembling a bunch of grapes.

The SYMPTOMS of the first two of these conditions--that is, of the cysts which are not connected with an active nephritis and attract attention simply as tumors--depend on the pressure they exert; and a diagnosis is to be made by a knowledge of their history and by the rules already given. The symptoms and diagnosis of the third variety are involved in those of chronic interstitial nephritis.

{64} There is no reason to suppose that any drug has any therapeutic action on such kidneys, so far as the cysts are concerned. It should always be remembered that a kidney may contain a large number of cysts, and yet scattered portions of secreting substance enough be left to carry on the function indefinitely.

It might under some circumstances be justifiable to remove a cystic kidney on account of the pressure exercised on other organs, but as the cysts do not increase rapidly in size, punctures several times repeated, so as to empty a number of them, would in most cases prove as effectual an operation, and, what is of greater importance, would not involve the loss of any portion, even if small, of secreting structure which may be left.

Tuberculosis.

The tubercles which are found in the kidney in cases of general miliary tuberculosis have usually no clinical interest, since the kidney is not, even in children, one of the points where tubercular localization is most intense, and renal tubercles are consequently but little advanced when death takes place from the extension of the disease in other organs. They present no symptoms which are perceptible among the much graver ones attending the progress of the disease elsewhere.

In the disease known as tubercle of the kidney, caseous nephritis, or nephro-phthisis, masses of caseous material are deposited in the renal parenchyma which may soften, break down, and communicate with each other and with the calices and pelvis. In some cases it is probable that the disease originates in or immediately underneath the mucous membrane of the urinary passages. This process of breaking down continues much in the same way as that of a phthisical lung, until the kidney becomes little more than a hardened, irregular, knobby shell enclosing a ragged, ulcerated cavity with thickened, pus-secreting walls and filled with pus, more or less blood, and débris of kidney-structure and tubercle. In such portions of renal substance as may remain it is not unusual to find miliary tubercle. If obstruction of the ureter exists, a pyo-nephrosis may exist in addition. Rupture into the peritoneal cavity or into the intestine has occurred.

It is probable that in this affection are included two processes, differing in pathology and etiology and to some extent in clinical history. It is probable that true tubercle may originate in the kidney as a result of either tubercle or cheesy inflammation elsewhere, as in the lungs, bodies of the vertebræ, or scrofulous glands. In this case there are no marked symptoms until the process of softening and breaking down has reached the mucous membrane of the pelvis. Besides this, renal phthisis sometimes succeeds, as a more local invasion, to tubercle or cheesy inflammation of the urinary passages, and in this case the symptoms appear simply as aggravations of those already present and depending upon ureteritis and pyelitis. Renal phthisis is seldom if ever an independent disease. It is often associated, besides the affections already named as standing in etiological relationship with it, with cheesy inflammation of the testicle, vesiculæ seminales, and much less frequently of the ovaries and Fallopian tubes.

{65} The DIAGNOSIS of tubercle in the kidney before it has reached the pelvis is probably impossible. Pain in the back or slight albuminuria, as has been already stated, is of no diagnostic value except as pointing to some renal irritation, as to the cause of which it tells nothing. In the presence of tubercle elsewhere it might be regarded as suspicious.

After cavities have become connected with the pelvis or have extended from it, the symptoms become more marked. In the urine are to be found pus, some blood, epithelium of the urinary passages and often of the kidneys, in many cases in the form of casts; and it is claimed that masses of caseous matter as large perhaps as the head of a pin may be found, which will of course make the diagnosis almost a matter of certainty. If the urine containing such a deposit is acid, it is almost certain that the lesion is mainly in the kidney and that the bladder is but slightly if at all affected. It is also stated that the bacillus of tubercle has been found. The presence of this parasite will not only testify as to the presence of the clinical condition known as phthisis of the kidney, but will also make it sure that the affection depends upon tubercle in the strictest pathological sense, and will influence the prognosis accordingly. Inoculation of purulent sediment from the urine of a patient suffering from tuberculosis of the urinary passages has produced tubercle in the iris of the rabbit. This procedure has been suggested as a means of diagnosis as to the character of a chronic catarrh of these passages before the appearance of tubercle elsewhere.[23]

[Footnote 23: Ebstein, _Centralblatt für die Med. Wiss._, 1882, p. 918, from _Deutsch. Arch. f. klin. Med._, xxxi. S. 63.]

If pyelitis have already been present, the change in the appearance of the urine will be less characteristic, but there may be a marked aggravation of symptoms when the contents of softened masses are added to the secretions of the mucous surface. There is likely to be much fluctuation in the quantity of débris present from day to day. Urinary fever of the hectic or subcontinued type, with anorexia, nausea, dry tongue, and diarrhoea, is present. In some cases the enlarged and irregular kidney may be felt.

The PROGNOSIS of this condition is in the highest degree unfavorable, although the finding of cicatrices in kidneys where symptoms of renal phthisis have been present suggests that it is possible for caseous masses in these organs, as well as in the lungs, to undergo absorption and healing.

