Bladder exstrophy

Bladder exstrophy is part of a spectrum of genito-urinary tract anomalies ranging from epispadias to cloacal exstrophy. It involves defects in the abdominal wall, bladder, genitalia, pelvic bones, rectum, and anus. There is a triangular fascial defect which is occupied by the exstrophied bladder and posterior urethra. This defect extends from the umbilicus, which is situated below the horizontal line of the iliac crest, to the intrasymphyseal band. Indirect inguinal hernias are frequently present. It is characterized by the absence of a portion of the lower abdominal wall and the anterior vesical wall, with eversion of the posterior vesical wall through the deficit. The bladder mucosa may be normal at birth or there may be hamartomatous polyps, or more rarely ectopic bowel mucosa, or an isolated bowel loop on the surface. The ureters follow an abnormal course due to the enlarged and deep pouch of Douglas. This forces the ureters to be inferiorly and laterally displaced. With bladder closure vesico-ureteral refl ux occurs in 100% of cases. Patients with classic bladder exstrophy have widening of the pubic symphysis, external rotation of the posterior aspect of the pelvis, retroversion of the acetabulum, external rotation of the anterior pelvis, and a 30% shortening of the pubic bones. The incidence of bladder exstrophy is estimated to be between 1 in 10,000 and 1 in 50,000 live births. There is a male preponderance with a male to female ratio of 5:1 to 6:1.