XXII. Diseases of the Kidneys.

Renal Hyperemia.

So intricate is the minute anatomical construction of the kidneys, and so abundant is its capillary and nerve distribution, that any influence to which the nervous and circulatory systems are susceptible is apt to immediately disturb the circulation within the kidneye and produce changes in the functional operations of these organs—in the elimination which is so essential in ridding the system of the effete matter—and these changes are manifest in most cases in the quantity, quality and the character of the urine.

Active Hyperemia.

Synonyms:—Acute renal congestion; acute renal hyperemia.

Definition:—An engorgement of the capillary circulation within the kidneys, resulting in immediate alteration of function.

Etiology:—The condition is due to the action of sudden cold, or to the conditions which influence transpiration through the skin and other emunctories; to the influence of stimulating diuretics and other irritating medicines, which must be eliminated through the kidneys, but which exercise an irritating or injurious influence upon the minute structure of the malpighian tufts or upon the renal epithelium. It follows also the ingestion of toxins and the effort of the system to rid itself of toxins due to direct infection. Scarlet fever, diphtheria, septicemia and typhoid fever occasionally induce active renal hyperemia.

The condition is also induced by traumatism, either direct or remote, by surgical operations, especially laparotomies and those upon the bladder and urethra. It occurs as a result of anesthesia.

Symptomatology:—There may be for some days an aching sensation in the loins, which steadily increases to dull pain of a heavy, dragging character, which is often very distressing. This may be accompanied with chilliness, malaise, indisposition to physical exercise, and a slight elevation of the temperature. At first there is an abundant secretion of urine of reduced specific gravity, but this stage is so transient that it is often overlooked; a condition of scanty urine of dark color and high specific gravity, occasionally precipitating urates when cooled, is first observed. When the irritating cause is direct in its action, there may be sharp pain in the kidneys, with some blood in the urine, and perhaps tube casts. In extreme toxemia, the congestion may be so immediate and profound as to cause complete suppression, but usually a small quantity of very albuminous urine, which may contain blood coloring matter or blood debris, with abundant corpuscles and tube casts, is secreted. There is anorexia, general muscular aching, some vertigo, nausea and increasing debility.

Diagnosis:—The extreme backache, which often seems to radiate toward the stomach, producing faintness and nausea, with a sudden change in the urine from a previously normal condition to that which is scanty, high colored and albuminous, will determine the condition.

Prognosis:—In ordinary cases the prognosis is favorable. Where irritating poisons have been taken, or where septicemia is the cause, the prognosis must be guarded.

Treatment:—The most accessible, rational, physiological and successful treatment is the application of persistent heat. However, I have often applied dry cups, six or eight in number, over the lumbar region for from eight to ten minutes before applying the heat. A towel should be folded and wrung out of hot water containing a little salt. This should be applied and a hot water bag applied over it. At the same time the patient should have a thorough irrigation of the colon with hot water, and the hot normal salt solution should be then injected. The patient should be kept warm in bed and a mild perspiration should be sustained. Great care must be taken that no irritating diuretics are administered. Belladonna in sufficient doses is the rational remedy at the onset. Gelsemium exercises a most important influence, and hydrangia is of much value. These may be given in a hot infusion of epigea repens or of marshmallow with good advantage.

If the pulse is sharp, hard and quick, aconite will control the temperature and will be of benefit in inducing free action from the skin.

Active hyperemia seldom occurs independent of other symptoms. In addition to the treatment suggested it will be necessary to meet the indications of the other conditions in the most prompt and direct manner.

Passive Hyperemia.

Definition:—Chronic or passive congestion of the kidneys designates a chronic condition of engorgement of comparatively slow development, depending usually upon faults of the circulation which result from deficient or imperfect heart action.

Etiology:—Not only are chronic heart disorders to blame for chronic renal engorgement, but the condition may result also from chronic diseases of the lungs, pleura, liver, or from chronic disease of the kidneys themselves. It may occur also during the course of an aortic aneurism, or from thrombosis of the ascending vena cava, or thrombosis of the renal vein, or from the presence of tumors or other abnormal growths, or from ascites. It is not uncommon during pregnancy, from the pressure of the gravid uterus.

Symptomatology:—The constitutional evidences are those of general failure and anemia. There are dropsical symptoms, which may be at first local, but are subsequently general. There is a sensation of weight and dragging in the loins, with perhaps some pain, which may extend down into the thighs. There is a scanty secretion of urine with a high specific gravity, usually containing an appreciable quantity of blood with blood casts, as well as hyaline and tube casts. Albumin is present, usually in small quantities. Blood is often present in large quantity, precipitating as a dark, heavy, or brown sediment. There will be found present in nearly all cases chronic disease of the heart, with valvular lesion. There may also be hepatic disorder, quite apparent, or chronic gastric disorder, as well as chronic disease of the kidneys, which this condition usually accompanies.

Diagnosis:—Passive hyperemia must be distinguished from chronic Bright's disease by the exclusion of the classic symptoms of that disorder. The fact that there is usually but little albumin present in chronic hyperemia will assist in excluding a diagnosis of parenchymatous nephritis. In interstitial nephritis there is but little albumin, but there is a large quantity of water and the urine is of low specific gravity, while in this condition there is but little water with a specific gravity of from 1,024 to 1,032. If this condition persists, it may ultimately develop a typical case of chronic nephritis.

Prognosis:—As the prognosis depends upon the cause, and the cause is usually a somewhat serious intractable disorder, the prognosis must be guarded. If chronic organic disease is not discoverable, the prognosis is favorable.

Treatment:—The treatment will be general rather than symptomatic; the stomach and nervous system must be put into the best possible condition by the use of carefully selected tonics; heart remedies should be selected with reference to the exact condition of the heart; if any dropsical effusion is apparent, apocynum will be available. If the condition of the heart seems to be associated with serious gastric disorder, I should combine cactus and hydrastis, as I have observed excellent results from these remedies. To these may be added avena sativa, as a stimulating tonic to the nervous system. The liver must be regulated with iris, leptandra, chionanthus or the sodium phosphate. Podophyllum will seldom be needed.

Where constipation is persistent, fifteen grains of the magnesium sulphate may be given, either alone or with fifteen grains of the potassium tartrate, four or five times a day. In cases where there is increasing dropsical effusion, a full dose of the sulphate of magnesium should be given each morning, or each alternate morning. Where debility and anemia are pronounced, Professor Whitford gives from five to ten grains of the carbonate of iron in conjunction with this salt, and believes that further debility from the cathartic action of this remedy is prevented.

Much attention should be paid to the diet. Strongly nutritious but easily digestible foods should be selected. I have given these patients from one to six raw eggs each day and had them drink freely of skimmed milk. Fruit in season may be permitted, and baked potatoes and juicy lean beef are acceptable.

The Eclectic Practice of Medicine with especial reference to the Treatment of Disease, 1910, was written by Finley Ellingwood, M.D.