The TREATMENT must be, in the first place, constitutional by tonics and reconstituents, and local by the use of such antiseptics as are eliminated through the kidney, as boric or benzoic acid or the benzoates. But little, however, is to be expected from it.

Parasites.

The most important parasite which is known to inhabit the kidney is the immature tapeworm of the dog, or Tænia echinococcus. It is decidedly rare in this country to meet with this affection in any part of the body, and as the kidney is not one of the organs most likely to be chosen as its habitat, the condition is not one which comes often under the observation of physicians.

{66} It is hardly necessary to describe here the structure or contents of the hydatid cyst which forms the home of the parasite, nor its etiology, since these topics belong to general pathology, and the cyst is the same in whatever organ it may be seated. When it affects the kidney, it is usually the left--more frequently that of a man between thirty and forty years of age.

A hydatid cyst may be situated upon any part of the kidney. If small, it may never make its presence known. A larger one may give rise to those vague pains in the back found with so many diseases of the kidney and characteristic of none of them. A cyst may open in any direction, but is more likely to empty into the pelvis of the kidney. When this happens, the smaller cysts or pieces of the larger ones often enter the ureter and give rise to renal colic, and possibly, later, to a pyelitis. Other points of discharge are the intestines, the lungs, or the abdominal walls.

After a hydatid cyst has reached a certain size its presence may be recognized by palpation, but the diagnosis between it and other tumors of the kidney must be very difficult unless characteristic fragments make their appearance in the urine at the same time that the tumor diminishes in size, or unless they can be obtained by puncture. The hydatid thrill, if it can be obtained, will be an important factor in diagnosis.

The TREATMENT of this affection in the kidney presents no special points of difference from that of similar cysts in the liver; with this important exception, that besides punctures with large and small trocars, incisions, electrolysis, etc., the resource of complete extirpation still remains. Cures have been obtained by repeated punctures and subsequent suppuration, and by partial removal through the abdominal walls and subsequent drainage.

Among the parasites of the kidney it is customary to mention the Strongylus gigas, which is a worm somewhat resembling the ascaris and inhabiting the pelvis. It is not very infrequent among the Carnivora, but since only seven cases have been described in the human subject since the seventeenth century, and only a part of these are admitted as genuine by certain authors, its diagnosis, prognosis, and treatment must depend more upon theory than upon experience. The diagnosis is to be made, if at all, on the basis of a pyelitis and the discovery of the eggs of the parasite in the urine.

The Distoma hæmatobium is a parasite found chiefly in the blood-vessels, and especially those of the portal system. It is occasionally, however, met with in the veins of the kidney and also in the urinary passages. Its eggs pass into the pelvis and ureters, and there begin their development, which, however, is soon arrested, as they rapidly perish in the urine.

These parasites appear to produce either by a direct action or by the occlusion of vessels, ulceration, and hemorrhages from the urinary mucous membrane, including that of the bladder. These effects are supposed to be due to the blocking of the smaller vessels by the worms themselves. An adherent deposit consisting of masses of distoma eggs and grains of uric acid sometimes forms in grayish-yellow patches within the ureter, and gives rise to stricture, with dilatation and hydro-nephrosis above. This parasite has been considered the cause of the endemic hæmaturia of hot countries, but as cases of this affection have been carefully examined {67} for the distoma with negative results, it must be considered as only one among several causes. Strongyli are said to have been found in some of the cases.

Nothing is known of an appropriate TREATMENT for the distoma. An abundant flow of urine might perhaps carry off more rapidly such individuals as have found their way into the urinary passages, and, considering the character of the deposit described above as causing stoppage of the ureter, treatment directed against the uric-acid diathesis might diminish the risk of this particular form of trouble.

Diseases of the Ureters.

Absence of the ureter may take place when one kidney is congenitally absent, though this is not an absolute rule, since the ureter may terminate above in a rounded sac. When a single kidney exists, consisting of the fusion of two, there are usually two ureters opening in the usual position. In one instance, in which only one kidney and one ureter were present, the ureter opened into the bladder on the side opposite to that upon which the kidney was situated.

Not very infrequently two ureters exist in connection with a normal kidney, remaining separate for the whole or a part of their course to the bladder. This condition is merely a sort of exaggeration of the separation between the two branches of the renal pelvis.

A few instances have been noted where a ureter or a fistula connected therewith has opened outside of the bladder at a point near the urethra. This malformation gave rise to symptoms of incontinence of urine, and in one case was remedied by operation.

Abnormal openings of the ureter into the uterus and vagina as the results of pelvic inflammations, and upon the external surface as the result of wounds, have occurred. They are more or less amenable to surgical treatment, and belong to the domain of surgery and gynecology rather than to medicine.

Occlusion of the ureter has already been spoken of in connection with the hydro-nephrosis and pyelitis to which it gives rise. This occlusion results from pressure exerted either at the vesical orifice from cystitis; a little higher up from malignant disease connected with the uterus or a fibroma surrounding the ureter; from contracting adhesions resulting from pelvic inflammation; or from sharp flexions of the tube itself, perhaps also from valvular folds of the mucous membrane. Sometimes its obliteration seems to be the result of old inflammation of the mucous membrane of the ureter itself in connection with that of the renal pelvis. In the latter case the occlusion may be complete at several points, while at others a collection of dry, cheesy, or putty-like material occupies the cavity of the ureter as well as the pelvis of the atrophied kidney.

