RECOVERY OF RENAL FUNCTION IN UNILATERAL NON-VISUALIZING KIDNEY OBSTRUCTED BY A URETERAL STONE

Abstract

Recovery of renal function and irreversible damage in the kidney after release of obstruction by means of renography, intravenous pyelography and histological examination, were observed in the eleven cases with unilateral non-visualizing kidney obstructed by a ureteral stone.
The results were as follows:
1) Return to normal renal function was noticed if the duration of obstruction was less than a month. But return on function was delayed and irreversible damage was resulted if the duration of obstruction was longer than two months.
2) On intravenous pyelogram, normal urogram was observed within a year in the cases whose obstructed duration was less than two months. But renal atrophy gradually progressed even after removal of obstruction.
3) The irreversible changes in obstructed kidney was mainly intimal fibrous thickening of distal renal arterys with narrowing of lumen. As soon as these arterial organic damages developed, the return to normal renal function could not be assesed though the high interarenal pressure fell by removal of obstruction and some improvement on renal function could be obtained by increased on renal blood flow.
4) Six patients with unilateral obstructed kidney developed hypertension (over 90mmHg on lower pressure). Hypertension was cured after release of obstruction or nephrectomy of obstructed kidney on them. We think this reduction of the blood pressure was attributed to improvement on renal blood flow but it was transient on the case with the irreversible changes in obstructed kidney.
5) One of the hypertensive patients was presented with the lumenal stenosis due to segmental fibro-muscular hyperplasia at the main renal artery in the obstructed kidney. His hypertension was immediately cured by removal of the obstructed kidney.