Bladder exstrophy

Bladder exstrophy is a congenital abnormality that results in an “inside-out” bladder, where the bladder protrudes out of the abdomen, leaving the inside of the bladder exposed to the outside environment.

Normally, in the first trimester, endoderm in the hindgut expands to form the cloaca, which is a temporary structure that connects the urinary, digestive, and reproductive tracts.

Separately, the ectoderm forms the anterior abdominal wall. At around eight weeks of development three important things happen.

First, the anterior abdominal wall matures and forms the muscles and connective tissue of the lower abdomen. Second, the cloaca splits to form the urogenital sinus and rectum, the urogenital sinus later goes on to become the urinary and genital ducts, as well as the urinary bladder.

And third, the cloacal membrane opens up to the outside of the body, creating openings for the urogenital tract and anus.

All right, so bladder exstrophy occurs when the developing bladder and urethra herniate anteriorly and this causes some problems.

First, it prevents the normal development of the lower abdominal wall which leaves it open. Second, it prevents fusion of the pelvis leaving a wide split at the symphysis pubis.

Also, most cases of bladder exstrophy involve epispadias, which is where the urethra exits the top of the penis, but the opposite is not true, not all cases of epispadias involve bladder exstrophy.

One way to kind of think about the final result is to imagine the bladder and urethra, and making a cut through the top of the urethra and bladder, and also imagine that cut goes up through the symphysis pubis as well as the abdominal wall.

After that, imagine pushing on the bladder from the bottom until it’s inside out, and this is essentially is what the final defect in bladder exstrophy looks like, and that bladder pushes through the abdominal wall into the outside world.

In addition to this, bladder exstrophy causes other changes as well. For example, the anus is usually more anteriorly located.

Also, in boys the anterior part of the penis is shortened, and in girls, the vagina is wider and shorter and more vertically oriented.

The exact reason that bladder exstrophy happens in some infants is unknown, but one theory is that the mesenchymal cells fail to migrate between the endoderm of the cloaca and the ectoderm of the anterior abdominal wall.

Without mesenchymal support, the cloacal membrane becomes unstable and opens to the outside prematurely. And this creates a hole in the lower abdominal wall which exposes the internal structures to the outside.

Having an bladder and urethra exposed to the outside environment can lead to complications like incontinence as well as an increased risk of urinary tract infections.

As far as diagnosis, goes, the defect is clinically obvious when a baby is born, but is can also be diagnosed earlier on a prenatal ultrasound.

Generally, within the first few weeks of life, the bladder and urethral defect are surgically closed, but sometimes staged surgeries are needed over months or years.

All right, as a quick recap, bladder exstrophy is a congenital problem where the bladder protrudes through the front of the abdominal wall, and it’s often accompanied by epispadias.

It can cause incontinence and increase the risk of urinary tract infections, and requires early surgical correction. what's up guys Tanner here just want to give a special thanks to amanda for writing the script on that one as always you guys can help support us by donating on patreon as well subscribe to our Channel and tell your friends about us on social media