Hydronephrosis

The end result of unrelieved obstruction is a shrunken, scarred, non-functional kidney — this is called hydronephrosis.

What our notes say

The end result of unrelieved obstruction is a shrunken, scarred, non-functional kidney — this is called hydronephrosis. (Urinary Tract Obstruction & Hydronephrosis: Causes, Symptoms)
Hydronephrosis means dilation of the renal pelvis and calyces due to backed-up urine, combined with progressive destruction of kidney tissue. (Urinary Tract Obstruction & Hydronephrosis: Causes, Symptoms)
Local spread obstructs the ureters, causing hydronephrosis and renal failure. (Junior Clerkship in Reproductive Health (MBOG 4200): end of year examination, 4 )
Obstruction at the bladder outlet causes bilateral hydronephrosis and low amniotic fluid (oligohydramnios). (Paediatrics end of fourth year special supplementary exam: August 2019, Paper On)
Complications: acute urinary retention, recurrent UTIs, bladder diverticula, hydronephrosis (Pathology Practical Revision Guide)
Abnormalities of the ureteropelvic junction, which must recanalize, can lead to obstruction with hydronephrosis. (renal pathology — Past Paper Questions & Answers)