Cancer is not known primarily to invade the ureter.

Tubercle is not infrequently found in the form of small granulations in cases of general tuberculosis, and it is possible that this deposit may be among the earlier ones; hence a chronic catarrh of the urinary passages without some known cause should be looked upon with suspicion, {68} and the development of phthisis as far as possible guarded against. The presence of these small tubercles in the ureter, if none are present or no ulceration exists in the kidney, are of little or no local importance.

Inflammation of the ureter often exists in connection with cystitis and pyelitis, and in fact constitutes the means by which the higher urinary passages become gradually involved in the diseases below.

The DIAGNOSIS of this condition as a distinct disease is hardly possible, and is besides unnecessary, as the treatment to be directed thereto would be included in that called for by the more extensive and obvious inflammation of the kidney and bladder.

{69}

DISEASES OF THE PARENCHYMA OF THE KIDNEYS, AND PERINEPHRITIS.

BY FRANCIS DELAFIELD, M.D.

CHRONIC CONGESTION OF THE KIDNEY.

SYNONYMS.--Passive congestion; Cyanotic induration.

It is now generally recognized that we must separate from the other forms of kidney disease the condition of chronic congestion. Since Traube first called attention to the causation and characters of this lesion, all authors have recognized its special character, although there are still minor differences of opinion concerning it.

ETIOLOGY.--Chronic congestion of the kidney may be produced by any mechanical cause which interferes with the escape of the blood from the renal veins. Thrombi of the veins, tumors pressing on the veins, emphysema of the lungs, hydro-pneumothorax, pericarditis,--all may produce this lesion. As to how often it is produced by the pregnant uterus is still a question. But the most common cause of all is organic disease of the heart. Practically, the lesion comes under consideration as a complication of heart disease, of aneurism of the arch of the aorta, and of emphysema of the lungs.

LESIONS.--If the congestion has not existed for a long time, we find the kidneys increased in size and their weight great in proportion to their size. They are of an unnatural hardness--a hardness which can be imitated by injecting the blood-vessels of a normal kidney with water. The capsules are not adherent, the surfaces of the kidneys are smooth. Both the cortical and pyramidal portions are congested, and this congestion gives the entire organs a peculiar reddish, livid color. No lesions are found in the Malpighian bodies, tubes, stroma, or blood-vessels, except that the epithelium of the convoluted tubes may be a little swollen.

If the congestion has lasted for a longer time, the kidneys may continue to be large or they may be somewhat reduced in size; the weight remains out of proportion to the size. There are the same unnatural color and consistence. The capsules are now often slightly adherent and the surfaces of the kidneys finely nodular. In the cortex there may be patches of new connective tissue enclosing atrophied tubules, or there may be a more diffuse growth of connective tissue separating the tubes from each other. In the convoluted tubules the epithelial cells may be swollen and finely granular, or very much swollen and coarsely granular, so as to nearly fill the tubes, or flattened so that the cavities of the tubes are {70} unnaturally large. The tubes may also contain cast-matter and detached and broken epithelial cells. The capsules of the Malpighian bodies may be a little thickened and the capsular endothelium swollen. In the pyramids the epithelium of the straight tubes may be granular and detached, and there is often cast-matter in the looped tubes. It is difficult to tell whether there is any real change in the veins of the kidney.

As a result of the same interference with the venous circulation, similar changes are found in other parts of the body--in the lungs, liver, spleen, stomach, small intestine, and pia mater. In all these organs there is, first, simply a venous congestion, then after a time structural changes are added. Formation of new connective tissue and of new functional cells of the particular organ, degeneration of these cells, dilatation and tortuousness of the small veins and capillaries, are regularly present. The kidney lesion, therefore, is only one of a number of lesions, all dependent on a common mechanical cause.

SYMPTOMS.--Of the persons who die with chronic congestion of the kidney, a large number present marked symptoms during life, but it is difficult to determine how largely these symptoms are due to the congestion of the kidney.

A congestion of the kidney of only a few days' duration does not seem usually to give rise to any symptoms. Even if such a congestion is prolonged to two or three weeks, as we see in some cases of hydro-pneumothorax from perforation of the lung, there may be no renal symptoms and no changes in the urine. On the other hand, it is extremely rare for organic heart disease or emphysema of the lungs to prove fatal without some disease of the kidneys.

The question is still further complicated by the fact that both in cardiac disease and emphysema there may be either chronic congestion of the kidney or chronic diffuse nephritis with the same symptoms.

