A single-center retrospective study of the surgery outcome of Megarectosigmoid (MRS) after anorectal malformation (ARM) repair

Background: The Megarectosigmoid (MRS) after anorectal malformation (ARM) repair can have a negative impact on the pediatric quality of life. However, current treatments lack consensus due to variable efficacy. Objective: To evaluate the long-term outcome of laparoscopic-assisted MRS resection (resection of the dilated sigmoid colon and rectum) with anal reconstruction (LAMR-AR) and provide the indications to surgical treatment for MRS. Methods: A retrospective cohort analyzed 49 pediatric MRS patients, who all had underwent ARM repair before LAMR-AR. Clinical data included imaging and surgical parameters. Patients were stratified by anal morphology: normal anus group (NAG) vs abnormal anus group (AAG) (stenosis/ectopic anus). Functional outcomes were assessed via Rintala scores (R-score) and Krickenbeck criteria for soiling/constipation. Results: This study enrolled a cohort of 49 pediatric patients (28 males, 21 females) with a median age of 2.75 years (interquartile range [IQR]: 1.42–3 years). Postoperatively, in normal anus group, constipation decreased from 92.9%(26/28 grade3:26) to 7.1%(2/28 grade2:1 grade3:1)(p<0.01), while soiling increased from 3.6%(1/28 grade3:1) to 57.1%(16/28 grade1:9 grade2:7)(p<0.01). As for the abnormal anus group, constipation decreased from 85.7%(18/21 grade3:18) to 23.8%(5/21 grade2:4 grade3:1)(p<0.01) and soiling increased from 4.8%(1/21 grade3:1) to 71.4%(15/21 grade1:2 grade2:9 grade3:4)(p<0.01).Cases in abnormal anus group showed higher complications after ARM repair rates (32.1% vs 14.3%, p = 0.04 abnormal anus group: wound infection/abscess (5), mucosal prolapse (6), recurrent urethral fistula (1), vaginal fistula (1), vestibular fistula (1), wound dehiscence (1) vs normal anus group: cutaneous fistula (1), urethral fistula (1), perianal abscess (1), mucosal prolapse (1)) and worse outcome in lower R-scores(NAG:17(15–19);AAG:14(11–16) p = 0.012). Conclusion: LAMR-AR is more recommended for patients without anal abnormalities.