Active Hyperemia.

Synonyms.—Acute or Active Congestion of the Kidney.

Definition.—A temporary congestion of the blood-vessels of the kidneys, attended with little or no exudation.

Etiology.—Acute congestion is caused by the presence of irritants in the blood, either in the form of toxins, which are found in all the infectious as well as some of the other fevers, or by the ingestion of certain drugs, such as turpentine, potassium chlorate, carbolic acid and cantharides, santonin, copaiba, squills, and many others.

Severe injuries to various parts of the body may also give rise to congestion, while severe surgical operations, especially those on the bladder and urethra, or laparotomies, are frequently attended by acute congestion. The removal of one kidney is apt to be followed by congestion of its fellow. Sudden chilling of the body is a very common cause. The simple operation of introducing a catheter into a sensitive urethra may be followed by acute hyperemia of the kidney.

Pathology.—The kidney is swollen, soft, dark-red in color, and if a section is made, the blood flows freely. In very severe congestion, the microscope will reveal cloudy swelling of the cortical substance.

Symptoms.—There is a sense of weight and oppression, rather than acute pain, in the lumbar region. The urine is scanty and, in some cases of poisoning, is almost suppressed. It is of a dark-red color, contains blood-corpuscles, some albumin, and, in severe cases, tube-casts. There may be slight elevation of temperature and an increased pulse-rate.

Diagnosis.—The diagnosis is readily made. Oppression in the lumbar region, scanty and highly colored urine, with normal or but slightly elevated temperature, can hardly be mistaken for any other condition.

Prognosis.—The prognosis is always favorable, save where the result of some major surgical operation.

Treatment.—The old alcohol sweat or spirit vapor-bath is an excellent measure at the beginning of an attack. Continue the bath until there is copious perspiration, when the patient is to be carefully covered in bed and given an infusion of couch grass (triticum repens), haircap moss, or marshmallow. Usually aconite and gelsemium is all that is needed:

Sig. Teaspoonful every hour.

Apis in drop doses is also a valuable remedy. If the bowels be constipated, a full dose of antibilious physic will greatly assist the specific in overcoming the acute congestion.

The Eclectic Practice of Medicine, 1907, was written by Rolla L. Thomas, M. S., M. D.