After excluding the cases of cardiac hypertrophy secondary to kidney disease and the cardiac diseases with complications, I find in my casebooks 137 cases in which the patients died simply from heart disease, changes in the viscera due to the disturbance of the venous circulation, and kidney disease. Of these cases, 84 presented the lesions of chronic diffuse nephritis; 53 were in the state of chronic congestion. Of the cases of chronic diffuse nephritis, 27 were large white kidneys, 29 atrophied kidneys, 28 could not be classed as either large white or atrophied. In these cases there existed during life certain regular symptoms. There were changes in the urine, dropsy, headache, delirium, convulsions, coma, dyspnoea, vomiting, cough, hæmoptysis, loss of flesh and strength.

As regards the quantity of the urine, there was a very great variety until shortly before the patient's death; then the urine was usually diminished in amount, sometimes suppressed. A very marked decrease in the amount of urine was more constant in the cases of chronic diffuse nephritis than in those of chronic congestion. But in several cases both of chronic diffuse nephritis and of chronic congestion the patients passed from thirty to forty ounces of urine up to the time of their deaths.

Albumen and casts were often present--nearly always with the large white kidneys, not nearly as constantly with atrophied kidneys or with {71} the cases of chronic congestion. In cases of chronic congestion the albumen was usually in small amount and often not accompanied with casts.

The specific gravity of the urine was apt to be low with chronic diffuse nephritis and high with chronic congestion, but there were many exceptions to this rule. With large white kidneys, atrophied kidneys, simple diffuse nephritis, and chronic congestion the specific gravity might be either normal, high, or low up to the time of death.

Transudation of the serum into the subcutaneous connective tissue and the serous cavities was a very constant symptom. It was a little more constant, and perhaps usually reached a greater degree, in the cases of chronic diffuse nephritis than in those of chronic congestion.

Headache, delirium, convulsions, and coma occurred in a moderate number of all the cases.

Dyspnoea was a very frequent symptom in all the cases.

Vomiting was also present in many cases.

Cough, with mucus or muco-purulent sputa, sometimes with hæmoptysis, was a very common symptom.

Many of the patients lost flesh and strength and became anæmic.

COURSE OF THE DISEASE.--There is a great deal of similarity in the histories of patients who suffer from the combination of cardiac and renal disease. There is first the history of the heart disease. A patient goes on for a number of years, sometimes apparently perfectly well and unconscious that his heart is diseased, sometimes more or less troubled with cough, cardiac dyspnoea, and palpitation. But after a longer or shorter time there is a marked change for the worse. Either gradually or rapidly the cough becomes worse, the dyspnoea greater, the functions of the stomach are disturbed, the patient loses flesh and strength, dropsy is developed, and finally cerebral symptoms. Some die suddenly, some with exhaustion, some with dropsy, some with dyspnoea, some comatose. It is always possible for the patient to recover from the first attack of this kind, sometimes even from a second, but eventually there comes an attack which proves fatal.

The most striking cases are those in which cardiac disease exists for many years without giving any symptoms, and then the symptoms are developed rapidly. Such persons, although they have organic disease of the heart, may seem to enjoy perfect health. They may even be able to take long walks, climb mountains, or perform laborious work. On some day they suddenly become sick. Sometimes the exciting cause of the attack is a pleurisy or a pericarditis, sometimes there is no apparent cause. The first symptom is usually dyspnoea, and this is not an ordinary cardiac dyspnoea. It is a very distressing and constant dyspnoea, which does not allow the patients to lie down. They pass days and nights sitting in a chair, fatigued, ready to sleep, but kept awake by the constant dyspnoea. Some of these patients will die at the end of a few days; others live longer and develop dropsy, anæmia, and cerebral symptoms.

When the chronic congestion of the kidneys is secondary to emphysema of the lungs, the course of affairs is much the same. The patient goes on for a number of years with the ordinary symptoms of emphysema, and then gradually or suddenly becomes worse. Dyspnoea, dropsy, {72} anæmia, cerebral symptoms make their appearance, and the case terminates in the same way as the cardiac cases.

DURATION.--How long congestion of the kidneys may exist without producing symptoms it is hard to say. Certainly it may exist for a number of days without any apparent disturbance of the functions of the kidney. Whether it may exist for a time, give symptoms, and then disappear, is uncertain; the rule seems to be that the lesion, when once well established, persists up to the death of the patient.

TREATMENT.--It must be acknowledged that we can hardly hope for a cure of the lesion of the kidneys, and that even alleviation of the symptoms is not always possible. The mechanical cause of the obstruction to the venous circulation cannot be removed, and it is not only the functions of the kidneys that are disturbed, but those of the lungs, liver, spleen, stomach, and small intestine. Still, we can do something. The iodide of potassium, convallaria, caffeine, and digitalis may be of service in equalizing and strengthening the heart's action, and at the same time act as diuretics. Inhalations of the nitrite of amyl dilate the arteries and capillaries, and so unload the veins. Opium is the great remedy for the dyspnoea, although it must be given with caution. Inhalations of ether may render the patient's last days more comfortable.

BRIGHT'S DISEASE OF THE KIDNEYS.

After considering separately the condition of chronic congestion of the kidney, we find that there are a group of kidney diseases characterized by certain rational symptoms, changes in the urine, and alterations in the structure of the kidneys which are popularly known by the name of Bright's disease.

