Thiopurines have been mainly used to maintain remission in patients with inflammatory bowel disease (IBD) for decades, especially since the landmark placebo-controlled double blind randomized study by Markowitz et al.1 However, adverse events, especially cancer risk, remain a concern.2 The use of thiopurines in Epstein-Barr virus (EBV)–naïve patients with IBD has been questioned owing to the potential risk of hemophagocytic lymphohistiocytosis (HLH).3