|Classification and external resources|
Bladder exstrophy (also known as Ectopia vesicae) is a congenital anomaly that exists along the spectrum of the exstrophy-epispadias complex and most notably involves protrusion of the urinary bladder through a defect in the abdominal wall. Its presentation is variable, often including abnormalities of the bony pelvis, pelvic floor, and genitalia. The underlying embryologic mechanism leading to bladder exstrophy is unknown, though it is thought to be in part due to failed reinforcement of the cloacal membrane by underlying mesoderm.
Occuring at a rate between 1 in 10,000 to 1 in 50,000  with a male-to-female ratio of 2.3-6:1, bladder exstrophy is relatively rare. Though, for those individuals with bladder exstrophy who maintain their ability to reproduce the risk of bladder exstrophy is approximately 500-fold greater than the general population.
The classic manifestation of bladder exstrophy presents with:
- A defect in the abdominal wall occupied by both the exstrophied bladder as well as a portion of the urethra
- A flattened puborectal sling
- Separation of the pubic symphysis
- Shortening of the pubic ramii
- External rotation of the pelvis.
Males lack anterior corporal tissue, which coupled with the separation of the pubic symphysis results in a penis that is both actually shortened and also appears shorter than it is. In addition, they may experience chordee and epispadias.
In a small retrospective study of 25 pregnancies five factors were found to be strongly associated with a prenatal diagnosis of bladder exstrophy:
- The bladder was not visualized on ultrasound in 71% of cases
- A lower abdominal bulge representing the exstrophied bladder was seen in 47% of cases
- A small penis with anteriorly displaced scrotum was identified in 57% of males
- The umbilical insertion was low set in 29% of cases
- Abnormal widening of the iliac crests was seen in 18% of cases
While a diagnosis of bladder exstrophy was made retrospectively in a majority of pregnancies, in only three cases was a prenatal diagnosis made.
Management at Birth
Upon delivery, the exposed bladder is irrigated and a non-adherent film is placed to prevent as much contact with the external environment as possible. In the event the child was not born at a medical center with an appropriate exstrophy support team then transfer will likely follow. Upon transfer, or for those infants born at a medical center able to care for bladder exstrophy, imaging may take place in the first few hours of life prior to the child undergoing surgery.
It is imperative that the bladder be adequately assessed by a surgeon with significant experience in exstrophy repair, as the decision of whether to wait or close immediately has implications for the long-term well-being of the child. Primary (immediate) closure is indicated only in those patients with a bladder of appropriate size, elasticity, and contractility as those patients are most likely to develop a bladder of adequate capacity after early surgical intervention.
Conditions that are absolute contraindications despite bladder adequacy include duplication of the penis or scrotum and significant bilateral hydronephrosis.
Modern therapy is aimed at surgical reconstruction of the bladder and genitalia, most often through a staged approach. The initial surgical management consists of bladder, posterior urethral and abdominal wall closure (with or without osteotomies). Bladder closure may be delayed if the bladder is deemed too small to close. The surgical management epispadius usually occurs at approximately 6–12 months of age. Reconstruction of the bladder neck is typically done at toilet training age (approximately age 4-5), once the child is able to and interested in participating in a bladder retraining program. In very carefully selected patients surgical management may be carried out in a single stage or in combined procedures.
Even with successful surgery, patients may have long-term problems with
- urinary reflux (see Vesicoureteral reflux)
- repeated urinary tract infections
- bladder adenocarcinoma
- colonic adenocarcinoma
- uterine prolapse
Sexual function and libido are normal in exstrophy patients. Successful pregnancies and delivery in exstrophy patients have been reported.
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- Gearhart JP, Jeffs RD: The bladder exstrophy-epispadias complex. In: Walsh PC, et al ed. Campbell's urology, 7th ed. Philadelphia: WB Saunders; 1998:1939.
- Gargollo PC, Borer JG (2007). "Contemporary outcomes in bladder exstrophy". Current Opinion in Urology 17 (4): 272–80. doi:10.1097/MOU.0b013e3281ddb32f. PMID 17558272.
- Exstrophy of the Bladder - The Children's Hospita of Philadelphia
- Bladder exstrophy page at Children's Hospital Boston
- http://www.bladderexstrophy.com/patient_support.htm#Canada. Bladder exstrophy support groups by region