Chronic Interstitial Nephritis.
Synonyms:—Contracted kidney; small, red kidney; granular kidney; renal sclerosis; sclerotic kidney; cirrhosis of the kidney; chronic Bright's disease; chronic non-exudative nephritis.
Definition:—A chronic inflammation of the kidneys, diffuse in character, involving degeneration of the parenchyma, a growth of new connective tissue and atrophy.
Etiology:—This disease occurs after middle life, is of long duration, and occurs most commonly in males, probably owing to their more careless habits of living, dissipation, the contraction of specific disease, and more violent physical exercise. It is of unknown origin in many cases, both as to cause and to time, as it may undoubtedly exist in the incipient or developing stage for a number pf years before it is positively diagnosed. The following of occupations in which there is a continued absorption of substances into the system which in being eliminated must keep up a continued although perhaps mild irritation of the kidneys, is thought to be the cause of the disease, such as chronic lead poisoning, chronic phosphorus poisoning, and as specified, the persistent use of alcohol. Another cause is probably the lifelong habit of excessive eating and drinking, in which undue activity of tissue metabolism and elimination is necessary in ridding the system of the persistent excess of food and drink. The same conditions from imperfect metabolism may be the cause of continued autointoxication. The persistent eating of large quantities of meat and excessive coffee drinking will establish a uric acid diathesis, which, when accompanied with a habit of drinking but little water, will cause a permanent irritability of the renal structure, which will frequently result in sclerosis or granular atrophy.
It is thought that heredity exercises considerable influence in the causation of this disease, as it has occurred in the males of three or four generations. But it is more than likely that similar careless, injurious or dissolute habits of living were transmitted and in each case may have been the inducing cause. Conditions which induce degeneration of the arteries lead also to interstitial nephritis.
A close relationship has been known to exist between gout and rheumatism and this form of kidney disease. Those patients who are inured to mental labor, who worry at their responsibilities and are inclined to anger or excessive grief will be apt to exhibit the characteristic symptoms late in life.
Symptomatology:—When a man above fifty years of age, who has been a high liver, and has persistently labored under undue nervous excitement, or with extreme nervous tension, during his entire business career, without being obliged to yield from disability, finds himself easily fatigued or overwrought, devoid of his usual energy and vivacity, with a disinclination to engage in anything that demands activity or mental concentration, it is well to examine the urine for the early symotoms of this disease.
For a period of several years following this there may be but few evidences of renal disorder. The patient will observe that he is drinking a large quantity of water and passing water freely, but the urine may not be distinctively pathologic. However, the specific gravity is usually less than 1,010; the urine is pale, but there is no great diminution in the amount of solids excreted. During the earlier stages the quantity of albumin found, if any, will be very small, and it will be with difficulty and persistence that an occasional tube cast is found. Often no albumin is looked for, but the condition is diagnosed as a mild form of diabetes insipidus, resulting from brain tire, which, it is thought, will disappear as soon as relaxation and rest will permit. The patient will rise two or three times in the night to urinate, but will continue to claim that he never felt better in his life. A peculiarity of this excess of urine is that it is distinctly acid in its reaction, although perhaps a gallon is being passed within twenty-four hours, and there is some frequency and difficulty in urinating, and some local discomfort or lack of propulsive force, which will be found to be due to irritation of the prostate, which may be somewhat enlarged. When there is atrophy of the glomerules there may be no albumin present in the urine; later there will be less difficulty in discovering casts, and perhaps some leucocytes will be found.
If the digestive apparatus and the nervous tone remain intact, the patient may continue in this condition until old age approaches, but with increasing inability to plan or execute either mental or physical labor. There is no dropsy usually, until a short time before a fatal termination. Then it will be observed that there is a decreasing quantity of urine and an increased quantity of albumin and casts, although there is no great increase in the specific gravity. Nervous symptoms will appear, the prostatic difficulty increases, and there may be a slight cystitis, when, quite suddenly, dropsy develops, uremic symptoms appear quite rapidly, and there are other evidences of rapid failure.
I have observed this abrupt change in symptoms to be brought on by some sudden disability of the gastrointestinal tract, as an acute attack of dyspepsia, with a consequent failure to appropriate sufficient nutrition. If symptoms of gastritis are present, with loss of appetite, the symptoms of nephritis are much more conspicuous. I am confident that the stomach should have immediate attention when these conditions occur, until they are entirely relieved. Severe vomiting or sharp attacks of diarrhea may occur, which are evidences of the accumulation of toxins or of a uremic condition. These may abate later, to recur when excretion is imperfect.
