A uretero-pelvic junction (UPJ) obstruction is a blockage where the ureter (the tube that carries urine from the kidneys to the bladder) connects to the renal pelvis (the central collecting part of the kidney). This obstruction occurs when there is a blockage or narrowing at the point where the ureter meets the renal pelvis.
The renal pelvis collects urine produced by the kidneys before it flows down the ureter into the bladder. If there's an obstruction at the UPJ, urine cannot flow freely from the kidney to the bladder. This can lead to a buildup of urine in the renal pelvis and the kidney. The blocked urine flow can cause the renal pelvis and the kidney to become dilated, a condition called hydronephrosis. This can potentially lead to kidney damage if not treated promptly.
Patients with UPJ obstruction may experience intermittent or constant pain in the flank (the side of the body between the ribs and hip) due to the pressure buildup in the kidney. Stagnant urine in the renal pelvis can increase the risk of urinary tract infections (UTIs) and kidney infections.Urine stasis can also contribute to the formation of kidney stones. Over time the blocked kidney can lose kidney function from the obstruction.
The causes of UPJ obstruction can vary. It may be congenital (present at birth) due to abnormal development of the area, or it can develop later in life due to factors such as scarring, inflammation, or compression caused by other structures.
Treatment options depend on the severity of the obstruction and the symptoms. Mild cases might only require close monitoring, while more severe cases could necessitate surgical intervention. Common surgical approaches include pyeloplasty, which involves removing the obstructed area to restore normal urine flow. A pyeloplasty is most often done robotically. The choice of treatment depends on the patient's overall health, the extent of the obstruction, and other individual factors.
