Is a distended renal pelvis congenital, or can it have another cause? i am 53 and it is only recently discovered after hysterectomy

See below: A distended renal pelvis can indicate obstruction of urine flow from the kidney into the ureter. This can be due a congenital malformation called upj obstruction, but can also be due to other blockages such as a stricture or stone in the ureter, or from extrinsic compression of ureter from something else. Then again, it can just be a redundant renal pelvis that is not blocked. See a urologist.