This is where the top end of the tube that drains urine from the kidney (ureter) is blocked, hence not allowing urine to drain out of the kidney.
It can be present at birth (congenital) or come about as an adult (acquired).
It is commonly unilateral.
Symptoms
PUJ obstruction may not cause any symptoms and are found accidentally when scans are done for other reasons. When they do cause symptoms they include
Intermittent pain in the back after drinking large volumes of fluid or alcohol
Frequent UTIs
Stone formation
Causes Of PUJ Obstruction
Causes of PUJ obstruction can be congenital or acquired.
Congenital causes include:
Abnormal muscle arrangement at PUJ
Persistent fold in ureter
Persistent blood vessel to the kidney causing compression of the PUJ (crossing vessel)
Acquired causes include:
Obstructing stone
Infection causing scarring
Cancer of ureter
Diagnosis
Diagnosis requires 2 forms of imaging
CT scan
This will show a dilated kidney and define the anatomy. It is also useful for checking for crossing vessles.
MAG-3 Scan
This will assess the function of the kidney and check if the kidney is truly blocked or not.
Treatment
Treatment depends on underlying cause. Since in the majority of cases a benign cause is identified surgical correction with a procedure called pyeloplasty is done.