Introduction: Acute diverticulitis is inflammation due to micro-perforation of a diverticulum. Professional societies such as the American Society of Colon and Rectal Surgeons and the American College of Gastroenterology recommend that patients undergo colonoscopy to exclude colon cancer after an episode of acute diverticulitis. The aim of our study is to determine if there is an increased detection rate of malignancy and adenomas in colonoscopy performed after diverticulitis, if the patient had received a screening colonoscopy within five years prior of diverticulitis diagnosis.
Methods: IRB approved retrospective chart review from within the last 10 years spanning 12/2009 to 12/2020 at a single center study (Promedica Toledo Hospital) with appropriate ICD 10 codes were analyzed. A total of 946 patients were evaluated and out of these patients, 124 fit our inclusion criteria. Table 1 shows our patient selection process.
Results: 5.64% of patients were found to have Advanced Colonic Neoplasia (ACN). 0% were found to have Colorectal Cancer (CRC) on follow up. As a result, Advanced Adenoma (AA) was also found to be 5.64% in our single center study. Table 2 lists our follow up colonoscopy findings. Table 3 lists the clinical characteristics. For categorical data, Chi Square test was used to investigate differences in proportions, except where Fisher's Exact test was appropriate.
Discussion: Recent data for routine colonoscopy after acute uncomplicated diverticulitis showed a pooled prevalence of 5% for ACN, 1.5% for CRC, and 3.8% for AA. For patients at average risk for screening of colorectal cancer, a prevalence rate for CRC was found to be .20% and ACN was found to be 10.3%. Our study found 5.64% AA and 0% were found to have CRC on follow up. Patients who met our criteria did not have CRC detected upon follow up and had a lower detection rate of ACN compared to average risk population for normal screening of CRC. Though there was no detected CRC in our patient population, there was still notable detection of high risk polyps. This fact may be reason enough to continue colonoscopy after diverticulitis even in patients with screening colonoscopy within 5 years of their diverticulitis episode.
