We read with great interest the recent study by Hyams et al1 evaluating the risk of malignancy or hemophagocytic lymphohistiocytosis (HLH) in pediatric patients with inflammatory bowel disease (IBD) treated with infliximab. Although the authors demonstrated no increased risk of malignancy or HLH among pediatric patients treated with infliximab when evaluated by standardized incidence ratios, the use of thiopurines was associated with an increased risk of malignancy and HLH. Although we appreciate the significance of any increased risk for development of malignancy or lymphoproliferative disease among pediatric patients, we were very intrigued by the overall rarity of HLH and malignancy cases particularly as these conditions relate to exposure to Epstein–Barr virus (EBV).