In the later stages of this disease there is always more or less uremic intoxication, though if the elimination be free, this may not be apparent, but when free elimination is interfered with there will be headache, nausea, vomiting or diarrhea, as I have just stated, with faults of vision, mental dulness and increased frequency of urination. Prompt attention to the elimination will result in recovery from these symptoms, with perhaps no evidences recurring for months, when another attack will appear which will be more severe than the previous one. Uremic dyspnea is a distressing symptom, which is sometimes quite intractable, and may precede an attack of convulsions. It can be distinguished from cardiac dyspnea, except in those cases in which there is valvular disease or cardiac hypertrophy. In these cases the apex beat will be found below the normal point and to the left; the beat will be heaving in character and of increased force, A mitral systolic murmur is occasionally observed; the pulse is usually slower than normal, is hard and resisting to the touch, large, round and full; in the final stage of collapse it becomes irregular or feeble, small, soft and compressible. The dyspnea in the earliest stages usually occurs at night; in the final stage, whether it is uremic or cardiac, it is constant, and as mental dulness or stupor increases the breathing may assume the Cheyne-Stokes type.
These patients suffer much from insomnia. Headache, as has been stated, is a common symptom, and is not amenable to the usual remedies. It may be intermittent or simply remittent, the exacerbations being at some times extreme, the headache assuming a bursting character, with some mild delirium. If any structural change in the arterial coats is present, apoplexy may occur at such a time. In parturient cases the headache is the precursor of the convulsions, and sometimes the only premonitory symptom. The apoplectic attack may be mild, inducing temporary coma, with some local peripheral paralysis, or it may induce a hemiplegia and be sufficiently severe to result in death. If recovered from, a recurrence may be anticipated of increased severity.
The occurrence of shooting pains in the deep muscles is a common symptom in all forms of albuminuria. I have known it to be the persistent symptom, which has induced the patient to consult the physician for rheumatism, in the diagnosis of which the real condition was discovered. These pains may be accompanied with cramps, especially in the calves of the legs. The skin is dry and harsh, and when it is peculiarly pale or chalky in appearance it will be found that more or less edema is present from cardiac dilatation or other heart faults, as renal sclerosis does not result in edema until the final stage. Pruritis is a common symptom, with acne or minute pustules, and occasionally eczema will be found present.
The appearance of the retina is a strong diagnostic factor in this disease. It has been found that twenty-two per cent of patients suffering from albuminuria exhibit lesions of the retina. Albuminuric retinitis, exhibited in four or five different forms, is recognized by ophthalmologists. Retinal hemorrhage, which may be small and circumscribed or profuse and extensive, is common. Uremic amaurosis may occur, which may be at first only temporary, but finally becomes permanent. When the diffused blood is absorbed, the underlying area becomes whitish in color. Tinnitus aurium, with more or less permanent deafness, and vertigo, may be present in these cases.
Diagnosis:—As has been stated, a positive diagnosis may be almost impossible in the early stage of this disease, and even in cases where there is but little doubt that the disease is of three or four years' duration it is difficult to determine whether the symptoms which are attributable to this disease may not be due to other existing conditions, which on their part may in reality be due to the presence of this condition. The age of the patient, his previous habits and health must be considered, and parenchymatous nephritis excluded.
The pathognomonic phenomena of a well developed case are in some particulars the opposite of those of the parenchymatous form. There is a large quantity of colorless or pale urine, which is often described as lactescent or milklike. It has a low specific gravity, is of slightly acid reaction, is passed very frequently, both day and night, without pain, and contains no blood or pus and but a very small quantity of albumin. The presence of tube casts is confirmatory, but these are difficult to find in so large a quantity of water. The erratic headaches, the retinal faults, the occasional attacks of dyspnea, with pruritis and frequent nose bleed, are all suspicious indications. If with these there is persistent mental dulness, delirium or coma, which usually follow the sudden anoearance of free dropsical effusion, the diagnosis is confirmed. The heart symptoms are of but little benefit in diagnosis, as they are in every way similar to those that appear in other diseases of the organ.
Prognosis:—While no known method of cure for this disease has as yet been discovered, life may be prolonged for a number of years, some patients living to a ripe old age. Others are attacked with acute disorder, from which they may die, or an accident may terminate the life. I have made it a habit to base a prognosis upon the integrity of the stomach and digestive apparatus. This I do in part for its moral effect upon the patient. I lay it down as an inviolable rule that the patient must not forget at any meal the importance of eating slowly and thoroughly masticating the food, never overloading the stomach, and eating only those articles of diet which are permitted. A sudden termination of the disease may be precipitated by apoplexy and consequent paralysis, or by convulsions, or by heart failure from overstrain. Exposure to causes which suddenly arrest the secretions, causing immediate increase in uremia and increased blood pressure, contribute to this.
