Diagnostic accuracy of MRE indices studied for active crohn disease

Magnetic resonance enterography (MRE) indices have high diagnostic sensitivity, but low specificity, for active terminal ileal (TI) Crohn disease (CD), according to a study recently published in the Journal of Crohn’s & Colitis.

Shankar Kumar, M.B.B.S., from University College London, and colleagues examined MRE indices in a multicenter diagnostic accuracy trial among a subset of participants from the METRIC trial who were newly diagnosed or suspected of relapse and had available TI biopsies. The sensitivity and specificity of the simplified MRE index of activity (sMARIA), London, and “extended” London scoring systems for active TI CD were calculated. Data were included for 111 patients (75 newly diagnosed; 36 suspected relapse), of whom 22, 39, 13, and 37 had no CD activity (histological activity index [HAI] = 0), mild CD activity (HAI = 1), moderate CD activity (HAI = 2), and severe CD activity (HAI = 3). Twenty-six radiologists scored MRE datasets.

The researchers found that for active disease (HAI >0), the sensitivity and specificity, respectively, were 83 and 41 percent for sMARIA, 76 and 64 percent for the London score, and 81 and 41 percent for the “extended” London score. For severe CD, the sMARIA had sensitivity and specificity of 84 and 53 percent, respectively.

“This study provides evidence that the sMARIA, London, and ‘extended’ London indices are sensitive for detecting active CD of the TI in a real-world setting,” the authors write. “Specificity is low for all three scores, with the London score having the highest.”

Several authors disclosed financial ties to the biopharmaceutical industry.