CHRONIC UR-EMIA usually develops gradually, and may not be recognized at once, although the pathognomonic list lessness and indifference of manner in cases of Bright's disease becomes some what more marked. The movements be come slower, and speech is somewhat in distinct. Dimness of vision, tinnitus aurium, and uneasy feeling in the head or, mayhaps, violent and persistent head ache may be present. The symptoms oc casionally improve or disappear, but they uniformly recur, and gradually become more intense. The drowsiness passes into stupor. When the patient is roused to speak, articulation is at first thick and indistinct, and, later, the patient cannot be made to respond; stupor deepens into coma; the breathing assumes that char acteristic stertor before mentioned; and death ensues. Exceptionally, the pa tients may suffer from a noisy delirium, in which prolonged howling alternates with muttering or with paroxysms of ex citement; there may be low prolonged muttering, with a repetition of the same word or phrase. Subsultus tendinum and twitching of the facial muscles are cum monly seen throughout. Convulsions, diarrhoea, and vomiting are frequently present. Epistaxis may occur, but is rare.
In chronic uremia, says Delafield, the convulsions, sudden coma, dyspncea, high temperature, aphasia, hemiplegia, and contractions of the arteries are absent. The action of the heart and pulse are feeble. The patients pass into a condi tion of great prostration, with alternating delirium and stupor. The fatal termina tion in cases of chronic Bright's disease is commonly by this form of urmmia. It may occur, as an exception, in the early stage of the inflammatory form.
Diagnosis. — Acute comatose uraemia may closely resemble cerebral apoplexy with loss of consciousness, but may be distinguished from it by the absence of unilateral paralysis, the character of the breathing, pulse, and heart-action, and the condition of the urine.
Acute convulsive uraemia may resemble epilepsy, but it usually lacks the initial cry, the death-like pallor, the predom inance of unilateral convulsions, the in turning of the thumbs upon the palms, and the loss of reflex irritability. The urine, after an epileptic seizure, may re veal the presence of albumin and a dimi nution of urea, but it soon returns to a normal condition; in uraemia it is always distinctly albuminous. The condition of the pupils and the examination of the urine will distinguish this condition from poisoning by opium or belladonna.
Chronic uraemia, when fairly estab lished, is usually recognized without dif ficulty. An examination of the urine furnishes the most valuable evidence. Chronic uraemia may sometimes resemble fever or meningitis, from which it may be differentiated by the history of the ill ness, the condition of the urine, the tem perature, breathing, and weak pulse and heart-action. Pepper calls our attention to certain cases which develop gradually and pass into a typical typhoid state which cases are met most frequently at or after middle life and in connection with chronic interstitial nephritis. The facial expression and mental state are curiously like those of typhoid fever; a low grade of fever with bronchial and gastrointes tinal catarrh is not unusual. The detec tion of arteriosclerosis and cardiac hyper trophy and albuminuria with casts; the odor of the breath; the absence of erup tion, epistaxis, and splenic enlargement; and the history and course of the case will serve to establish a diagnosis.
Etiology.—The etiology of uraemia is not definitely known. Francis Delafield says that contraction of the arteries (a condition existing in acute uraemia} causes the involuntary contraction of groups of muscles, general convulsions, stupor, coma, dyspncea, labored heart action, hypertrophy of the left ventricle of the heart, blindness, aphasia, hemi plegia, a high temperature, and, perhaps, dropsy. Acute uraemia is often developed in nephritis while the specific gravity of the urine is still good, and the quantity of the urine is not diminished until after the contraction of the arteries is established. There can be no reason, therefore, to be lieve, says Delafield, that the contraction of the arteries is due to contamination of the blood by excrementitious substances, and we must frankly admit that the reason of the contraction is yet unknown. We know, however, from a wide experi ence, he adds, that when by the use or drugs we can dilate the arteries, the symptoms dependent upon their contrac tion will disappear. Chronic uraemia is developed in persons who are passing little or no urine, or urine of low specific gravity, and is evidently caused by the contamination of the blood by excre mentitious substances.