CYSTIC EIDNEY, KIDNEY, FIYDRONEPI1ROSIS Cystic degeneration of the kidney is in most eases bilateral. In this condition the kidneys form a system of sacks, separated by areas of normal renal tissue.
In regard to its genesis, there are three opinions:: Virchow believed that the cysts were retention cysts, resulting from obstruction of the urinary ducts, either by uric salts or by fcrtal interstitial nephropa pillitis. Two other theories assume a cyst formation upon an cedeniatous base, or from an arrest of development (Erich Meyer, von Dungern). The organs may be normal in size, or they may become larger than a child's head and interfere with delivery (fcetal giant kidneys, Schenkl).
If there remains a sufficient quantity of active renal parenchyma the affected individual may live for many years; if not, death occurs sooner or later with symptoms of urminia. The clinical course of cys tic kidney may be either — without any- symptoms, or it may assume the aspect of a renal tumor (see Figs. 6-7). Since it is common for the affection to be bilateral, it is i3nportant to investi gate the functional ability of the other kidney before attempting the removal of the eyst by operation.
By the name of tvaler-bng kidney (hydronephrosis) we understand a dilatation of the renal pelvis with consecutive atrophy of the organic parenchyma. It may be either congenital or acquired; unilateral or bilateral. The acquired cases (resulting f r o concretion, from inflamma tory obstruction of the ure ter, from compression of the ureter by tumors filling the abdomen), are probably rarer during infancy than the con genital eases. If they develop acutely, they may cause pain in the thorax and abdomen, vomiting and symptoms of ti ri n a r y intoxication. The causes of the congenital type are anomalies in development of the ureter or of the urethra, which result in stricture of these tubes (atresia of the ureter, abnormal valvu lar formation, congenital plaintosis, etc).
While water-bag kidney is not generally recognized as long as it is small, the larger ones present the appearances of a renal tumor (Fig. 9).
The diagnosis depends upon the demonstration of fluctuation, as well as upon the results of the chemical examination of the fluid which is obtained by puncture. High-grade bilateral hydronephrosis is not compatible with long life. It leads to death by urtemia.
The treatment of unilateral hydronephrosis is surgical. com plication which seriously endangers life, unless surgical intervention is undertaken at the right time, is the infection of the u-ater-bag kidney, either through the blood, or through the ascending tubules, i.e., the formation of a pyonephrosis.
TumoRs OF THE KIDNEY There are a number of benign tumors of tlw kidney (liponi a, fibroma , lipofibroma , pornykofi broma, etc.), which seldom attain a size greater than a walnut, and which do not produce any clinical symptoms, but which may be detected accidentally at autopsy. These same tumors, however, may originate in the renal capsule, may spread over the kidney and the suprarenal gland, and may produce the same clinieal symptoms as the tumors about to be discussed in the following lines.
Amongst the tumors which have clinical importance belongs the hypernephroma (struma suprarenale, Grawitz), which originates from the suprarenal cells, as well as sareorna and carcinoma, which Birch Hirsehfeld grouped together under the name of embryonal gland tumors. Moreover, there arc found mixed tumors, adenosareorna, myxosarcoma, lymphosareoma, sarcoma with enclosed muscular fibres, etc. (see Plate .15S). The malignant renal tumors observed in early life are sup posed to be congenital in origin.
All the statistics show the remarkable fact that the greatest num ber of renal tumors occur in children during the first decade. Steffen compared 219 eases, and found that 34 occurred during the first year, 55 in the second, and that the sum of those occurring during the first five years was 16S out of the 219.