[Occurrence of severe, persistent thrombocytopenia following allogeneic bone marrow transplantation, attributable to anti-HPA-1 allo-immunisation of the host].
A 56 year-old, multiparous woman suffering from a myeloproliferative syndrome, who had received multiple red blood cell and platelet transfusions, was the recipient of an allograft of peripheral blood stem cells derived from her HLA-A, B, DR, DQ and DP and ABO identical sister, following myeloablative conditioning. The persistence of severe, isolated thrombopenia resistant to platelet transfusions led to the discovery of anti-HLA class I allo-immunisation. As HLA compatible platelet transfusions did not result in satisfactory platelet increments, we then discovered the simultaneous presence of anti-HPA-1a allo-immunisation. Genotyping of the HPA-1 systems of the patient (HPA-1B/B) and her sister (HPA-1A/B) enabled us to elucidate the mechanism underlying the persistent thrombopenia and the inefficacy of transfusion. In fact, only transfusion of HPA-1B/B platelets (HLA compatible or incompatible) proved to be efficacious. To reduce the level of anti-HPA-1a antibodies, we performed plasmapheresis sessions and used an anti-CD20 monoclonal antibody. It was only on achieving total haematopoietic chimerism, through rapid interruption of the immunosuppression, that we obtained spontaneous normalisation of the platelet count. The present case emphasises the necessity, before undertaking any allograft of haematopoietic stem cells - even if the latter come from a strictly HLA identical member of the family - of performing a search for eventual anti-HPA allo-immunisation.
Parissiadis
A
A
Laboratoire d'histocompatibilité, EFS-Alsace, 10, rue Spielmann, 67065 Strasbourg, France. anne.parissiadis@efs-alsace.fr
Bilger
K
K
Laplace
A
A
Berceanu
A
A
Schwebel
M
M
Froelich
N
N
Cazenave
J-P
JP
Hanau
D
D
Tourne
S
S
Lioure
B
B
D016824:Antigens, Human Platelet / Q000276:immunology*; D016026:Bone Marrow Transplantation / Q000009:adverse effects*; D005260:Female; D006801:Humans; D008875:Middle Aged; D012720:Severity of Illness Index; D013921:Thrombocytopenia / Q000276:immunology*
D016824:Antigens, Human Platelet