Various attempts have been made to classify these cases.

1. All the kidney lesions have been supposed to correspond to the stages of an inflammatory process--a stage of congestion, a second stage of exudation, and a third stage of contraction.

2. The disease has been divided, according to its clinical symptoms, simply into acute and chronic Bright's disease.

3. The gross appearances have been taken as a standard, and the cases are classed as examples of large white kidney, atrophied kidney, waxy kidney, etc.

4. The kidneys have been compared to mucous membranes, and authors speak of catarrhal and croupous nephritis.

5. The disease has been classified, according to the particular part of the kidney affected, into parenchymatous, tubular, glomerular, interstitial, and diffuse nephritis.

With our present knowledge of the subject it seems to me most convenient to speak of acute and chronic parenchymatous nephritis and acute and chronic diffuse nephritis. I include under the head of parenchymatous nephritis all those kidneys in which the lesions are strictly confined to the epithelial cells lining the tubules and the capsules of the {73} glomeruli; under the head of diffuse nephritis, those kidneys in which the lesions involve the tubes, stroma, glomeruli, and arteries; under the head of interstitial nephritis, those kidneys in which the essential morbid changes are in the stroma.

This classification seems to me to be theoretically correct, but yet I must admit that from a clinical standpoint nearly all the cases may be conveniently arranged into the two classes of acute and chronic Bright's disease.

GENERAL SYMPTOMS OF BRIGHT'S DISEASE.--There are a certain number of symptoms common to all the varieties of Bright's disease, and it is convenient to consider them before going on to the special description of each of these varieties. These symptoms are--

Changes in the Urine.--Healthy adults usually secrete during the twenty-four hours from 40 to 50 ounces of urine of a light-yellow color, of acid reaction, of a specific gravity of 1015 to 1025, and holding in solution a number of excrementitious substances. Small amounts of albumen and of sugar seem to be, in some persons, physiological ingredients of the urine.

In most cases of Bright's disease the quantity of the urine at some time in the course of the disease deviates from the normal standard. Either the urine is increased in amount or diminished or suppressed, and in the course of the same case the urine may be at one time increased, at another diminished.

We find in healthy persons that the quantity of urine varies with the amount of fluids that are imbibed and with the condition of the skin and the bowels--that nervous influences and certain drugs will increase or diminish the amount of urine. Physiologists teach us that the amount of urine excreted varies with the degree of the blood-pressure in the renal arteries or with the rapidity with which the blood circulates through these arteries.

The urine may be very much increased or diminished in amount as the result of various morbid conditions. Scanty urine or suppression of urine is observed in the course of acute parenchymatous and acute diffuse nephritis and in the early stages of the development of the large white kidney. During the course of any case of chronic Bright's disease there are usually periods during which the urine is scanty or suppressed, especially toward the close of the disease. The kidney lesions which complicate scarlet fever, yellow fever, and cholera are often attended with suppression of urine. Any diseases accompanied by a well-marked rise of temperature are apt to be associated with a diminution in the amount of urine. Injuries to the urethra, even very slight ones, may be followed by complete suppression of urine, without any changes in the kidneys except congestion.

Marked diminution in the amount of urine occurring in the course of acute and chronic Bright's disease is usually associated with the development of cerebral symptoms--headache, restlessness, delirium, muscular twitchings, convulsions, stupor, and coma. Such a change in the amount of the urine usually lasts only a few days and may terminate fatally, or the quantity of urine will increase and the patient get better. There are, however, cases in which the suppression of urine lasts for several days without the development of uræmic symptoms. Whitelaw[1] relates a {74} case of suppression of urine lasting for twenty-five days in a boy eight years old. The suppression began twelve weeks after an attack of scarlatina. There were no uræmic symptoms, and the child recovered completely.

[Footnote 1: _Lancet_, September, 1877.]

The suppression of urine due to injuries of the urethra gives rise to symptoms of great prostration--rigors, vomiting, and collapse--rather than to uræmic symptoms.

Suppression of urine is also produced by occlusion of the ureters by calculi, new growths, etc. It is a curious fact that in these cases the patients continue to live for a number of days (9 to 11, Roberts), and no uræmic symptoms are developed until a few hours before death.

The most marked examples of persistent increase in the quantity of urine are afforded by cases of diabetes mellitus and diabetes insipidus. But a daily excretion of from 70 to 100 ounces is common enough with atrophied kidneys, with large white kidneys, and with waxy kidneys.

It is exceedingly difficult to form any rational idea of the causes of the variations in the amount of urine in the course of the same case, and in different cases with similar kidney lesions. Various explanations have been attempted, ascribing these changes to the hypertrophy of the left ventricle of the heart, to changes in blood-pressure, to lesions of the arteries, to changes in the composition of the blood, to lesions in particular portions of the kidneys. But any one who tries to apply these explanations to any number of actual cases will find many difficulties.

The most evident causes of diminution in the amount of urine seem to be an abnormal condition of the circulation of the blood and either congestion or structural changes of the kidneys.

