Treatment.

—Such cases as the above may even perplex the surgeon, since they complicate many other surgical conditions. Yet if they go no farther than above described they are to be treated rather by internal methods, i. e., diluents, with hot-air baths, and especially by urotropin, the remedy of greatest value, while such drugs as aspirin, benzosol, sodium benzoate and the like, in moderate doses and at rather short intervals, may be administered to great advantage.

Renal Abscess; Surgical Kidney.

—The conditions above described do not necessarily nor often terminate with resolution. Not infrequently suppuration follows, with resultant abscesses, which may be solitary and possibly large, but are more likely to appear in multiple and perhaps punctate form. Should this condition occur in one kidney alone, it determines probably its ultimate destruction; if in both kidneys, the prognosis is very grave, since later, if not immediately, such a case will succumb to renal failure, due to the extra load put upon the portion still capable of secreting. It is to kidneys thus crippled by acute or subacute infections, with punctate abscess and similar lesions, that in the past the term “surgical kidney” was applied, because such kidneys were seen oftener in surgical than in so-called medical cases.

Brewer has recently called attention to a type of acute hematogenous renal infection, to which he has given an identity of its own. The possibility of renal infection through the blood has been long recognized, but it has been generally supposed to produce bilateral lesions. Of late, however, it has been shown that these may be unilateral, on account of the diminished resistance of one kidney as the result of previous disease or injury, among the former being calculus, renal retention, and floating kidney. While the colon bacilli are most frequently at fault the infection is often of the pyogenic or mixed type. It seems to be more frequent in women than in men. The symptoms are those of an acute infection, often ushered in by a chill, with sudden rise of temperature, sometimes followed by such marked remission as possibly to suggest malaria. The pulse ranges high. Abdominal pain is an almost constant symptom, although it is usually vague and often shifting or referred. Sometimes it will cause such a complaint as to lead to mistaken diagnosis in favor of an acute appendicitis. Occasionally it radiates along the course of the ureter. Tenderness in the costovertebral angle is nearly always present. Muscle rigidity is frequent but inconstant. There is nearly always a leukocytosis, with a percentage of about eighty polynuclears. Frequency of urination may accompany these cases, but they will ordinarily be diagnosticated by physical and urinary examination. The urine will usually contain albumin, perhaps with pus, and occasionally a few red blood cells. Urine obtained from the affected kidney by ureteral catheterization will contain more of these evidences of abscess than that from the other side. Brewer has had far better success in entirely removing the affected kidney than in exposing and simply draining it. He has thus done a great service in demonstrating the possibility of unilateral acute and suppurative disease of the kidney, where diagnosis is most obscure and the clinical picture one of acute general abscess rather than of local affection, showing as well that the more acute cases tend rapidly to terminate fatally unless promptly arrested by complete removal of the affected organ.

As we consider the above infections, with others yet to be mentioned, it becomes more necessary to appreciate those constituents and characteristics of the urine which have for the surgeon the greatest significance, and those methods of investigation which furnish him the promptest and most satisfactory results.

The following include methods in present use for determining renal capacity and function, i. e., the matters of greatest importance:

1. By cystoscopy, with ureteral catheterization, we determine whether urine is secreted by both kidneys or but one, while the secretion of each kidney may be separately collected and studied. Even this method leaves much to be desired. Though one kidney be actively diseased it may still contain sufficient tissue to make it partly competent for its purpose, and undesirable to remove; or an organ with very defective structure may, nevertheless, yield a certain amount of nearly normal urine. These, then, are aids to determine the character of the morbid process, and the information they furnish is valuable, but not always sufficient.

2. Cryoscopy, based upon the physiochemical law that the freezing point of the solution is proportionate to the number of molecules it contains, i. e., to its molecular concentration, has revealed that the blood of a person with severe kidney lesion freezes at a lower temperature, while the freezing point of his urine would be much higher than in a normal individual, because those materials which should have been excreted in the urine are, on account of impaired renal function, retained in the blood and do not get into the urine. The freezing point of normal urine varies from -0.09° to -2.3° C.; the freezing point of normal blood from -0.55° to -0.57° C. The reasoning employed in the method is sound, but the method itself difficult, requiring special apparatus and experience. Moreover, the limits of the possibility of error are such that this method alone should never be relied on. It is essentially a test of the ability of the kidneys to act as filters, but does not test their serviceability as secretory organs.