the action of the toxins; or, on the other hand, a myocarditis may arise following primary renal disease.

In summarizing, uremia may be defined as—a series of manifestations, chiefly nervous, developing in the course of Bright's disease, and probably due to the retention or presence, in the blood, of certain poisonous materials that most likely result from the abnormal action of degenerated renal cells. This is in substance the definition proposed by Osler.

Diagnosis. In well-developed, typical cases of uremia, when a complete history of the case in question is available, the diagnosis is easy. In its milder manifestations, when the symptoms are but slightly developed, the diagnosis is difficult and often impossible. A history of headache, edema, and particularly of a diminution, especially very recent, in the amount of urine excreted, is of the greatest importance. When the disease is fully developed, such symptoms as vomiting, stertorous breathing, coma or somnolence, less frequently maniacal symptoms, associated with increased blood pressure, hypertrophy of the heart, particularly of the left ventricle, and, perhaps most important of all, diminution in the amount of urine excreted, together with the appearance in it of albumin, casts, renal epithelium, and probably blood, leave little doubt as to the diagnosis. Nevertheless, circumstances may arise, even in the most typical case, that will greatly complicate and confuse the diagnosis.

Perhaps one of the most characteristic manifestations of uremia, and one which permits its differentiation, in the majority of cases, from diseases manifesting similar symptoms, is the variability of its clinical aspects. The pulse, which in the ordinary case is hard, full, and bounding, may within a few hours become soft and feeble, to be followed again, perhaps, by a return of the high pressure. The occurrence and disappearance of edema, when present, is an important differential sign.

There is no one feature of the disease that is of greater value, and at the same time occasionally more misleading, than the condition of the urine. In typical cases the amount of urine, and the percentage of urea in particular, is considerably diminished; on the other hand, some cases, especially those occurring in chronic nephritis, are particularly likely to be associated with polyuria.

Still more rarely the urine may be normal in amount, in chemic content, and casts and epithelium may be entirely absent. Repeated examinations will usually, however, eventually corroborate the existence of nephritis. The differentiation is partic ularly difficult when albuminuria or a true nephritis occurs at the onset of an acute infectious disease, the picture of which may closely simulate uremia. As a rule, the temperature-curve in any of the acute infections is more or less characteristic, and the presence of a leukocytosis aids materially in the differential diagnosis. In typhoid, hypoleukocytosis, mononuclear increase, and the presence of the Widal reaction make differentiation certain. Miliary tuberculosis, particularly where early involvement of the cerebral meninges takes place, is often distinguished with much difficulty, and frequently a differentiation is impossible until definite tubercular lesions can be demonstrated, as in the retina, or until pleurisy or peritonitis develops. The differentiation from septicemia associated with albuminuria may be possible only when metastatic suppuration can be demonstrated.

Uremia is differentiated with particular difficulty from true focal lesions of the brain, as in embolism, hemorrhage, or meningitis. The character of the pulse is identical in many conditions, and when, as is so often the case, nephritis preëxisted, differentiation may be impossible. This is particularly true in cerebral hemorrhage. In nearly all these conditions a positive diagnosis can be reached only when, as almost always happens in uremia, the picture of the paralysis suddenly changes. There is almost invariably a certain incoherence of symptoms when the case is under careful observation, but when seen for the first time, an absolute diagnosis is impossible. In this relation it is well to remember that cerebral embolism and cerebral hemorrhage sometimes occur in uremia, a fact amply demonstrated in a series of postmortems performed by the writers. The ophthalmic examination is often of great differential value, since the presence of albuminuric retinitis, in the absence of definite urinary manifestations, may decide the point in question.

The condition is very commonly confused, particularly in hospital and city practice, with various forms of poisoning. This is perhaps most true of alcoholism. Here the history of the case is

of the greatest importance. The examination of the urine and the presence or absence of alcoholic tremor may also often make differentiation possible. As a rule, besides, the delirium of alcoholism is of a more active type than is that of uremia. In this regard, however, it must be remembered that uremia occurs as a common terminal condition in alcoholism, as has been demonstrated to the writers by a close study of the material derived from the alcoholic wards of Bellevue Hospital. Opium-poisoning is distinguished with even greater difficulty than alcoholism, when the urine does not present characteristic findings. Ptomainpoisoning and other similar conditions are often confused with uremia, and their distinction may demand a most careful study of the entire course of the disease before a positive diagnosis can be arrived at.