Treatment:—The treatment of these cases is largely hygienic. If the patient can be made to appreciate the situation and the importance of watching his own condition and guarding against excesses, he will do much more than the physician toward prolonging his life. Having its origin, as it does, at that time of life when a man's mental faculties are in the best possible condition, a reasonable man may be persuaded to fully appreciate the situation and lay out for himself a plan of life which will prolong his days to ripe old age.
The nervous system must be restored to its normal condition, and all nerve strain, undue excitement, responsibility, anger or worry must be avoided. Regular times must be set aside for recreation, and the mind must be freed at those times from everything that demands concentration or mental absorption. A well selected nerve tonic will contribute to a restoration of these organs. That which is of almost equal importance I have twice referred to because to me it has so important a bearing on the outcome of the case, and that is the retaining of the integrity of the stomach and digestive apparatus. Whenever a slight digestive dis-tubance appears, it should have immediate attention, and the patient should be acquainted with the different action of the different artificial digestives, so that he may be enabled at times to select one for the particular purpose to which it is especially adapted at that time. A generous diet, with sufficient nitrogenous elements, is required. The patient may eat a reasonable quantity of fresh meat, rare. Cured meats are objectionable. Eggs, cream and milk are permissible, and for short periods it will be found to be well to keep the patient upon an exclusive milk diet, but if this be too long continued, the patient will lose in strength and vital force. Fruits and cereals may be eaten freely; sweet potatoes and baked potatoes are permissible, but coarse vegetables should be avoided. Coffee and cocoa, with all alcoholic drinks, should be interdicted.
During the progress of any gastric disorder the food must be selected with care, must be eaten slowly and thoroughly masticated, and the digestion must be assisted either by prepeptonizing agents or by artificial digestives. The observations of the patient concerning the various foods and their reception by the stomach must be utilized by the physician in selecting the articles of diet.
Physical exercise is important, but it should not be overdone and should be taken in the open air. For this reason it is desirable that the patient should make his permanent residence in a warm, dry climate, with dry soil and with an abundance of sunshine, as the changeability and dampness of the cooler climates tend to increase this disorder.
But very little can be accomplished with medicines depended upon to exercise a direct influence upon the pathological elements of this disease. In the earlier stages each condition must be treated according to its own indications, and when a fairly normal condition of health is obtained, medicines should be avoided. Emergency treatment is often demanded in the latter stages. The uremia should always be antagonized; for this purpose free elimination from the bowels and skin must be maintained, constipation must be prevented, and rational measures adopted to procure daily normal bowel movements. Free normal transpiration from the skin should be encouraged, but the sweat glands should not be persistently overstimulated, as a reaction is apt to occur, with permanent functional inactivity and dry skin. The normal action of the heart should be maintained, and everything avoided that increases arterial tension. Normal tension is important. Insufficient arterial tension may result in dropsy.
I have much confidence in the prolonged use of echinacea in antagonizing the development of uremia, with proper measures to retain the number and integrity of the red blood corpuscles. This agent will antagonize the presence and development of toxins. Gelsemium preserves a freedom from nervous irritation, both in the nerve centers and in the renal organs, and consequently is valuable in its influence upon the heart, relieving the tension and promoting cardiac tranquillity. Minute does of nitroglycerine should be advised for short periods, only when the tension is too high, and strychnin, cactus, digitalis or avena should be given when it is too low. Uremic manifestations must be overcome by a temporary stimulation of all the eliminative organs, with the object of throwing off as large an amount as possible of the toxic principles. While echinacea is a valuable alterative, there are certain conditions of the blood in this disease which are best met with iodin in the form of the sodium, strontium or potassium iodid. This is especially true when there is a syphilitic taint in the blood or other dyscrasia. The first two act favorably upon the stomach also, while the potassium iodid, although a gastric irritant, reduces muscular irritability, and will thus be of benefit in decreasing undue arterial tonus. Apocynum will increase the power of the heart, and when dropsy results from imperfect heart action this will be found to be the most available remedy. Cerebral complications must be met in accordance with their indications. The bromids and ergot will abridge the hemorrhage or prevent it when threatened. Strychnin in properly selected doses will antagonize paralysis. Convulsions should be treated as suggested in acute nephritis. For this purpose veratrum will be found the most satisfactory remedy. I am confident that single doses of as much as one dram may be given in sthenic cases hypodermically with only good results. Three or four doses of twenty minims each, repeated every half hour or hour, will usually be as efficient and devoid of danger. Morphin must be avoided, as it complicates the kidney trouble, and by locking up the secretions materially increases the uremia. It is directly contraindicated.
During the progress of this disease, and especially during its later stages, complicating disorders are apt to arise, which must be treated, each according to its specific indications and with more care and positiveness than if occurring alone.
The Eclectic Practice of Medicine with especial reference to the Treatment of Disease, 1910, was written by Finley Ellingwood, M.D.