persistent cloaca

Last reviewed 01/2018

Persistent cloaca is the state of having the rectum, vagina and urinary tract meeting to fuse into a common channel of variable length. The perineum has a single orifice joined to the channel.

In over half of these patients the vagina is abnormal and full of mucus secretion - hydrocolops - causing distention. The expansion may be such that the trigone is compressed causing obstruction and subsequent mega-ureter.

There is a high incidence of urological abnormalities and as such, at the immediate fashioning of a protective colostomy, the urinary tract is assessed and, if necessary, diverted. The vagina is drained at the same time.

The definitive repair of a persistent cloaca - a posterior sagittal anorectovaginourethoplasty - is carried out at 6 months. The vagina is separated from the urinary tract - this may require a laparotomy if the common channel is longer than 3cm. The rectum is then separated from the vagina. Finally, the urethra is reconstructed using the old common channel, the vagina is sutured to the perineum, and the rectum is attached to the posterior sphincteric mechanism. Odd tissue arrangements may necessitate the use of bowel or skin flaps to refashion the area.

Prognosis is good for both gastrointestinal (80%) and urinary (70%) continence if the common channel is short.