Outcomes of Management of Anterior Anus in Girls in Glasgow, UK

Anterior anus is considered part of the spectrum of anorectal malformations in girls and has been associated with childhood constipation. However, limited literature exists on outcomes and associated malformations.

All girls <6 months referred to our centre with suspected anterior anus between January 2015 and December 2022 were identified. Data collected included patient demographics, presence of anomalies, operative management, laxative use and continence. Results are described using descriptive statistics and percentages.

147 girls were referred with suspected anterior anus of which 95 were confirmed to have an anterior anus. Median age of first assessment was 3 (0-13) months. Median follow up was 24 (1-94) months. 21 (22.1 %) had clinical concern of partial absence of normal circumferential anal corrugation. 10 (10.5%) girls underwent examination under anaesthesia; 4 patients underwent anoplasty with covering colostomy. Laxatives were prescribed in 31 (32.6%) girls. Of the 53 patients followed up to age 4 years and older, 51 (96.2%) achieved continence. On renal ultrasonography significant hydroureteronephrosis was detected in one patient. No significant spinal anomalies were detected on imaging. Two patients had ventricular-septal defects were identified. All significant anomalies were in patients with an ectopic anus/ perineal fistula.

This represents the largest reported series of girls with anterior anus. The incidence of identified associated malformations was low. Furthermore, laxative use and continence outcomes are similar to the general infant/childhood population. Screening and routine follow-up should be reserved for individual cases where there is clinical concern.