Isolated bladder exstrophy in prenatal diagnosis

Isolated classic bladder exstrophy (CBE) is the most common variant of the bladder-exstrophy-epispadias complex (BEEC). The BEEC represents a spectrum ranging from isolated epispadias over CBE to the most severe form, cloacal exstrophy. We report on a series of 12 cases with CBE diagnosed prenatally and illustrate the spectrum of prenatal ultrasound findings with comparison to prior published reports on this entity.

This was a retrospective study involving 12 fetuses with CBE at two large tertiary referral centers in Germany over a 14-year period (2004-2018).

Median diagnosis was made with ultrasound in 24 + 5 (IQR_25,75: 21 + 2, 29 + 0) weeks of gestation. All fetuses presented with the pathognomonic findings non-visualization of the fetal bladder and protruding abdominal mass below the umbilical cord insertion. All fetuses showed normal kidney anatomy and normal amniotic fluid throughout pregnancy. Epispadia was visible prenatally on ultrasound in 6/8 male fetuses. 1/12 Parents opted for termination of pregnancy, 11/12 fetuses were live born and received reconstructive surgery.

Isolated CBE is an extremely rare prenatal sonographic finding. Prenatal diagnostics should exclude additional malformations within the spectrum of cloacal malformations.