Other monogenic diseases that produce HLH are Chédiak-Higashi syndrome (LYST), Griscelli syndrome type 2 (RAB27A), Hermansky-Pudlak syndrome (AP3B1), X-linked lymphoproliferative syndrome (XLP)-1 (SH2D1A), and XLP-2 (XIAP) (19). This evidence concerns the gene SH2D1A and hemophagocytic syndrome.