title: Transient familial haemophagocytic lymphohistiocytosis reactivation post-CD34 haematopoietic stem cell transplantation.
abstract: Familial haemophagocytic lymphohistiocytosis (FHLH) is a genetic disorder caused by defective lymphocyte cytotoxicity, resulting in impaired lymphocyte homeostasis and macrophage infiltration of solid tissues and bone marrow, with extensive haemophagocytosis. It is invariably fatal unless treated by allogeneic haematopoietic stem cell transplantation (HSCT). In a retrospective analysis of 11 cases of FHLH, transplanted in one centre between January 1999 and December 2003, it was found that host T cell expansion occurred early after HSCT in a setting of a viral infection (cytomegalovirus and Epstein-Barr virus respectively) in two cases who received T cell-depleted HSCT. Transient recurrence of clinical and biological manifestations of FHLH was observed, despite evidence for donor cell engraftment. Secondary development of donor T cells led to stable mixed chimaerism and sustained remission of FHLH. Detection of host-derived T cells soon after HSCT in a patient with FHLH should thus not mistakenly be taken as a manifestation of graft rejection.
authors.affiliation: Unité d'Immunologie-Hématologie Pédiatrique, Hôpital Necker-Enfants Malades, Paris, France.
authors.forename: H
authors.initials: H
authors.lastname: Almousa
authors.forename: M
authors.initials: M
authors.lastname: Ouachée-Chardin
authors.forename: C
authors.initials: C
authors.lastname: Picard
authors.forename: I
authors.initials: I
authors.lastname: Radford-Weiss
authors.forename: S
authors.initials: S
authors.lastname: Caillat-Zucman
authors.forename: M
authors.initials: M
authors.lastname: Cavazzana-Calvo
authors.forename: S
authors.initials: S
authors.lastname: Blanche
authors.forename: G
authors.initials: G
authors.lastname: de Saint Basile
authors.forename: F
authors.initials: F
authors.lastname: Le Deist
authors.forename: A
authors.initials: A
authors.lastname: Fischer
mesh_terms: D018952:Antigens, CD34; D049109:Cell Proliferation; D018380:Hematopoietic Stem Cell Transplantation; D015616:Histiocytosis, Non-Langerhans-Cell / Q000276:immunology*; D006801:Humans; D007223:Infant; D008297:Male; D011184:Postoperative Period; D012008:Recurrence; D012189:Retrospective Studies; D013601:T-Lymphocytes / Q000473:pathology; D018183:Transplantation Chimera; D014184:Transplantation, Homologous
chemical_list: D018952:Antigens, CD34