- Severe combined immunodeficiency All ages with histocompatible sibling donors or with other donors OR Wiskott Aldrich syndrome All ages with histocompatible sibling donors or with other donors OR X-linked CD40 ligand deficiency All ages with histocompatible sibling donors OR Under 5 years of age with donors other than histocompatible siblings OR Other primary immunodeficiencies without manifestations of hemophagocytosis All ages with histocompatible sibling donors or with other donors OR Hemophagocytic lymphohistiocytosis (HLH) Familial erythrophagocytic lymphohistiocytosis (FEL), familial HLH (FHLH), recurrent virus-associated hemophagocytic syndrome (VAHS) All ages with related or unrelated donors OR Chediak Higashi syndrome All ages with related or unrelated donors OR X-linked lymphoproliferative syndrome All ages with related or unrelated donors OR Other primary immunodeficiencies with complication of hemophagocytosis All ages with related or unrelated donors OR Severe progressive Langerhans cell histiocytosis All ages with related or unrelated donors