Phimosis as a cause of the prune belly syndrome: comparison to a more common pattern of proximal penile urethra obstruction.

The pathogenesis of the prune belly syndrome (PBS) remains controversial, but two theories predominate. The first theory supports an obstructive phenomenon early in gestation leading to irreversible damage to the genitourinary tract and abdominal wall. The second theory suggests mesodermal injury between the 6th and 10th weeks of gestation as the primary abnormality. This paper reports of two fetuses with the PBS phenotype that were examined postmortem at our institution. Thorough examination of the lower urinary tract allowed demonstration of anatomic obstruction of the urethra in both cases. One case illustrated a relatively common pattern of proximal penile urethral obstruction, a flap-like obstruction between the prostatic and penile urethra. The other case provided what we believe to be the first description of PBS caused by severe phimosis.