Prospective validation of AIIMS index as a predictor of steroid failure in patients with acute severe ulcerative colitis

Optimal outcomes in acute severe ulcerative colitis (ASUC) are related to time-bound management based upon early prediction of response to intravenous (IV) steroids. In an earlier study, we described the All India Institute of Medical Sciences (AIIMS) index (baseline Ulcerative Colitis Endoscopic Index of Severity [UCEIS] ≥ 7 and day 3 fecal calprotectin [FCP] > 1000 μg/g) for predicting failure of IV steroids. The current study is designed to validate this index in a prospective cohort.

IV steroid-naïve patients with ASUC, satisfying Truelove and Witts' criteria, hospitalized from August 2018 to July 2019 were included. Patients' assessment included baseline sigmoidoscopy, day 1 and 3 FCP, hemogram, biochemistry and day 3 C-reactive protein. All patients received IV steroids, and the primary outcome was steroid failure, defined as the need for colectomy or rescue therapy with cyclosporine (CYC)/infliximab (IFX) during admission.

Of the 47 patients, eight were excluded (four received steroids outside, two were directly taken for surgery/infliximab therapy, one had toxic megacolon, and one had infectious colitis), and 39 patients were included (mean age: 36.1 ± 12.6 years, male: 31%). Fifteen patients (38%) failed IV steroid and required rescue therapy (IFX: 9, CYC: 2, Colectomy: 3, IFX followed by colectomy: 1). On univariate analysis, UCEIS ≥ 7 at baseline (p = 0.006), day 1 FCP (p = 0.03), day 3 FCP > 1000 μg/g (p = 0.001), Oxford criteria (p = 0.04) and AIIMS index (p < 0.001) were significantly different between steroid responders and steroid failures. On multivariate analysis, day 3 FCP > 1000 μg/g (odds ratio (odds ratio (OR)= 6.4;(95% CI =2.2-196.1) and baseline UCEIS ≥ 7 (OR) = 10.1;(95% CI = 2.1-80.2) were independent predictors. The AIIMS index predicted steroid failure with a better specificity (100% vs. 83%, p = 0.04) and positive predictive value (100% vs. 64%, p = 0.03) than Oxford criteria.

AIIMS index has been validated in 39 prospective ASUC patients as an effective early predictor of steroid failure (sensitivity = 53%, specificity = 100%).