title: Colonoscopy after CT-diagnosed acute diverticulitis: Is it really necessary?
abstract: BACKGROUND
  Computed tomography (CT) scans are commonly used to diagnose acute diverticulitis, but there are overlapping features between diverticulitis and colorectal cancer (CRC) on imaging studies. Hence, colonoscopy is typically recommended after an episode of acute diverticulitis to rule out underlying malignancy. Currently, 64-slice multidetector CT scanners are capable of providing higher-resolution images and may be able to distinguish malignancy from diverticular inflammation. We aimed to determine the prevalence of CRC among patients with CT-diagnosed acute diverticulitis.
  
  
  METHODS
  We performed a retrospective study of patients with acute diverticulitis diagnosed on CT scan between December 2005 and December 2010 at St. Paul's Hospital, Vancouver, BC. Nonresidents were excluded. We reviewed CT scan reports that included the term "diverticulitis," reports of follow-up colonic evaluation within 1 year of diagnosis and pathology results. We queried the provincial cancer registry to ensure no cases of CRC were missed.
  
  
  RESULTS
  A total of 293 patients had acute diverticulitis diagnosed on CT scan, but 8 were nonresidents and were excluded. Of the 285 included in the analysis, the mean age was 59.4 ± 15.1 years, and 167 (58.6%) were men. Among the 114 patients who underwent follow-up evaluation, malignancy was diagnosed in 4 (3.5%). The overall prevalence of malignancy among patients with CT-diagnosed diverticulitis was 1.4%.
  
  
  CONCLUSIONS
  Routine endoscopic evaluation after an episode of diverticulitis diagnosed with high-resolution CT scan does not appear to be necessary. Selective approach in patients with protracted clinical course or those with mass lesion/obstruction on CT scan may be of benefit.
authors.affiliation: From the Department of Medicine, Division of Gastroenterology (Ou, Rosenfield, Bressler) and the Department of Radiology (Brown), St. Paul's Hospital, University of British Columbia, Vancouver, BC; the Department of Medicine, Vancouver General Hospital, University of British Columbia, Vancouver, BC (Chan); the Department of Family Medicine, University of Calgary, Calgary, Alta (Hong); and the Department of Medical Oncology, British Columbia Cancer Agency, University of British Columbia, Vancouver, BC (Lim).
authors.forename: George
authors.initials: G
authors.lastname: Ou
authors.affiliation: From the Department of Medicine, Division of Gastroenterology (Ou, Rosenfield, Bressler) and the Department of Radiology (Brown), St. Paul's Hospital, University of British Columbia, Vancouver, BC; the Department of Medicine, Vancouver General Hospital, University of British Columbia, Vancouver, BC (Chan); the Department of Family Medicine, University of Calgary, Calgary, Alta (Hong); and the Department of Medical Oncology, British Columbia Cancer Agency, University of British Columbia, Vancouver, BC (Lim).
authors.forename: Greg
authors.initials: G
authors.lastname: Rosenfeld
authors.affiliation: From the Department of Medicine, Division of Gastroenterology (Ou, Rosenfield, Bressler) and the Department of Radiology (Brown), St. Paul's Hospital, University of British Columbia, Vancouver, BC; the Department of Medicine, Vancouver General Hospital, University of British Columbia, Vancouver, BC (Chan); the Department of Family Medicine, University of Calgary, Calgary, Alta (Hong); and the Department of Medical Oncology, British Columbia Cancer Agency, University of British Columbia, Vancouver, BC (Lim).
authors.forename: Jacqueline
authors.initials: J
authors.lastname: Brown
authors.affiliation: From the Department of Medicine, Division of Gastroenterology (Ou, Rosenfield, Bressler) and the Department of Radiology (Brown), St. Paul's Hospital, University of British Columbia, Vancouver, BC; the Department of Medicine, Vancouver General Hospital, University of British Columbia, Vancouver, BC (Chan); the Department of Family Medicine, University of Calgary, Calgary, Alta (Hong); and the Department of Medical Oncology, British Columbia Cancer Agency, University of British Columbia, Vancouver, BC (Lim).
authors.forename: Nathan
authors.initials: N
authors.lastname: Chan
authors.affiliation: From the Department of Medicine, Division of Gastroenterology (Ou, Rosenfield, Bressler) and the Department of Radiology (Brown), St. Paul's Hospital, University of British Columbia, Vancouver, BC; the Department of Medicine, Vancouver General Hospital, University of British Columbia, Vancouver, BC (Chan); the Department of Family Medicine, University of Calgary, Calgary, Alta (Hong); and the Department of Medical Oncology, British Columbia Cancer Agency, University of British Columbia, Vancouver, BC (Lim).
authors.forename: Thomas
authors.initials: T
authors.lastname: Hong
authors.affiliation: From the Department of Medicine, Division of Gastroenterology (Ou, Rosenfield, Bressler) and the Department of Radiology (Brown), St. Paul's Hospital, University of British Columbia, Vancouver, BC; the Department of Medicine, Vancouver General Hospital, University of British Columbia, Vancouver, BC (Chan); the Department of Family Medicine, University of Calgary, Calgary, Alta (Hong); and the Department of Medical Oncology, British Columbia Cancer Agency, University of British Columbia, Vancouver, BC (Lim).
authors.forename: Howard
authors.initials: H
authors.lastname: Lim
authors.affiliation: From the Department of Medicine, Division of Gastroenterology (Ou, Rosenfield, Bressler) and the Department of Radiology (Brown), St. Paul's Hospital, University of British Columbia, Vancouver, BC; the Department of Medicine, Vancouver General Hospital, University of British Columbia, Vancouver, BC (Chan); the Department of Family Medicine, University of Calgary, Calgary, Alta (Hong); and the Department of Medical Oncology, British Columbia Cancer Agency, University of British Columbia, Vancouver, BC (Lim).
authors.forename: Brian
authors.initials: B
authors.lastname: Bressler
mesh_terms: D000328:Adult; D000368:Aged; D001955:British Columbia / Q000453:epidemiology; D003113:Colonoscopy; D015179:Colorectal Neoplasms / Q000175:diagnosis* / Q000453:epidemiology; D004239:Diverticulitis, Colonic / Q000000981:diagnostic imaging* / Q000453:epidemiology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D012042:Registries / Q000706:statistics & numerical data*; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed