Additionally, approximately 50–70% of patients with X-linked lymphoproliferative disease 2 (XLP2), caused by mutations that limit XIAP expression/function, develop hemophagocytic lymphohistiocytosis (HLH) with symptoms that include hyperinflammation and early-onset chronic haemorrhagic colitis [172,173,174,175]. The gene discussed is XIAP; the disease is hemophagocytic syndrome.