Letter: Thiopurines the Silent Workhorse for Many Patients After a Flare of Ulcerative Colitis. Authors' Reply

We thank Drs Sward and Segal for their interest in our paper and their insightful comments [1, 2]. We agree that the patients requiring hospitalisation for acute severe ulcerative colitis represent a distinct subgroup from those with moderate to severe ulcerative colitis [3]. While we agree that, for the purpose of assessing therapeutic efficacy of an agent or strategy, it is prudent to consider these categories separately, the current trial only enrolled individuals who had responded initially to steroids (intravenous or oral). Indeed, all patients hospitalised for ASUC were started on thiopurines as is usual. In addition, our randomisation was stratified for the presence or absence of ASUC. Since only a limited sigmoidoscopy is often suggested in patients being evaluated to severe disease (ASUC), the disease extent may not be available in every patient [3]. However, this number was rather small. In the future, the inclusion of intestinal ultrasound in such trials may help determine the extent of bowel involvement at the commencement of the study even in absence of a full colonoscopy [4]. We also agree with some reports suggesting differences in outcomes with intravenous methylprednisolone versus hydrocortisone; however, all of the hospitalised patients in the present study received methylprednisolone (although the protocol allowed either of the two). In addition, the doses of oral mesalamine were similar in both groups, as were the number of patients on oral and/or rectal mesalamine. Although thiopurine metabolite measurements are used to optimise thiopurine therapy, we have not performed them because the facility is not available at our centre [5, 6]. We have performed pharmacogenetic testing in the reported number of patients. We do agree that the findings of the study need to be contextualised appropriately and interpreted in light of the above considerations. Ankit Kumar: writing – review and editing, conceptualization. Amol Patil: conceptualization, writing – review and editing. Vishal Sharma: conceptualization, writing – review and editing. The authors have nothing to report. The authors declare no conflicts of interest. This article is linked to Kumar et al papers. To view these articles, visit https://doi.org/10.1111/apt.70509 and https://doi.org/10.1111/apt.70617. Data sharing not applicable to this article as no datasets were generated or analysed during the current study.