Colonic diverticulitis: a prospective analysis of diagnostic accuracy and clinical decision-making.

Objective  To evaluate the diagnostic accuracy of clinical evaluation and cross-sectional imaging modalities such as ultrasound and computed tomography for patients with suspected colonic diverticulitis and to determine the value of these examinations in clinical decision-making. Method  A prospective analysis was conducted of 802 consecutive patients that presented with abdominal pain at the emergency department. Initial clinical diagnoses and management proposals were compared to the final diagnoses and therapeutic strategies for all patients. Results  Fifty-seven patients were identified with colonic diverticulitis as the final diagnosis. The positive and negative predictive values for the clinical diagnosis of colonic diverticulitis were 0.65 and 0.98 respectively. Additional cross-sectional imaging had a positive and negative predictive value of respectively 0.95 and 0.99 or higher. These additional examinations led to a correct change of the initial clinical diagnosis in 37% of the patients, and a change in management in only 7%. Conclusion  The accuracy of the clinical diagnosis for colonic diverticulitis is low. Ultrasound and computed tomography have superior diagnostic accuracy but these examinations rarely change the initial management proposal.