Prune Belly Syndrome
2 day old male
Publication Date: 2010-02-10
2 day old male admitted for suspicion of obstructive nephropathy
Plain film: Bulging abdominal flanks, with bowel loops extending laterally. Slightly splayed lower ribs.
Prune Belly Syndrome
Prune belly Syndrome is a rare congenital anomaly affecting 1 in 40,000 births, mainly males [1, 2]. Other names for the syndrome include abdominal muscle deficiency Syndrome, congenital absence of the abdominal muscles, Eagle-Barrett Syndrome , Obrinsky Syndrome , Fröhlich Syndrome, or rarely, Triad Syndrome.
The typical infant with the prune belly syndrome has a wrinkled prune-like appearance of the abdominal wall due to partial or complete lack of abdominal muscles and undescended testes. The posterior urethra is elongated and dilated, has a funnel-shaped appearance that resembles a posterior urethral valve; however, the presence of a valve is unusual in prune belly syndrome. The bladder in prune belly syndrome has markedly enlarged capacity, is vertical in orientation, and is often thick-walled. In some patients, a bulging conical dome of the bladder represents persistent urachus. The bladder usually is distended at the trigonal region and vesicoureteral reflux often occurs. A large post void residual volume is also a frequent occurrence.
It has been suggested that the urogenital anomalies in Prune Belly Syndrome can be attributed to a functional urethral obstruction which is the result of prostatic hypoplasia . It was postulated that a “kink” in a short segment of the prostatic urethra, just above the membranous urethra, leads to the obstructive changes of the bladder including hypertrophy, dilatation, hydroureter, hydronephrosis, and renal dysplasia, which are seen higher in the urinary tract . In a different study , it was suggested that in prune belly syndrome, prostatic growth and development are hindered because of destruction or absence of the appropriate primitive mesenchyme. This may contribute to the dilatation of the posterior urethra and mimics the appearance of posterior urethral valve in voiding cystourethrography.
- Baird PA, MacDonald EC (1981) An epidemiologic study of congenital malformations of the anterior abdominal wall in more than half a million consecutive live births. Am. J. Hum. Genet. 33(3): 470–8
- Eagle JF, Barrett GS (1950) Congenital deficiency of abdominal musculature with associated genitourinary abnormalities: A syndrome. Report of 9 cases. Pediatrics 6(5): 721–36.
- Obrinsky W (1949) Agenesis of abdominal muscles with associated malformation of the genitourinary tract; a clinical syndrome. Am J Dis Child 77(3): 362–73
- Frolich, F. Der Mangel der Muskeln, insbesondere der Seitenbauchmuskeln (1989) Dissertation: Wurzburg
- Moerman P, Fryns JP, Goddeeris P, Lauweryns JM (1984) Pathogenesis of the prune-belly syndrome: a functional urethral obstruction caused by prostatic hypoplasia. Pediatrics 73(4): 470-5
- Hoagland MH, Hutchins GM (1987) Obstructive lesions of the lower urinary tract in prune belly syndrome. Archives of pathology & laboratory medicine 111(2): 154-6
- Popek EJ, Tyson RW, Miller GJ, Caldwell SA (1991) Prostate Development in Prune Belly Syndrome (PBS) and Posterior Urethral Valves (PUV): Etiology of PBS-Lower Urinary Tract Obstruction or Primary Mesenchymal Defect? Fetal & Pediatric Pathology 11(1): 1-29