Utility of CT in the emergency department in patients with ulcerative colitis

Computed tomography (CT) is used in the emergency department (ED) for triage of patients with gastrointestinal complaints. Patients with inflammatory bowel disease undergo radiologic studies for gastrointestinal symptoms and are at risk for excessive ionizing radiation exposure; however, the utility of CT in the ED in patients with ulcerative colitis (UC) is not clear. In this study, we assess the frequency and risk factors for clinically significant CT findings in patients with UC in the ED.

We retrospectively reviewed 163 consecutive cases of patients with UC who presented to a tertiary care ED and underwent abdominopelvic CT between June 2008 and December 2011. Using logistic regression, we identified predictors of significant CT findings and derived a model to predict CT scans without clinically significant findings.

Of note, 63.2% (103/163) of CT scans had no clinically significant findings. Less than 2% of scans revealed complications related to UC. Predictors of CT scans without clinically significant findings included rectal bleeding or diarrhea (P < 0.001), use of 5-aminosalicylate (P = 0.011), or immunomodulator (P = 0.032). Alternatively, predictors of clinically significant CT findings included nausea and vomiting (P < 0.001), history of colectomy (P < 0.001), history of abdominal or pelvic surgery (P < 0.001), surgery within 1 month (P < 0.001), age (P = 0.004), elevated white blood cell count (P = 0.003), and no UC medications (P = 0.001).

Most patients with UC who presented to the ED and underwent CT had no clinically significant findings. We devised a model to predict lack of clinically significant CT findings, which may assist in reducing cost and radiation exposure in patients with UC.