The most common abnormality in the lower urinary tract is the development of obstructive megaureter in children. This condition involves an obstruction at the point where the ureter connects to the urinary bladder. Typically, the diagnosis of obstructive megaureter is made after observing the dilation of the kidney and ureter during a prenatal ultrasound examination.
One of the kidney's functions is to filter various waste products from the blood and excrete them as urine into the urinary bladder. After the kidney filters the waste, urine enters the kidney's collecting system and exits through a structure called the renal pelvis. If there's a risk of impaired kidney function, a child might undergo a kidney mapping test known as a MAG-3 scan. This test, performed at a nuclear medicine institute, involves injecting a minimal amount of radioactive material into the child's bloodstream. The test helps assess the individual kidney's function and how the injected material is cleared from the kidney, aiding in confirming or ruling out urinary obstruction. It's generally considered that normal kidney function is around 50%.
Children with kidney and ureter dilation should undergo a voiding cystourethrogram (VCUG) to rule out reflux, a condition where urine flows from the bladder back into the ureter. This can be an additional cause of kidney and ureter dilation. During this test, a catheter is inserted into the ureter, and a contrast material is injected to visualize the flow of contrast material into the ureter and kidney.
Treatment decisions depend on the severity of the condition. Not all children with kidney and ureter dilation require surgery; fewer than 30% of diagnosed cases necessitate surgical intervention. The Pediatric Urology Department at Sheba Medical Center has been a pioneer in adopting conservative approaches to treat these children, avoiding surgery whenever possible. Currently (as of 2011), over 6,000 children have been monitored in this department for kidney and ureter dilation, and only 25% of them have required surgical correction. Surgical intervention is typically recommended for cases such as deteriorating kidney function during follow-up, infants with reduced kidney function after birth, and those with significant blockage detected through kidney imaging or clinical symptoms like urinary tract infections or abdominal pain.
The Pediatric Urology Department at Sheba Medical Center has extensive experience in treating children with obstructive megaureter. The department has published its innovative techniques in leading pediatric urology journals worldwide and has presented them at numerous international conferences. When surgical correction is deemed necessary, a minimally invasive approach using robotic assistance is preferred, resulting in faster healing, reduced pain medication usage, and improved cosmetic outcomes.
After surgery or conservative treatment, children are monitored through regular ultrasound examinations every 3-6 months, along with periodic kidney mapping scans, to ensure the preservation of kidney function and determine the need for further interventions based on the results of these tests.