Frequency of computed tomography scans in Crohn's disease patients in the emergency department

Crohn's Disease patients are often subject to repeat computed tomography (CT) upon presentation to the emergency departments (ED). Due to early age of diagnosis and increase in ED visits, they can be exposed to substantial radiation posing long term increased risk of malignancy. In this retrospective study, we assess frequency of CT scans in the ED, urgent findings on CT, and patient characteristics correlating with multiple scans. We hope to identify predictive factors for urgent findings and for negative CT scans.

Six-hundred-and-sixty previously diagnosed Crohn's patients from four gastroenterology practices presented to three hospitals between April 15, 2015 and December 31, 2018 for 2473 total encounters. Patients were identified and cross-referenced with a radiology database search generating 1778 CT scans performed. Data was analyzed for presence of findings and demographics.

CT scans were performed in 72% of encounters. There was a skewed distribution of CT scans (skew = 3.30), with 41% receiving only 1 scan, 43% receiving 2-4, and 16% receiving >5; the maximum was 24 scans for 1 patient. Positive findings including obstruction, perforation, or abscess were found in 28.5% of scans. Patients with barriers to healthcare had an increased rate of ED visits and imaging findings.

Radiation exposure in Crohn's patients is higher than that of the general population, owing to multiple CT scans often performed acutely in the ED. Factors we assessed could not reliably predict urgent findings on CT and a significant percentage of patients had urgent findings. However, we identified a group with multiple CTs associated with barriers to healthcare.