What’s New in ASUC?

Acute severe ulcerative colitis (ASUC), as defined by Truelove and Witts, continues to be considered a medical emergency, with 10% to 25% of patients with UC presenting with ASUC as their index presentation and 20% to 30% experiencing ASUC during the course of the disease.

Intravenous steroids have been the mainstay of therapy for ASUC over the last 60 years; however, approximately 40% of patients with ASUC fail corticosteroid therapy, and traditional criteria are typically used on day 3 to defi ne steroid failure.

Despite the long-standing use of intravenous steroids, physicians have accepted certain failure rates.

Exclusive enteral nutrition (EEN) has been proven effective in adult and pediatric Crohn’s disease, and dietary therapy has an important role in UC.

To augment the response to steroids in ASUC, there is a focus on strategies such as the continued use of intravenous steroids, acknowledging the traditionally accepted failure rates. Additionally, dietary therapy, specifically semi-elemental EEN, is considered as a strategy to augment steroid response.

Assessing the response to medical rescue therapy involves utilizing markers such as CRP/albumin cut-off post-commencement of infliximab, which serves as a predictor of colectomy at 12 months. The CRP/albumin ratio (CAR) on day 3 after infliximab is another marker, with a CAR of 0.47 showing 79% sensitivity, 80% specificity and 94% negative predictive value to predict colectomy at 12 months.

Newer strategies to assess steroid responsiveness include Imaging Ultrasound Score (IUS) and the AIIMS index. The emerging and established role of JAK inhibitors in ASUC is also noted, and there is a recognized need for a clear and effective defi nition for the failure of rescue therapy in ASUC.