Radiation exposure in patients with inflammatory bowel disease--primum non nocere?

Patients with Inflammatory Bowel disease (IBD) are frequently exposed to diagnostic medical radiation for the diagnosis and evaluation of their disease. Despite increasing awareness of the potentially serious downstream effects, few studies have quantified radiation exposure in IBD patients.

We conducted a retrospective review of 280 consecutive patients attending IBD clinics at our hospital. All incidences of diagnostic medical radiation from initial diagnosis until 30 June 2010 inclusive were recorded. The radiation dose for each procedure was obtained from standardized tables and the effective dose for each procedure calculated by multiplying this value by the number of procedures during the study period. The sum of doses received was the cumulative effective dose.

The mean and median cumulative effective radiation doses were 10.17 mSv and 4.12 mSv respectively. Crohn's disease patients had significantly higher cumulative effective radiation exposure than UC patients (p < 0.001) with exposure exceeding 10 mSv in 58.3%, 25 mSv in 18.1% and 50 mSv in 6.3%, respectively. Smoking status, disease duration, and previous surgery were significant predictors for increased radiation exposure even after adjusting for other predictors. 47 small bowel magnetic resonance (MR) studies were undertaken as an alternative to ionising radiation in the last 3 years.

Patients with IBD, particularly those with Crohn's disease, are exposed to significant amounts of diagnostic medical radiation in their lifetime. Clinicians must remain vigilant to the risk of cumulative radiation when evaluating these patients and consider non-ionizing alternatives such as intestinal ultrasound and MR imaging where clinically appropriate.