Dr ( Prof.) Anant Kumar - Urologist | Kidney Transplant Surgeon is regarded as the best and most experienced Kidney Transplant Surgeon of India and Director-Urology,Kidney Transplantation and Robotics at Max Hospital,Saket,New Delhi,India.

What is Uretero-pelvic junction Obstruction?

Uretero-pelvic junction obstruction occurs when the flow of urine from the renal pelvis to proximal ureter have an obstruction. The condition may lead to Hydronephrosis. Hydronephrosis is a medical condition ,where the kidneys are swollen with urine because of narrowing or blocking of ureters. Ureters empty the urine from kidneys into urinary bladder. The resultant back pressure within the renal pelvis may cause progressive kidney damage or deterioration of kidney function.

Uretero-pelvic junction obstruction may appear in children due to a congenital abnormality or even in adults following any previous surgery or any other medical condition that causes inflammation of upper urinary tract.

What causes pediatrics UPJ Obstruction ?

The exact cause of pediatrics uretro pelvic junction obstruction is still not known. Many times the defect is present in an unborn baby and is termed as congenital defect. It is diagnosed during routine prenatal ultrasound.

There may be many reasons for UPJ obstruction during the gestation period. some of them are:

• During the developing phase the child's ureter is not fully formed resulting in a narrowed section of ureter which may be blocked later on.
• A faulty muscle in ureter wall which may not squeeze normally.
• Formation of a "Crossing Vessel" ,i.e., an additional artery feeding the kidney of developing fetus. This may result in kinking or blocking of the ureter.

It can have a genetic component,i.e., it runs in families .Although the responsible gene is not identified yet.

What are symptoms for pediatrics UPJ Obstruction?

Sometimes a UPJ Obstruction in a child does not have any symptoms. A UPJ Obstruction in a developing fetus is usually observed during a routine prenatal ultrasound. It is detected because of hydronephrosis. In majority of cases it is corrected on its own after the child birth.

But in moderate to severe condition the following symptoms may occur and they do need a medical attention as if left untreated,it may cause a permanent damage to kidney or urinary system of child.

• The renal pelvis or kidneys or both are dilated (hydronephrosis).
• Abdominal,back or flank ( sides) pain.
• Frequent UTIs ( Urinary tract infections).
• Edema
• Swelling around eyes.
• Lump in abdomen ( Abdominal mass).
• Poor or retarded growth in infants.
• Fever.
• Rashes.
• vomitting.
• Bloody urine or diarrhea.
• Abnormal urine output.

How UPJ Obstruction is diagnosed?

If Hydronephrosis is observed in a developing fetus during a routine prenatal ultrasound , doctor in charge for delivery of child will do more periodic ultrasound to keep a close vigil on any complications arising of the present medical condition.

Many times this medical condition is resolved on it's own ,once the child is born. But the doctor may do following tests after a few week of birth of child.

• Creatinine clearance.
• BUN ( Blood urea Nitrogen).
• CT Scan.
• Electrolytes.
• CT- Urogram.
• Nuclear scan of Kidneys.
• Voiding cystourethrogram.
• Ultrasound.

What causes UPJ Obstruction in adults?

The reasons for UPJ obstruction in adults may be due to scar tissues,infection,any previous surgery or renal calculi (Kidney Stones).

The other reasons may be:

• A previous renal pelvic trauma.
• Obstructing calculus immediately distal to PUJ.
• Previous pyelitis with scarring.
• Intrinsic malignancy,e.g. upper tract urothelial carcinoma.
• Extrinsic ureter compression due to

1. Fibrosis.

2. Crossing vessel at PUJ.

3.An underlying malignancy.

Symptoms of UPJ Obstruction in adults:

Adults may experience following symptoms because of UPJ Obstruction:

• Renal colic.
• Chronic back pain.
• Other non specific signs may be hematuria,Urinary tract infections and pyelonephritis.

Treatment Options:

Treatment line depends on presence of underlying cause.In Majority of congenital cases,no intervention is required and the condition subsides after some time however in case of a definite structural obstruction ,surgical intervention in the form of pyeloplasty or stenting may be needed.

Surgery is also inevitable in case of deterioration of renal function or when associated symptoms are severe and progressive.Aim of treatment is to normalize renal drainage and if possible,improve if  reversing the damage to kidneys is not possible.