P1231 - Segmental Colitis-Associated Diverticulosis Mimicking an Obstructive Recto-Sigmoid Mass Complicated by Bowel Perforation

Marcel R. Robles, MD¹, Mohammad Abudalou, MBBS², Christopher G. Stallwood, MD³, Michael Russell, MD^4
1Tufts University School of Medicine, St. Elizabeth's Medical Center, Boston, MA; ²St. Elizabeth's Medical Center, Tufts University School of Medicine, Brighton, MA; ³Tufts University, St. Elizabeth's Medical Center, Brighton, MA; ⁴Tufts University Medical Center, Boston, MA

Introduction: Segmental colitis associated with diverticulosis (SCAD) is a rare form of diverticular disease defined by a self-limited inflammation at the level of a colonic area surrounding a diverticulum, without involvement of the diverticulum. It is commonly found in the sigmoid colon, typically in males over the age of 50. It is often misdiagnosed as inflammatory bowel disease or occult malignancy.

Case Description/Methods: A 44 year old male with a history of left nephrectomy and stage III chronic kidney disease presented to our institution with a four day history of constipation and rectal pressure. He endorsed bloating with increased straining during bowel movements, resulting in minimal amounts of stool. No history of chronic constipation, weight loss, fever, abdominal pain or rectal bleeding was reported. Physical exam and laboratory studies were unremarkable. Computed tomography (CT) of the abdomen and pelvis without contrast reported a recto-sigmoid colon mass without signs of obstruction which was noted to have adjacent lymphadenopathy measuring up to 4 x 3.5 cm, concerning for metastatic disease (Figure 1a). Subsequent CT with contrast for clinical staging evidenced a partially obstructing recto-sigmoid mass with evidence of tumor perforation described as fluid in the perirectal space. (Figure 1b). The patient was started on antibiotic therapy due to concern for perforation. He remained hemodynamically stable with a normal abdominal exam. A high risk flexible sigmoidoscopy was performed. On sigmoidoscopy, congested and erythematous mucosa in the recto-sigmoid junction was noted around a single diverticulum with no sign of inflammation. (Figure 1c and 1d). The surrounding mucosa was biopsied and pathology revealed a colonic mucosa with iron deposits within the lamina propia consistent with findings suggestive of SCAD.

Discussion: SCAD is characterized by hematochezia and cramping abdominal pain. Diagnosis is made based on endoscopic and histopathology findings. Perforation as a complication of SCAD is unusual and more commonly seen with severe diverticulitis. Initial presentation and imaging in this case triggered a workup for colorectal malignancy, however, subsequent endoscopy was negative for a mass lesion and instead pathology revealed SCAD. Although rare, this case serves to illustrate a plausible diagnosis for future cases with similar presentations and provides support for minimally invasive approaches to diagnosis in the setting of possible perforation with signs of clinical stability.



Disclosures:


Marcel R. Robles, MD¹, Mohammad Abudalou, MBBS², Christopher G. Stallwood, MD³, Michael Russell, MD⁴. P1231 - Segmental Colitis-Associated Diverticulosis Mimicking an Obstructive Recto-Sigmoid Mass Complicated by Bowel Perforation, ACG 2021 Annual Scientific Meeting Abstracts. Las Vegas, Nevada: American College of Gastroenterology.