HYDRONEPHROSIS.
Hydronephrosis is a term applied to the dilatation which the pelvis and calyces of the kidney undergo by the pressure of the urine when the latter is prevented escaping in a natural manner into the bladder. It is as if a band were gradually drawn round the ureter while the excretion by the kidney continued. Hence the term indicates a varia ble state of distention and the implication of one or both organs in the process. When extreme it may result in the absorption by pres sure of the entire excreting portion of the gland and the ultimate con version of the kidney into a fibrous bag containing fluid, of which the capsule and the septa are the boundaries. When the process is limited to one kidney, the opposite organ often proves equal to meet ing the requirements for the entire excretion of urine, but the con dition obviously becomes extremely serious when both kidneys are implicated in the cause upon which the hydronephrosis primarily depends.
With such a definition before us it will not be very difficult to recognize the various circumstances under which one or both ureters may be subjected to a degree of pressure sufficient to bring about such changes in the kidney. In the first place, we have evidence that hydronephrosis is sometimes the result of congenital defects in the ducts. Folds, twists, valves, and obliquities in the mode of entering the bladder, in the ureters have been found explanatory of this effect. In a case recorded by Sir William Roberts in his treatise on " Urinary and Renal Diseases," the pressure of an anom alous branch of a renal artery appeared sufficient to cause it. Various malformations in the course of the ureters and their rela tions with the kidneys have also been described as associated with hydronephrosis.
The accidental causes of ureteral obstruction are equally various. In an analysis of 142 cases of hydronephrosis Morris mentions nu merous causes for interference with the descent of the urine into the bladder, of which cancer involving parts within the pelvis appears to be the most frequent. Cystitis, vesical calculus, villous growth of the bladder, enlarged prostate, hydatid and ovarian cysts are also enu merated. Out of these 142 cases which include various degrees of
hydronephrosis 106 seem to have implicated, more or less, both kid neys. Dr. L. Landau' has drawn attention to some cases of intermit ting hydronephrosis observed in women, which he connects with a twisting or "kinking" of the ureter belonging to the kidney involved. The symptoms in some degree resembled those of renal colic con nected with stone, and were accompanied with tumefaction of a vary ing character in the region of the kidney. In two of the instances re corded the symptoms disappeared during pregnancy—a circumstance which was explained by the movable kidney being fixed in position by the gravid uterus. In one case relief was afforded by an abdom inal bandage. It is in cases such as this that well-directed massage temporarily removes both swelling and pain. Then we have lesions and injuries to the ureters which chiefly affect one side only; of these I may mention stones impacted in the ducts and contractions, or strictures, resulting from injuries to these tubes.
In 1883 I was consulted by a gentleman from South America about an injury he had received in the right loin from a bullock on a cattle ranch. The injury was not attended with an external wound, but there was a severe contusion of the part; it was followed by hmma turia, and more remotely by right hydronephrosis, for which aspira tion had been repeatedly employed. The point raised was, if the ureter is merely strictured, and not completely ruptured, can any thing be attempted to save the kidne' from atrophy? As it seemed probable the ureter had been divided, and the corresponding kidney was rapidly being atrophied, I came to the conclusion that it was ad visable that nothing should be done, and I have since heard the patient has completely recovered his health, though there can be no doubt he has lost a kidney.
The following case, recorded by Mr. W. J. Collins in a paper on traumatic by is of much interest in connection with the diagnosis and treatment of these injuries :