Bladder exstrophy: a bladder that is open at birth

What is bladder exstrophy?

In the womb, the lower part of the belly wall and the front wall of the bladder do not fully form. As a result, the baby is born with the bladder open: a red, moist surface is visible on the lower belly. Urine constantly flows out from the openings of the ureters on this surface.

Exstrophy is not limited to the bladder. These children usually also have:

• pubic bones that are spread apart (the pelvis does not form a closed ring),
• in boys, a short penis that curves upward, with the urethra open on the top side (epispadias),
• in girls, a clitoris split into two halves, with the vaginal opening placed further forward,
• a belly button that sits lower than usual and an anus moved slightly forward,
• an inguinal hernia, which is common.

The exstrophy-epispadias complex

Bladder exstrophy is part of a spectrum called the exstrophy-epispadias complex:

• Epispadias: the mildest form; only the urethra is open on the top side.
• Classic bladder exstrophy: the bladder and urethra are open.
• Cloacal exstrophy: the most severe form; the bowel is also involved.

How common is it?

Classic bladder exstrophy is rare: about one in 30,000–50,000 births, more often in boys than in girls. Cloacal exstrophy is even rarer.

How is it found?

During pregnancy

Exstrophy is often suspected on prenatal ultrasound. Typical signs:

• the bladder is not seen on repeated scans, even though the amount of amniotic fluid is normal,
• the umbilical cord attaches to the belly lower than usual,
• a bulge on the lower belly,
• small or unusual-looking genitals.

A fetal MRI is done when needed. If exstrophy is suspected, the family is advised to meet a pediatric urologist in advance and to plan the birth at a center experienced in exstrophy care, or with a way to transfer the baby there quickly.

After birth

The diagnosis is made at birth from the appearance. In the first hours, these steps matter:

• the umbilical cord is tied with a suture, not a plastic clamp, because a clamp can damage the bladder surface,
• the bladder is covered with clear plastic wrap, not gauze or a dressing, and rinsed with saline at each change,
• the baby is referred to an experienced center in the first days.

Tests

• Ultrasound: the kidneys and ureters. In classic exstrophy the kidneys are usually normal at birth.
• X-ray or other imaging to assess the pelvic bones.
• In cloacal exstrophy, ultrasound or MRI of the spine and spinal cord.
• At later stages, assessment of bladder size and function, and urodynamics when needed.

Treatment

Treatment is surgical and should be done only by a multidisciplinary team that is experienced in exstrophy and treats these patients regularly. The success of the first operation is one of the factors that most affects later results.

The goals of treatment:

• to close the bladder and belly wall securely,
• to protect the kidneys,
• to achieve urinary control,
• to give the genitals an acceptable appearance and preserve their function.

Teams use two main approaches:

• Staged repair: the bladder is closed in the newborn period or a few months later; in boys, the epispadias repair is done later, in infancy or early childhood. Reconstruction of the bladder neck is done when the bladder has grown large enough and the child is old enough to take part in the treatment.
• Complete primary repair: bladder closure and epispadias repair are done in a single operation.

The choice depends on the child’s condition and the team’s experience. To bring the pubic bones together and make the closure more secure, an operation on the pelvic bones (osteotomy) is often done. After surgery, the child is kept still for a period of time.

Achieving urinary control sometimes takes several operations. If the bladder stays small, enlarging it with a piece of bowel and emptying it with a catheter may be discussed. To make catheterization easier, a small channel can be created from the belly button to the bladder (Mitrofanoff). More about intermittent catheterization: neurogenic bladder.

After bladder closure, most children have vesicoureteral reflux, so with any fever the urine must be checked for infection.

Cloacal exstrophy

Cloacal exstrophy is the most severe form of the exstrophy-epispadias complex. The bladder is open and split into two halves, with a bowel surface visible between them. There is often no anal opening, and anomalies of the spine and spinal cord, and sometimes of the kidneys and legs. Some babies are born prematurely.

Treatment is done in many stages by a large team: neonatologist, pediatric surgeon, pediatric urologist, neurosurgeon, orthopedic surgeon, endocrinologist and psychologist. Decisions about genital reconstruction can be complex and are made together with the family.

Long-term outlook and follow-up

Children with exstrophy are followed for life. Follow-up includes:

• checking the kidneys with ultrasound and watching for urinary tract infections,
• urinary control and bladder emptying,
• conversations about sexual function and fertility in adolescence,
• in women, watching for later weakness of the pelvic floor and prolapse of the uterus,
• check-ups in adulthood because of a slightly increased risk of bladder cancer, especially if the bladder was enlarged with bowel,
• emotional support for the child and family.

In adolescence, the young person should be handed over in a planned way to an adult urologist familiar with exstrophy. This transition matters so that there is no gap in follow-up.

When to see a doctor

• If the bladder is not seen on a pregnancy ultrasound or exstrophy is suspected, meet a pediatric urologist before the birth.
• A baby born with exstrophy should be seen at an experienced center in the first days.
• If a child who has had surgery has a fever, passes less urine, has a wound that opens or has a catheter problem, seek care urgently.