Fetal posterior urethral valves (PUV) is a congenital defect in males that results in obstruction of the bladder due to extra tissue that projects into the urethra. This excess tissue blocks urine from flowing freely from the bladder to the outside of the body. This blockage, if not corrected, can cause problems in all the organs in the urinary system including the kidneys, ureters, urethra and bladder. Depending on the extent of blockage, the organs can swell, causing damage to the tissues and cells within those organs.
Fetal PUV can be diagnosed by ultrasound (sonogram) examination before birth. Evaluation of the urinary system is part of the routine ultrasound examination done by many obstetricians as part of their routine prenatal care around the 20th week of pregnancy. If the doctor finds on the ultrasound that the baby's bladder is swelling and there is a decrease in the amount of amniotic fluid, this may be a sign that the baby is suffering from this condition.
In the most extreme cases, infants may be treated before they are born. A small catheter or shunt is passed through the mother's abdomen into the womb and into the baby's bladder to drain the blockage. Newborns who undergo this procedure need additional treatment after they are born; the type of treatment depends on the severity of the blockage. In the most severe cases, newborns need immediate emergency treatment. To relieve the obstruction and allow elimination of the urine, a catheter is inserted. After the baby is stabilized, a minimally invasive procedure is performed to remove the excess tissue and valvular structures that are causing the blockage. Sometimes more extensive surgery is necessary. It is important to correct the blockage, if possible before damage to the other organs has occurred.
After the fetal PUV is treated, children are evaluated for other problems that the blockage may have caused. Children are followed carefully, but the outlook for normal urinary function is very good in mild cases. Some boys may continue to experience urinary incontinence, frequency, and urgency and may need further treatment to remedy these symptoms.