Derivation of a T2-weighted MRI total colonic inflammation score (TCIS) for assessment of patients with severe acute inflammatory colitis-a preliminary study

Objective To derive an MRI score for assessing severity, therapeutic response and prognosis in acute severe inflammatory colitis. Methods Twenty-one patients with acute severe colitis underwent colonic MRI after admission and again (n=16) after median 5 days of treatment. Using T2-weighted images, two radiologists in consensus graded segmental haustral loss, mesenteric and mural oedema, mural thickness, and small bowel and colonic dilatation producing a total colonic inflammatory score (TCIS, range 6-95). Pre- and post-treatment TCIS were compared, and correlated with CRP, stool frequency, and number of inpatient days (therapeutic response marker). Questionnaire assessment of patient worry, satisfaction and discomfort graded 1 (bad) to 7 (good) was administered Results Admission TCIS correlated significantly with CRP (Kendall's tau=0.45, 95% confidence interval [CI] 0.11-0.79, p=0.006), and stool frequency (Kendall's tau 0.39, 95% CI 0.14-0.64, p=0.02). TCIS fell after treatment (median [22 range 15-31]) to median 20 [range 8-25], p=0.01. Admission TCIS but not CRP or stool frequency was correlated with length of inpatient stay (Kendall's tau 0.40, 95% CI 0.11-0.69, p=0.02). Patients reported some discomfort (median score 4) during MRI. Conclusions MRI TCIS falls after therapy, correlates with existing markers of disease severity, and in comparison may better predict therapeutic response.