Bladder exstrophy

Bladder exstrophy

Bladder exstrophy is a congenital disorder in which failure of development of the lower abdominal wall leads to an abdominal wall defect through which the bladder is exposed ( Figure 83.9 ). Diastasis of the pubic symphysis and an Hermann Johann Pfannenstiel , 1862–1909, gynaecologist, Breslau, Germany (now Wroc ł aw , Poland), described this ‘bikini-line’ suprapubic horizontal incision in 1900. anterior opening of the urethra (epispadias) can coexist. The - condition forms part of a spectrum of conditions ranging from epispadias to bladder exstrophy or to more severe cloacal exstroph y , the so-called exstrophy–epispadias complex. During - development, mesenchymal ingrowth between the ectodermal , and endodermal layers of the cloacal membrane leads to - formation of the lower abdominal wall muscles and pelvic bones. However, failure of this mesodermal ingrowth leads to premature rupture of the cloacal membrane and results in epispadias, bladder exstrophy or cloacal exstrophy depending on the developmental stage at which rupture occurs. The incidence of bladder exstrophy is approximately 1 in 46 /uni00A0 000 live births, with a male-to-female ratio of 2.3:1. Clinical features Exstrophy of the bladder can be associated with a spectrum of anomalies a ff ecting the external genitalia, urinary system, bony pelvis, abdominal wall, rectum and anus. Male external genitalia Shortened penis due to diastasis of the pubic symphysis resulting in wide separation of the crural attachments, and congenital deficiency of the corporeal tissue. Female external genitalia /uni25CF Shortened, stenotic and anteriorly displaced vagina. /uni25CF Bifid clitoris.

Figure 83.8 Bladder diverticulum following excision.

Urinary system /uni25CF Incompetent bladder neck continence mechanism. /uni25CF VUR due to lack of obliquity of the vesicoureteric junc tion. Bony pelvis /uni25CF Widening (diastasis) of the pubic bones due to malrotation of the innominate bones, leading to a waddling gait. /uni25CF External rotation of the anterior and posterior segments of the bony pelvis, leading to outward rotation of the lower limbs. /uni25CF /uni25CF /uni25CF /uni25CF /uni25CF /uni25CF /uni25CF /uni25CF /uni25CF /uni25CF /uni25CF /uni25CF /uni25CF James Parkinson , 1755–1824, general practitioner of Shoreditch, London, UK, published /uni25CF Low-set umbilicus with a triangular-shaped fascial defect of the lower abdominal wall. /uni25CF Higher incidence of indirect inguinal hernia owing to the lack of oblique muscle fibres of the inguinal canal and large internal and external inguinal rings. Anorectum /uni25CF Shortened perineum and anteriorly displaced anus. /uni25CF Imperforate anus (absence of the normal anal opening) or rectal stenosis. /uni25CF Rectal prolapse. Surgical treatment of bladder exstrophy The aim of surgical treatment is to preserve renal function, achieve urinary continence and create functional and cosmet - ically acceptable external genitalia. The modern staged repair of exstrophy consists of bilateral iliac osteotomies with bladder exstrophy and abdominal wall closure in the neonatal period, followed by epispadias repair and phallic reconstruction at 6 /uni00A0 months to 1 year of age, and finally bladder neck recon - struction and bilateral ureteric reimplantation (to treat VUR) at age 5–7 years. More recently , complete primary repair of exstrophy in the neonatal period has been advocated in an attempt to optimise outcomes with few er procedures and without a formal bladder neck closure procedure.

Figure 83.9 Bladder exstrophy. (Reproduced with permission from Wein AJ, Kavoussi LR, Partin AW, Peters CA. Campbell-Walsh urol ogy , 11th edn. Philadelphia, PA: Elsevier, 2016: 2424.) TABLE 83.3 Common congenital and acquired causes of neurogenic lower urinary tract dysfunction. Congenital Acquired Neural tube defects Sacral agenesis Anorectal malformations (e.g. VACTERL syndrome) Central nervous system tumours Transverse myelitis VACTERL, vertebral defects, anal atresia, cardiac defects, tracheo-oesophageal /f_i stula, renal anomalies and limb abnormalities.