The specific gravity of the urine varies from day to day and from hour to hour in the same person, having a regular relation to the quantity of urine passed. But a long-continued deviation from the normal specific gravity is usually an evidence of disease. The highest specific gravities obtain with saccharine diabetes. Abnormally high specific gravities also often occur in the urine of patients with a high temperature, with chronic congestion of the kidneys, and in some cases of acute and chronic parenchymatous nephritis.

Low specific gravities are the rule in diabetes insipidus and with acute and chronic diffuse nephritis. In chronic diffuse nephritis the specific gravity remains low even if the quantity of urine passed is very small. When there is almost suppression of urine from occlusion of the ureters the urine that is passed is of low specific gravity.

These changes in specific gravity correspond of course to the amount of solid matter in solution in the urine, and may depend upon a change in the relative proportion of the fluid and solid constituents of the urine, or upon an absolute increase or decrease of the solid portions.

Any change in the absolute amount of solid matter excreted in the urine must depend upon changes in the composition of the blood, or in the circulation of the blood through the kidneys, or in the structure of the kidneys themselves. All these three conditions seem to exist in Bright's disease, and either together or separately may diminish the daily excretion of solid matter.

It is not necessary here to enumerate the different solid constituents of {75} the urine. A change in the amount of many of them merely indicates disorders of the digestive process. Urea seems to be the most important of the excretory substances, and its quantity is regularly diminished both in acute and chronic Bright's disease.

Blood is found in the urine in a considerable number of cases of Bright's disease. If it is present in large quantities, the urine will be of a reddish color; if in smaller quantities, of a smoky color; and if in still smaller quantities, the color will not be changed. Blood is found regularly with acute diffuse nephritis, with the more severe cases of acute parenchymatous nephritis, with the exacerbations of chronic diffuse nephritis, and with suppurative nephritis. The blood seems to be derived from the tufts of vessels in the Malpighian bodies.

Albumen in the urine is a very common symptom of renal disease, but it is not confined to such cases. It is also found without any structural lesions of the kidneys.

1. There are some individuals whose urine, for many years, will contain small quantities of albumen, and yet their general health is good and they never develop any renal symptoms. In some of these cases the urine is always somewhat diminished in quantity, and in some there is also a little sugar in the urine.

2. In a large number of perfectly healthy persons small amounts of albumen will appear as a temporary condition after muscular exercise, sea-bathing, eating certain kinds of food, etc.

3. Albumen may be present in considerable amount for weeks or months in the urine of young persons, and then disappear altogether. The general health may continue good or be somewhat depreciated. After a time the albumen disappears and the patients have no further trouble.

4. General convulsions, concussion of the brain, and transfusion of blood often produce a temporary albuminuria.

Some observers believe that albumen is always present in the urine, but in such small amounts as to elude the ordinary tests.

Both physiological and pathological albuminuria is most constant and abundant after eating.

The albumen is not all of the same character. Most of it is serum-albumen, but with it is a smaller amount of globulin and sometimes of peptones. As yet the serum-albumen seems to be of the principal practical importance.

Pathological albuminuria is most constant and the albumen is most abundant with acute and chronic parenchymatous nephritis, with acute diffuse nephritis, and with the large white variety of chronic diffuse nephritis. It is least constant and least abundant with the atrophic variety of chronic diffuse nephritis, with some waxy kidneys, with interstitial nephritis, and with chronic congestion of the kidney. A variety of explanations have been given to account for the production of albumen by diseased kidneys, but none of them are very satisfactory.

The albuminuria has been ascribed to disease of the epithelium of the Malpighian bodies; to increase of the blood-pressure within the renal arteries, either with or without disease of the arterial walls; to slowing of the blood-current in the arteries; to diminution of the blood-pressure in the arteries; to congestion of the renal veins; to changes in the {76} composition of the blood; to changes in the epithelium of the renal tubules.

For practical purposes it is to be remembered that large amounts of albumen regularly indicate structural changes in the kidneys; that small amounts of albumen are found without any kidney lesions, with chronic congestion of the kidney, and with chronic diffuse nephritis; that chronic diffuse nephritis may exist without albuminuria for a long time.

In many cases of kidney disease we find in the urine bodies of cylindrical shape called casts. The same bodies are also found within the tubules of diseased kidneys. Concerning the nature and origin of these bodies we are still ignorant. We only know that they are formed within the kidney tubules and are carried thence into the urine. With the exception of the blood-casts, which are composed simply of a number of blood-globules pressed together, all casts seem to be formed of a peculiar homogeneous hyaline substance to which other elements may be added. Hyaline casts are composed entirely of such material. Waxy casts are formed of the same substance, which becomes denser. Epithelial casts are made by the adhesion of epithelial cells to the surface of hyaline casts. Nucleated, granular, and fatty casts are hyaline casts with the fragments of degenerated epithelium incorporated in them.

Occasionally hyaline casts are found in the urine of healthy persons. They also occur as a temporary condition after severe muscular exertion, with typhlitis, with renal calculi, and with jaundice. Most frequently, however, they are associated with structural disease of the kidneys. Usually they are found in albuminous urine, and in proportion to the amount of albumen, but we may find casts without albumen and albumen without casts.

