A Case of Hemophagocytic Lymphohistiocytosis following Refractory Kawasaki Disease

Introduction Hemophagocytic lymphohistiocytosis (HLH) is a systemic inflammatory disorder characterized by uncontrolled histiocytic proliferation, hemophagocytosis, macrophage activation, and up-regulation of inflammatory cytokines (Grom AA., Current opinion in rheumatology 2003; 15: 587–590). HLH is usually divided into two types: primary (familial) HLH and secondary (reactive) HLH. Primary HLH is associated with primary immune deficiencies in which specific gene mutations play an important role, such as perforin defects.