Posterior Urethral Valves in Children: Causes, Symptoms, and How It’s Treated

A] What Are Posterior Urethral Valves?

PUV occurs when secondary tissue flaps form in the urethra. These flaps work as a barrier that doesn’t allow the urine to pass freely through the bladder and kidneys. Over time, this accumulates pressure on the urinary system and can cause serious damage, particularly to the kidneys.

This condition is congenital, although the cause is still unknown. It is said to occur at odds during fetal development, but there may be a genetic influence in some instances. PUV only occurs in newborn boys; it is one of the common causes of urinary tract blockages in newborn boys.

The severity of PUV can vary. There are often cases when an infant does not exhibit any signs of a blockage, but then there are severe complications which need immediate medical attention. Regularly visiting prenatal care allows doctors to detect signs of PUV early enough and ensure the PUV surgery on newborns is performed on time, thereby minimising the long-term damage. 

If you are looking for a specialist to address PUV in your newborn, Dr. Gursev, a renowned pediatric surgeon and urologist, offers expert care and treatment options tailored to your child’s needs. Book a consultation today to ensure your baby receives the best care possible.

B]  Causes and Risk Factors

The cause of PUV is not fully understood, but it is linked to developmental issues during urethra formation in male fetuses. Genetic factors play a role, as cases of PUV sometimes appear in siblings or identical twins, though it is not hereditary in most cases.

PUV is a condition unique to males because it involves the posterior urethra, a section of the urethra found only in boys. It affects approximately 1 in 8,000 male births. While maternal behaviours or environmental factors during pregnancy are not thought to cause PUV, early fetal ultrasounds are crucial for detecting signs of urinary system abnormalities.

Risk factors include:

• Male gender: PUV only occurs in boys.
• Family history: Rare cases of PUV have been reported in siblings, hinting at a potential genetic influence.

Understanding these factors can help families remain vigilant and seek early screening with expert doctors when necessary.

C]  Symptoms of Posterior Urethral Valves

Posterior urethral valve symptoms can range from mild to severe and may appear in infancy or later in childhood, depending on the degree of obstruction. Common symptoms include:

• Difficulty urinating: Infants with PUV may strain while urinating or have a weak or interrupted urine stream.
• Swollen abdomen: A visible distension of the belly due to an overfilled bladder or urine buildup.
• Frequent urinary tract infections (UTIs): Poor bladder emptying leads to residual urine, increasing the risk of infections.
• Failure to thrive: Infants may struggle with growth and weight gain due to chronic health issues caused by PUV.
• Feeding difficulties and vomiting: Often linked to kidney problems resulting from prolonged urine backup.

Additional signs may appear as children grow older, such as bedwetting (even after successful toilet training), increased urination frequency, or dribbling. In severe cases, dehydration and electrolyte imbalances may occur, requiring immediate medical attention.

D] Diagnosis of Posterior Urethral Valves

Early detection of PUV is essential to prevent complications like kidney damage. It is the most common cause of congenital urethral obstruction, and diagnosing PUV typically involves a combination of prenatal and postnatal tests:

1. Prenatal Ultrasound: A routine scan during pregnancy may reveal signs of PUV, such as an enlarged bladder or swollen kidneys (hydronephrosis). These findings often lead to closer monitoring.
2. Voiding Cystourethrogram (VCUG): This postnatal imaging test uses a contrast dye to map the urinary tract and identify blockages or urine reflux from the bladder into the kidneys.
3. Renal Ultrasound: After birth, this test assesses the condition of the bladder, ureters, and kidneys.
4. Blood Tests: Measuring kidney function markers like creatinine helps evaluate the extent of kidney damage caused by PUV.
5. Cystoscopy: In some cases, doctors use a small camera inserted into the urethra to visualise the valves and confirm the diagnosis directly.

The diagnosis process often involves a team of specialists, including pediatric urologists and nephrologists, who collaborate to create a comprehensive care plan.

E] Treatment Options

Posterior urethral valve treatment involves addressing the obstruction and managing complications, especially those related to kidney damage. The main approaches are:

1. Surgical Intervention:

• Valve Ablation: The most common and effective treatment for PUV, this minimally invasive procedure uses a cystoscope to remove or cut the obstructive membranes in the urethra.
• Vesicostomy: In cases where immediate relief is needed, posterior urethral valve surgery is done. The doctor creates a small opening in the bladder to drain urine directly.

2. Management of Kidney and Bladder Health:

• Antibiotics: Prescribed to prevent or treat urinary tract infections.
• Dialysis: In severe cases of kidney failure, temporary dialysis may be needed to remove waste and excess fluid from the body.

3. Long-Term Monitoring:

Lifelong follow-ups are essential for children treated for PUV. Regular tests help monitor kidney and bladder function early to catch any recurring issues.

• Supportive Care: Parents may receive guidance on hydration, infection prevention, and recognising symptoms of bladder or kidney problems.

With timely treatment, most children with PUV lead healthy lives, although some may face ongoing challenges such as incontinence or reduced kidney function.

When To Seek Medical Help?

Parents should consult a doctor immediately if their child shows symptoms like:

• Difficulty urinating or straining while peeing.
• A swollen or tight belly.
• Repeated urinary infections.
• Poor growth or signs of dehydration.

Prompt intervention can significantly reduce the risk of permanent kidney damage and improve the child’s overall health.