With chronic congestion of the kidney the casts are hyaline and few in number. With acute parenchymatous nephritis there are hyaline, granular, nucleated, and epithelial casts. With chronic parenchymatous nephritis there are hyaline, granular, and nucleated casts. With acute diffuse nephritis there are blood, epithelial, hyaline, granular, nucleated, and fatty casts. With chronic diffuse nephritis there are hyaline, waxy, granular, fatty, nucleated, and epithelial casts.

An accumulation of serum in the subcutaneous connective tissue, in the serous cavities, and in the lungs is one of the regular symptoms of Bright's disease. It usually appears first in the feet or in the face. Such dropsy is said to be due to a low specific gravity of the blood-serum; to the loss of albumen; to the scanty elimination of urine; to hydræmia plethora; or to changes in the walls of the blood-vessels.

The functions of the stomach are often disordered, either with or without the existence of chronic gastritis. Loss of appetite, nausea and vomiting, oppression after eating, etc. continue and grow worse throughout the disease. Vomiting is also a frequent concomitant of the so-called uræmic attacks.

Diarrhoea often occurs with dropsy and a scanty excretion of urine, and may then be of service to the patient, but it sometimes becomes very profuse, rebellious to treatment, and is of positive injury.

Dyspnoea associated with Bright's disease seems to occur in several different ways. It may be of mechanical origin from oedema of the lungs or from hydrothorax. It may be a purely nervous phenomenon, {77} or it may depend upon a complicating heart lesion. The nervous dyspnoea seems to be allied to the uræmic vomiting and cerebral symptoms; it is often most distressing.

In the course of chronic Bright's disease disturbances of vision occur dependent on three different conditions: (1) There may be a loss of vision, usually temporary, without any discoverable lesion of the eye. (2) There may be simple neuro-retinitis. (3) There may be the characteristic nephritic retinitis with hemorrhages and fatty degeneration of the retina. These two forms of retinitis are often the first symptoms of renal disease.

Neuralgic pains, most frequently referred to some part of the head or face, but also to other parts of the body, are prominent symptoms in some cases.

The Blood.--Both in acute and chronic Bright's disease the patients often become markedly anæmic and pale. This change in the color of the patient corresponds to an alteration of the composition of the blood with the details of which we are not as yet fully acquainted. The blood seems to be thinner and more watery.

Cerebral Symptoms.--Headache, drowsiness, stupor, sleeplessness, delirium, coma, muscular twitchings, and general convulsions are of frequent occurrence. The headache and drowsiness may continue during the course of the disease for many months. The stupor, sleeplessness, delirium, coma, muscular twitchings, and general convulsions are apt to occur in attacks which last for several days, and then pass away or terminate in the death of the patient. With such cerebral symptoms are often associated dyspnoea, vomiting, increased temperature, and diminution in the excretion of urine. The entire group of symptoms is commonly known by the name of uræmia.

It is a matter of great practical importance to determine the cause of these cerebral symptoms, for otherwise there can be no rational treatment of them. It is evident that such cerebral symptoms must depend upon anatomical changes in the brain or its membranes, or upon a change in the composition of the blood which circulates through the brain, or upon the quantity of blood supplied to the brain.

It is to be remembered that such cerebral symptoms occur most frequently with the atrophic form of chronic diffuse nephritis; that they are often the first symptom of renal disease; that the same person may have several such attacks, with no cerebral symptoms during the interval; that the urine is usually, but not always, diminished during the attack, and becomes more abundant when the attack ceases; that such attacks also occur with the chronic congestion of the kidney due to cardiac disease, in pregnant women without kidney disease, and with diseased arteries and high arterial tension without kidney disease.

Anatomical changes in the brain or its membranes do exist in a considerable number of cases of chronic Bright's disease. Chronic meningitis with thickening of the pia mater and an increase of serum is quite common; anæmia and oedema of the brain-tissue are often seen. But there are a great many cases with cerebral symptoms without such lesions, and with such lesions without cerebral symptoms.

The composition of the blood is undoubtedly changed in most of the cases with cerebral symptoms. It is natural to look for such changes as {78} are due to perversion of the excretory function of the kidneys, and to ascribe the cerebral symptoms to the poisoning of the blood by urea, by urea transformed into carbonate of ammonia, or by the other excretory matters which should be eliminated by the urine. Moreover, it has been demonstrated that there is a very marked increase in the amount of urea contained in the blood in such cases. On the other hand, we find that suppression of urine with accumulation of urea in the blood may exist for a long time without cerebral symptoms if the suppression is due to obstruction of the ureters; that with chronic congestion of the kidney, puerperal convulsions, and diseased arteries urea is excreted in fair amount, although cerebral symptoms exist; and that even in cases of cerebral symptoms with chronic diffuse nephritis there may be no increase of urea in the blood.

