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The prevalence at birth for the whole spectrum is reported at 1/10,000, ranging from 1/30,000 for CEB to 1/200,000 for EC, with an overall greater proportion of affected males.

EEC is characterized by a visible defect of the lower abdominal wall, either with an evaginated bladder plate (CEB), or with an open urethral plate in males or a cleft in females (E). Urine drips from the ureteric orifices, visible on the bladder surface or per urethram. In the rare cases of CE, two exstrophied hemibladders, as well as omphalocele, an imperforate anus and spinal defects, can be seen after birth. Atypical forms of the EEC (duplicated exstrophy, covered exstrophy and pseudo-exstrophy) have also been described. EEC results from mechanical disruption or enlargement of the cloacal membrane, which prevents the invasion of mesodermal cells along the infraumbilical midline and thereby results in exstrophy. The timing of the rupture determines the severity of the malformation.

The underlying cause remains unknown: rare cases of familial occurrence have been reported and both genetic and environmental factors are likely to play a role in the etiology of EEC.

Diagnosis at birth is made on the basis of the clinical presentation but EEC may be detected prenatally during careful ultrasound examinations with the index finding of repeated non-visualization of a normally filled fetal bladder.

Extensive counseling should be provided to parents but due to a generally favorable outcome with appropriate surgical management, termination of the pregnancy should no longer be systematically recommended.

Management is primarily surgical, with the main aims of obtaining secure abdominal wall closure, achieving urinary continence with preservation of renal function, and, finally, adequate cosmetic and functional genital reconstruction. Currently, several methods for bladder reconstruction with creation of an outlet resistance (either as a staged or a one-stage approach) during the newborn period are favored worldwide. Removal of the bladder template with complete urinary diversion to a rectal reservoir can be an alternative. After reconstructive surgery of the bladder, continence rates of about 80% are expected during childhood. Though spontaneous voiding is the main issue, additional surgery might be needed to optimize bladder storage and emptying function. In cases of definite reconstruction failure, urinary diversion should be undertaken. In puberty, genital and reproductive functions constitute increasingly important issues for both sexes. Psychosocial and psychosexual outcome reflect the importance of long-term care (from birth into adulthood) from a multidisciplinary team of experts for parents and children with EEC to facilitate an adequate quality of life.