Anoplasty for low anorectal malformation.

Background: The presence of a slightly anterior, stenotic anus is a low anorectal malformation. It is a type of rectoperineal fistula. The cardinal symptoms are constipation and straining at stool. Hendren described a technically simple anoplasty for this condition in 1978. Controversy about terminology has led to a lack of clarity about this condition.

Methods: Clinical data were reviewed about the authors' patients, who had Hendren anoplasty, from 2009 to 2015. Followup data were obtained from office visits and telephone interviews with families and primary care doctors.

Results: Seven patients (4 boys) presented with intractable constipation. All had a stenotic anal orifice, located anterior to the center of the anal wink, within the pigmented perianal skin. In 4 of 7 cases, the lesion was not recognized at birth. Anoplasty was performed at a median age of 8months (range 6-28). Late followup information was obtained on six of the seven patients at a median of 32months (range 28-61). Four reported no or minimal laxative requirement and two reported daily laxative use but good symptom control.

Conclusions: Low anorectal malformation/rectoperineal fistula may be overlooked in the newborn. When symptomatic, it may be corrected by a simple anoplasty with excellent results.