-PATHOLOGY OF THE KIDNEY.
It will not be possible within the limits of this article to give more than an outline of the pa thology of the kidney. The subject is one of such great interest and importance that it re quires a much more extended consideration than can here be assigned to it.
The diseases of the kidney may be arranged in two distinct classes: the first class including those which are the result of sotne cause acting locally, such as retention of the urine in con sequence of stricture, the mechanical irritation of a stone impacted in the kidney, or a blow on the loins ; while in the second class are in cluded those diseases which are the result of a constitutional cause which acts upon the kidney by inducing an abnormal condition of the blood.
We shall allude very briefly to the first class of diseases, and then proceed to the con sideration of those diseases to which the kid ney is liable in consequence of a deteriorated condition of the blood.
Disease of the kidney from retention of urine. —Fig. 165. represents a condition of the kid ney which commonly results from an im peded escape of the urine. The ureter pelvis and infundibula become much dilated, and the cortical substance expanded and lobular on the surface, the depressions between the lobules resulting from the binding down of the tissue by the interlobular septa, in the intervals of which the glandular structure is protruded by the distending force from within. The mucous membrane frequently becomes ulcerated, inflammatory deposits occur in the substance of the kidney, and so the gland is destroyed by a slow atrophy, or more rapidly by suppurative inflammation. Both kidneys are usually affected, but in different degrees. On a microscopical examination of the kid ney thus diseased, pus and other inflammatory deposits are found. The deposits are not confined to the tubes, but they occur irregu larly throughout the gland, so as in many instances to obliterate all appearance of tubu lar structure.
Disease of the kidney from renal calculi. — When a calculus forms in the kidney, it may lead to very different results according to its size and position. If of small size, it may pass down the ureter and so get into the bladder ; or if it be too large to pass through the ureter, it may, by becoming impacted in the canal, and so obstructing the flow of urine, give rise to a rapidly destructive sup purative inflammation, or it may lead to com plete atrophy of the gland. It sometimes
happens that several calculi become impacted in the pelvis of one or both kidneys, causing ulceration of the surrounding tissue, and leading in some instances to a complete dis organisation of the gland.
Disease of the kidney front external violence— is not of common occurrence. One case of the kind has occurred to myself. A strong man in robust health received a violent blow on the loins from a bludgeon ; he suffered much pain, and within a short time after the receipt of the injury he had hmmaturia. The bleeding recurred at intervals during several months, and was succeeded by a discharge of purulent matter with the urine. The purulent discharge continued for a period of more than a year, when the poor man died much emaci ated. On a post mortem examination, the right kidneywas found completely destroyed by suppurative inflantmation ; there was no stru mous deposit in the kidney or in any other organ. There was no calculus. The left kidney was quite sound.
Extension of disease front other organs to the kidney. —The kidney sometimes becomes in volved in malignant or other disease affect ing the intestines and other adjacent viscera. Allusion has already been made to a prepa ration in the Museum of King's College, in which there is a communication between an abscess in the psoas muscle and the canal of the ureter.
Diseases resulting front a constitutional cause.
—Scrofulous disease of the kidney occurs in the form of small scattered deposits of tuber cular matter, or it presents itself in the form of a thick curdy deposit which leads to the formation of a large scrofulous abscess, the cavity of which is subdivided by septa formed by the thickened interlobular cellular tissue. Cfig. 166.) The scrofulous deposit commonly chronic disease of the kidney, in consequence of the intemperate use of fermented liquors by a man whose general health was much dis ordered, and who had been subject for several months to successive crops of boils and car buncles about the neck and shoulders. He died in about a week after symptoms of sup purative nephritis had manifested themselves. The nature of the disease was detected at the very commencement by a microscopical exa mination of the urine Cfig.167). Both kidney's extends over the mucous membrane of the ureter, which becomes much thickened.