Inverted colonic diverticulum mimicking a polyp: A case report on diagnostic challenges and clinical implications

Inverted colonic diverticulum (ICD) is a rare intraluminal lesion that typically presents with a polypoid appearance, which can make it challenging to differentiate from colonic polyps. ICDs occur in about 0.7 % to 1.7 % of individuals, with a mean age of 59 years, and a slightly higher prevalence in males.

This case report presents a 40-year-old male with ICD that was misdiagnosed as polyp after a colonoscopy showed polypoid lesions in the context of diverticulosis and underwent polypectomy, colonoscopy completed. A few hours after the procedure, the patient developed symptoms consistent with complicated diverticulitis and required antibiotic treatment and CT-guided aspiration.

This case highlights the difficulty in differentiating ICD from colonic polyps during colonoscopy. Although ICDs are benign, they can closely resemble polyps, and misidentifying them may result in unnecessary and potentially harmful interventions. Endoscopists should be aware of the distinctive features of ICDs and employ techniques like probing and air insufflation to avoid unnecessary procedures.

Prompt recognition of ICDs can help prevent complications such as colonic perforation and unnecessary surgery, ultimately leading to improved patient outcomes.