Conservative management of anterior located anus: A medium-long term follow up

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

BACKGROUND

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.

METHODS

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.

RESULTS

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.

CONCLUSION

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.

Diagnosing Mild Forms of Anorectal Malformation With Anorectal Manometry: A Prospective Study

INTRODUCTION

Rectoperineal congenital anorectal malformations (CARMs) are diagnosed by examining the perineum, combined with electric stimulation (ES) of the anal sphincter performed under anesthesia. This procedure may be troublesome because it is based on the observed contractibility of the sphincter. We aimed to add 3-dimensional high-resolution anorectal manometry (3D-HRAM) to the procedure and to assess its value for diagnosing rectoperineal forms of CARM.

METHODS

We prospectively included 66 patients younger than 24 months who presented with constipation and were suspected of CARM, idiopathic constipation, or Hirschsprung disease. The patients were assessed between 2015 and 2021 at University Medical Center Groningen, the Netherlands. All patients underwent 3D-HRAM, followed by the standard diagnostic procedure for either CARM or Hirschsprung disease.

RESULTS

Of the 51 patients who underwent both 3D-HRAM and ES, we observed that patients with rectoperineal CARM revealed a pressure gap along the anterior part of the anal sphincter. Based on this observation, we diagnosed 35 patients with CARM. Subsequently, all 35 diagnoses were confirmed with ES. Sixteen patients were diagnosed as not having CARM, 100% of whom were in agreement with the gold standard-ES. Both the specificity and sensitivity of 3D-HRAM for diagnosing rectoperineal CARM were 100%.

DISCUSSION

We consider 3D-HRAM a reliable tool for diagnosing and excluding rectoperineal CARM. Using this method in patients suspected of CARM might keep infants from undergoing unnecessary interventions requiring anesthetics, such as ES. By providing objective insight into the functional capabilities of the anal sphincter, anorectal manometry adds to the diagnosis.

Comparison and impact of associated anomalies on the anal position index in neonates with anorectal malformation

OBJECTIVE

Some prognostic factors have affected the functional outcomes of patients with anorectal malformations (ARM) after definitive surgery, including the associated anomalies. Moreover, the anal position index (API) study in neonates from developing countries is minimal. We aimed to (1) compare the API between neonates with ARM and controls; and (2) determine the impact of associated anomalies on the API in neonates with ARM.

RESULTS

We ascertained 68 subjects: 35 neonates with ARM and 33 controls. The API of neonates with ARM was similar to controls, either male or female neonates (p = 0.51 and 0.90, respectively). Interestingly, the API in ARM males with associated anomalies (0.42 ± 0.07) was significantly lower than in control males (0.48 ± 0.02) (p = 0.005). Moreover, the API of ARM neonates with vertebral anomalies (0.35 ± 0.04) was lower than ARM neonates without vertebral anomalies (0.47 ± 0.07) (p = 0.021). In conclusion, associated anomalies and sex might affect the API in neonates with ARM. These findings should be considered and informed during counseling to the parents regarding the prognosis of functional outcomes in ARM neonates, particularly with associated anomalies.

Clinical Differentiation between a Normal Anus, Anterior Anus, Congenital Anal Stenosis, and Perineal Fistula: Definitions and Consequences—The ARM-Net Consortium Consensus

In the past, an anteriorly located anus was often misdiagnosed and treated as an anorectal malformation (ARM) with a perineal fistula (PF). The paper aims to define the criteria for a normal anus, an anterior anus (AA) as an anatomic variant, and milder types of ARM such as congenital anal stenosis (CAS) and PF. An extensive literature search was performed by a working group of the ARM-Net Consortium concerning the subject “Normal Anus, AA, and mild ARM”. A consensus on definitions, clinical characteristics, diagnostic management, and treatment modalities was established, and a diagnostic algorithm was proposed. The algorithm enables pediatricians, midwives, gynecologists, and surgeons to make a timely correct diagnosis of any abnormally looking anus and initiate further management if needed. Thus, the routine physical inspection of a newborn should include the inspection of the anus and define its position, relation to the external sphincter, and caliber. A correct diagnosis and use of the presented terminology will avoid misclassifications and allow the initiation of correct management. This will provide a reliable comparison of different therapeutic management and outcomes of these patient cohorts in the future.