Prognosis. The prognosis in uremia is dependent on the degree of disease that exists, on the length of time it has been present, on the promptness with which treatment is begun, and on the reaction of the patient to this treatment. It also depends largely on the condition of the general organs of the body, and on the readiness with which the underlying condition responds to treatment. In general, the writers believe that the prognosis is more favorable than is commonly supposed. The mild manifestations, such as headache, decrease in the amount of urine voided, symptoms of early cortical irritation, edema, and the like can usually be relieved; and when subsequent treatment, associated with a careful control of the diet, exercise, and general habits of life, is possible, the prognosis is good. In those cases in which the response to medication is not prompt, the prognosis is generally bad. In any case recurrence, particularly when extra strain is imposed upon the kidneys, may take place; and, although a uremic patient may be restored to comparative health, subsequent attacks are likely to develop at almost any time, the second or third generally terminating fatally.

Treatment. The cardinal feature in the treatment of uremia should be the stimulation of secondary excretion. The bowels should be freely opened, and oftentimes the most drastic agents are necessary for this purpose. Elaterium, in doses of one-sixth of a grain, is highly recommended; croton oil, in doses of from

one to three minims, repeated until the stools become watery, is also useful. The action of the skin is to be stimulated by the use of hot packs and the administration of pilocarpin, preferably intramuscularly or hypodermatically, in doses of about one-eighth of a grain; when edema lessens the absorptive powers of the skin, it should be given by the mouth. When the condition of the heart is unfavorable, pilocarpin is to be used with care. When the pulse is hard and bounding, one of the most efficient measures, in the writers' experience, is the removal of a quantity of blood and the substitution of saline solution. When necessary, strychnin and digitalin should be employed to support the heart action, and vasodilators should be used freely when the blood-pressure is high. Of the latter, nitroglycerin, in frequent and large doses, is to be recommended for its immediate action, but more permanent benefit has been secured from the use of chloral, as recommended by Peabody, Thompson, and others, the drug being given preferably by the rectum in doses of from 30 to 45 grains. Chloral, in our experience, is one of our most reliable vasodilators.

If convulsions are present, they are to be relieved by chloral and bromids, given preferably by the rectum and in large doses. Urethane has been highly recommended by Peabody for this purpose, but the writers are not sufficiently familiar with it to attest its value. It may be necessary in some cases to employ chloroform for the relief of convulsions, but, except where immediate relief was demanded, chloral has proved much more satisfactory in the writers' hands. When the condition of the patient permits, water may be given in large quantities, or saline enemata or transfusions may be used when the patient is unconscious.

The after-treatment is that of chronic Bright's disease, attention being paid particularly to the diet and to the habits of life, as detailed under the proper heading. It should constantly be borne in mind that in the treatment of uremia promptness is of the greatest importance, and when one measure fails to act, others should be employed in its stead.

CHAPTER XI

TUBERCULOSIS OF THE KIDNEY.-THE KIDNEY IN

SYPHILIS

TUBERCULOSIS OF THE KIDNEY

There is probably no other diseased condition of the urinary tract concerning which our knowledge is in a more confused state, particularly as regards prognosis, than it is in respect to tuberculosis of the kidney.

Pathology. Renal tuberculosis occurs as a not infrequent condition or complication in cases of miliary or generalized tuberculosis. Horst Oertel, pathologist to the City Hospital, reports that, of the seven cases showing renal tuberculosis which came to autopsy at the City Hospital in the year 1904, five complicated the pulmonary disease. In four of the seven cases both organs were involved. Our personal statistics vary somewhat from these in significance, since most of our cases except those of a clearly terminal character have originated independent of detectable pulmonary lesions, but were associated with tubercular lymphadenitis or with a primary tuberculosis of the lower urinary tract. Differing from the ordinary general condition, tuberculosis of the kidney as seen in the primary disease of the genito-urinary tract is often found to be monolateral, and clinical observation has convinced us that it may, when properly supervised, remain so for long periods, provided that secondary infection of the bladder or urethra does not take place. A sharp distinction must therefore be made between those cases in which renal tuberculosis arises as a terminal complication in a practically hopeless case of tuberculosis, and where it originates in, and remains chiefly limited to, the urinary organs. Joseph Walsh' found renal tuberculosis present in 43 per cent. of 101 consecutive cases of fatal pulmonary tuberculosis. In practically all these cases, however, in 1 Third Annual Report, Phipps Institute.