In most of the cases with cerebral symptoms, however, there are other changes in the composition of the blood, concerning the exact nature of which we are still ignorant. In most cases of chronic Bright's disease the patients become pale and the blood is thin and watery; and this is also often the case with chronic congestion of the kidney and with diseased arteries. In pregnancy the quantity of blood is said to be increased: in cholera a considerable part of the fluid portions of the blood is lost.

Changes in the amount of blood in the brain may be due to lesions of the cerebral arteries or to contraction of these arteries; to changes in the arteries in other parts of the body; to organic disease or functional disorder of the heart; or to a change in the whole amount of blood contained in the body.

It seems to me probable that the so-called uræmic symptoms are most frequently due to disturbances of the circulation of blood. Such disturbances of the circulation produce in the brain cerebral symptoms; in the lungs, dyspnoea; in the stomach, vomiting; in the kidneys, suppression of urine.

With the atrophic form of chronic diffuse nephritis we have all the conditions necessary for an irregular circulation--hypertrophy of the left ventricle, diseased arteries, and hydræmic plethora. In the other cases with cerebral symptoms there are also conditions present capable of interfering with the circulation.

Acute Parenchymatous Nephritis.

PATHOLOGICAL ANATOMY.--The lesions of acute parenchymatous nephritis vary with the intensity of the inflammatory process.

(1) Mild Cases.--The kidneys are of normal size and weight. The capsules are not adherent, the surface of the kidney is smooth, the cortex is of normal color or rather pale. The epithelial cells lining the convoluted tubes are swollen and granular.

(2) More Severe Cases.--The kidneys are increased in size. The cortex is thick and whitish, with white striæ extending in to the bases of the pyramids. The epithelium of both the convoluted and straight tubes and of the Malpighian bodies is swollen and granular. There is cast matter in the tubes. {79}

(3) The Most Severe Cases.--The increase in the size of the kidneys is still more marked. The epithelium of most of the tubes is not only swollen and granular, but is also in many tubes detached from their walls. A great deal of cast-matter, and sometimes blood, is found in the tubes. There are no changes in the stroma or in the blood-vessels of the kidneys.

ETIOLOGY.--Acute parenchymatous nephritis occurs both as a primary and secondary lesion. The idiopathic cases occur without assignable cause or after exposure to cold, and are not very common. The secondary cases are seen very frequently. They complicate a variety of other diseases. With pneumonia, typhus fever, and typhoid fever the nephritis is usually of mild type. With yellow fever and acute atrophy of the liver the nephritis is very severe. With scarlatina, diphtheria, pyæmia, peritonitis, phosphorus- and arsenic-poisoning the severity of the nephritis varies with the different cases.

SYMPTOMS.--(1) The Idiopathic Cases.--The urine is diminished in quantity and may be suppressed; its specific gravity continues nearly normal; it contains albumen, usually in large amounts, sometimes blood: in some cases very few casts are seen, in others there are large numbers of hyaline, granular, and nucleated casts.

As regards the other symptoms, it is convenient to divide the idiopathic cases into three classes. In the first class dropsy and anæmia are the most marked symptoms; with these there are loss of appetite and a depreciation in the general condition of the patient. In the second class cerebral symptoms are more prominent. There will be delirium, convulsions, stupor, coma, and with these persistent vomiting, dyspnoea, and great prostration, but no dropsy. The third class suffer from the symptoms of both the other classes. Dropsy, anæmia, loss of appetite, cerebral symptoms, vomiting, dyspnoea, and prostration are all present.

(2) The Secondary Cases.--The condition of the urine varies with the intensity of the nephritis. In the mild cases the urine is unchanged. In the more severe cases we find the urine diminished in quantity, containing albumen in varying amount, sometimes blood. Hyaline and granular casts are often present, but are not very numerous. Dropsy does not usually occur except with the parenchymatous nephritis of scarlatina. Nausea and vomiting are not infrequent, but it is often difficult to tell whether they are due to the primary disease or to the nephritis. Cerebral symptoms--convulsions, delirium, stupor, and coma--occur with the more severe cases.

DURATION.--(1) The Primary Cases.--The class of cases characterized by cerebral symptoms are of short duration. The bad cases die at the end of a few days, the milder cases recover within a few weeks. The class of cases characterized by dropsy last longer, often for several months.

(2) The Secondary Cases.--The renal symptoms continue during the course of the primary disease, and may disappear with the termination of this disease. But if the nephritis is severe the renal symptoms may continue for months after the primary disease has run its course. Albumen and casts are especially apt to persist for a long time. Such a persistence of the nephritis is especially apt to occur with scarlatina and diphtheria.

{80} PROGNOSIS.--(1) The Primary Cases.--The cases characterized by both dropsy and cerebral symptoms usually end fatally. The cases characterized by cerebral symptoms alone are also very apt to die. The cases characterized by dropsy and anæmia often get well, but the albumen and casts may persist for a long time, and the patient may have several attacks of such a nephritis.

(2) The Secondary Cases.--Here the prognosis varies with the intensity of the nephritis. The more severe forms of the inflammation may add very much to the danger of the primary disease or may persist for a long time afterward.