1630 Rectal Duplication in a Middle-Aged Adult Presenting With Constipation and Abdominal Mass After Hysterectomy

Abstract

INTRODUCTION: Alimentary tract duplications are rare congenital malformation that usually presented since childhood. CASE DESCRIPTION/METHODS: A 43–year-old female presented with constipation and progressive enlargement of abdominal mass for 4 years. Her constipation symptoms started after she underwent hysterectomy for myoma uteri. She had straining and fecal soiling that was refractory to laxatives. Physical examination revealed a 25-cm non-tender hard mass at mid-lower abdomen. Digital rectal examination showed anal wink, normal sphincter tone, and empty rectum. Paradoxical anal sphincter contraction was presented while pushing. Other physical findings were unremarkable. CT abdomen showed marked dilatation of rectosigmoid colon with feces content with an abrupt change of caliber at upper rectum. Small bowel was not dilated. Barium enema study was shown in Figure 1. Colonoscopy showed a 1.5-cm opening of a large blind pouch at 10 cm above anal verge. Anorectal manometry revealed dyssynergic defecation type II with rectal hyposensitivity with delayed balloon expulsion time. The patient underwent a complete transabdominal resection of the duplication with temporary loop sigmoid colostomy. Gross findings showed a large uniloculated cyst (Figure 2). Pathological findings showed a cystic lesion lined by complete colonic wall (Figure 3). DISCUSSION: Rectal duplications are rare congenital anomalies (1/200,000 live births) and seventy percent of them are diagnosed before the age of two. They can be classified as type I (cystic) and type II (tubular) with or without communication to rectum or perineum. The wall of the duplications is typically lined with complete rectal wall. Surgical removal is indicated as it prevents septic and carcinogenic complications [1]. Our patient’s symptoms interestingly occurred late in adulthood after surgery. Removal of uterus and myoma uteri might change the angle of the duplication’s opening. Also, the presence of dyssynergic defecation might contribute and cause gradual accumulation of fecal content inside. Three months post-operative anorectal manometry still showed dyssynergia but improved rectal sensitivity. At present, our patient has bowel movement every 1-2 days per colostomy with minimal usage of laxative and is currently undergoing biofeedback training before colostomy closure.