Utility of emergency department use of abdominal pelvic computed tomography in the management of Crohn's disease

Goal: The primary aim of this study was to determine predictors of clinically significant computed tomography (CT) scans, paying particular attention to findings of previous CT scans. Background: Use of CT to assess patients with Crohn's disease (CD) in the Emergency Department (ED) is both costly and exposes patients to high levels of ionizing radiation while not clearly improving outcomes. Study: Patients with CD who underwent CT scan in the Emergency Department from 2008 to 2011 at a tertiary referral center were assessed for clinically significant findings. A multivariable generalized estimating equation model with logit link and exchangeable working correlation structure was constructed to assess for independent predictors of CT scans with clinically significant findings. Results: A total of 118 patients with CD underwent 194 CT scans. Ninety-two of 194 (47%) CT scans demonstrated clinically significant findings. Predictors of clinically significant CT scans included ileal disease involvement [odds ratios (OR) 3.47, P=0.01] and white blood cell count >12 (OR 2.1, P=0.03). Most notably, patients with a CT scan without clinically significant findings performed in the preceding month were significantly less likely to have a clinically significant CT scan (OR 0.23, P=0.005). Conclusions: Patients with CD who had a CT scan without significant findings the month prior are unlikely to have clinically significant CT findings. Ileal disease and an elevated white blood cell are predictive of clinically significant CT scans.