Search in the Abstract Database

Search Abstracts 2011

* = Presenting author

P072. Diagnostic medical radiation in inflammatory bowel disease: Primum non-nocere?

R.O. Butcher, E. Nixon, C. Robertson, R. Filobbos, J.K. Limdi

Pennine Acute Hospitals, Manchester, United Kingdom

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

The aim of our study was to quantify radiation exposure among patients with IBD.

Materials and Methods: We conducted a retrospective review of 200 consecutive patients attending IBD clinics at our hospital.

Clinical data including demographic data, disease characteristics and current and previous therapy were obtained from case note and electronic patient record review. All incidences of diagnostic medical radiation from initial diagnosis with IBD until 30 June 2010 inclusive were recorded from case note and computerised radiology database system review. The radiation dose for each procedure was obtained from published tables from the Royal College of Radiologists, UK. Effective dose for each procedure was calculated by multiplying this value by the number of procedures during the study period. The sum of doses received was the cumulative effective dose.

Results: Eighty-eight of the 200 IBD patients reviewed were female, 112 were male. The median age was 50 (Range 19–88) and mean disease duration 10.3 years. Eighty-two patients had Crohn's disease, 110 patients had ulcerative colitis and 8 patients had an indeterminate colitis.

The mean and median cumulative effective radiation doses were 10.02 mSv and 5.07 mSv respectively. A cumulative radiation dose greater than 10 mSv was seen in 39.5% (79) patients and greater than 25 mSv in 10.5% (21) patients. In 3 patients the cumulative effective dose was greater than 50 mSv. Crohn's disease was associated with a higher cumulative effective dose with exposure to greater than 10 mSv in 62.2%, greater than 25 mSv in 18.3% and greater than 50 mSv in 3.7% of patients respectively.

CT imaging accounted for 40% and barium studies for 36% of the total cumulative effective dose exposure. Seventeen of these patients had small bowel magnetic resonance studies in the last 2 years as an alternative to ionising radiation procedures.

Conclusion: Our study has demonstrated that patients with IBD, in particular those with Crohn's disease are exposed to significant amounts of diagnostic medical radiation in their lifetime. The increased risk of cancer from cumulative radiation coupled with the inherent risk of colorectal malignancy in long standing IBD and the potential for immunomodulator drugs such as azathioprine to increase the risk of cancers (eg. lymphoma) is of great clinical and public health concern. Clinicians must remain vigilant to these risks when evaluating patients with IBD and radiation exposure should be minimised by the judicious use of imaging after appropriate discussion of cases with radiologists. Where possible alternative modalities such as intestinal ultrasound and magnetic resonance imaging should be preferred.