Gevork Nshan Mnatzakanian MD, Presenter: Nothing to Disclose

Arthur Harold Zalev MD, Abstract Co-Author: Nothing to Disclose

Anish Kirpalani MD, Abstract Co-Author: Nothing to Disclose

Samir C Grover, Abstract Co-Author: Nothing to Disclose

Errol Colak MD, Abstract Co-Author: Nothing to Disclose

Computed tomography enterography (CTE) has emerged as a potential noninvasive technique for imaging the small bowel. However, the role of CTE in evaluating the cause of obscure gastrointestinal bleeding (OGIB) has not been well established. To date, there are no studies which have looked at the efficacy of CTE in diagnosing OGIB in an inpatient population. We evaluated the diagnostic performance of CTE in diagnosing OGIB and long-term outcomes based on negative CTE results in an inpatient population.

A total of 107 consecutive inpatients underwent CTE between January, 2008 and January, 2011 at St. Michael’s Hospital. 39 patients were excluded from the study for indications unrelated to OGIB. 9 patients were excluded for insufficient follow-up/death. All CTE examinations were interpreted by 2 radiologists with at least 6 mo experience in CTE interpretation. The diagnostic performance of CTE was assessed using the results of endoscopic and other imaging examinations, surgery, and clinical follow-up as the reference standard. All patients with a negative CTE examination had at least 1 year of follow-up data. A recurrent bleeding episode after CTE was defined as clinical evidence of bleeding or haemoglobin drop >20 g/L at least 30 days after the index bleed.

Among the 59 inpatients included in the study, CTE correctly identified a lesion in 24 inpatients (40.7%). The overall rebleeding rate in patients with a negative CTE was 41.2%. The sensitivity, specificity, positive predictive value, and negative predictive value of CTE were 63.2% (24 of 38), 95.2% (20 of 21), 96.0% (24 of 25), and 58.8% (20 of 34).

CTE has a potential role in the evaluation of OGIB in an inpatient population. Despite the limited sensitivity, positive CTE findings can reliably indicate the true source of OGIB. However, a negative CTE result in an inpatient population should warrant further investigations to identify a source of bleeding. The diagnostic performance of CTE in diagnosing OGIB in an inpatient population is similar to that seen in outpatient population studies based on review of the existing literature.

In an inpatient population, a positive CT enterography reliably indicates the true source of an OGIB, however a negative study warrants further investigation due to a high rebleeding rate.

Mnatzakanian, G, Zalev, A, Kirpalani, A, Grover, S, Colak, E, CT Enterography in the Setting of Obscure Gastrointestinal Bleeding in an Inpatient Population.  Radiological Society of North America 2012 Scientific Assembly and Annual Meeting, November 25 - November 30, 2012 ,Chicago IL. http://archive.rsna.org/2012/12026297.html