What is bladder exstrophy?
Bladder exstrophy is an abnormality present at birth in which the bladder and associated structures aren’t correctly formed. Rather than being its normal round shape, the bladder is flattened, and the inside of the bladder is exposed outside the abdomen.
There are associated deficiencies of the abdominal muscles and pelvic bones also.
How often does bladder exstrophy occur?
Bladder exstrophy is rare. The amount varies all over the world, but roughly one out of every 30,000 babies are born with it. It’s slightly more common in males than females.
The risk of a family having more than one child with this condition is approximately one in 100. If one of the parents has the condition, there’s a risk of one in 70 that your child will have it too.
Recent published evidence suggests that the risk of bladder exstrophy in children born as a result of assisted fertility techniques is seven times greater than in children conceived naturally without assistance.
Why does it happen?
No one knows for sure, but there are a few theories. One thing we can assure you of,: i It’s not caused by anything the parents did or didn’t do during pregnancy.
Some experts believe that during the 11th week of pregnancy, the embryo undergoes structural changes including ingrowth of tissue in the lower abdominal wall, which stimulates development of muscles and pelvic bones. Up to this point, the primitive bladder and rectum are contained within tissue called the cloacal membrane.
The rectum then separates from the bladder, and if migration of tissue towards the midline over the primitive bladder fails the cloacal membrane may rupture, creating an exstrophied bladder.
Bladder exstrophy is usually an isolated birth defect. However, spinal cord abnormalities occur in about 13 percent of cases.
How is bladder exstrophy diagnosed?
We can often detect this condition before your baby is born, by using a routine sonogram. If doctors don’t see it then, the condition will be obvious at birth.
What will happen when the child is born?
If a bladder exstrophy condition has been detected beforehand, arrangements will be made for birth at a specialist unit, where a pediatrician and surgeon can assess the baby immediately.
If the condition isn’t found until your baby’s birth, transfer to such a unit for assessment will need to be arranged for the first day of life.
In either case, the bladder will be visible on the outside of the baby's abdomen. From there, we can assess the baby’s bladder size and quality, the shape of the pelvis and the condition of the genitals.
What treatments are available?
We treat bladder exstrophy through surgery. There are several options available, depending on how severe your child’s condition is.
The primary treatment objectives are:
Securely closing the bladder and pelvis
Restoring geniatalia in both boys and girls so that it looks and functions normally
Achieving urinary continence while ensuring preservation of kidney function
Modern staged reconstruction
This procedure involves three key steps:
Closure of the bladder and pelvis when your baby is a newborn.
Early reconstruction of the epispadiac urethra at approximately six to 12 months of age.
Bladder neck surgery to achieve continence when the bladder is big enough and your child is psychologically ready to be dry (often around four to five years of age).
From there, further operations may be needed to improve continence. Also, surgery to improve the external genitalia is almost always required.
In select cases where the bladder is of good quality and the penis is of good size, closure of the bladder and reconstruction of the penis and urethra can be combined in one operation. This is very technically demanding surgery and should only be performed by a experienced exstrophy surgeon.
The results of staged reconstruction are well documented. Given the development of a bladder with sufficient capacity, continence can be achieved in up to 90 percent of cases.
The most important factors in achieving continence are the quality of the bladder template and a successful initial bladder closure in the newborn.
Sometimes a baby is born with a bladder of especially poor quality, meaning it can’t be closed in the way described above. In these cases, different management is adopted.
Using techniques of modern reconstructive surgery, it is exceptionally rare for a child to reach late adolescence without achieving bladder control and external genitalia that look and function normally.
Other methods of treatment involve urinary diversion where the normal flow of urine is re-routed.