Neonatal alloimmune thrombocytopenic purpura associated with sensitization against the platelet-specific antigen Yuk(a).

We report a Japanese newborn who developed alloimmune thrombocytopenia by the antibodies to the newly discovered platelet antigen Yuk(a). The infant recovered uneventfully in 10 days without specific treatment. Antiplatelet alloantibodies in the patient were IgG class detected by mixed passive hemagglutination (MPHA). Family study showed that Yuk(a) antigen was inherited as an autosomal dominant trait. Cases with Yuk(a)-associated alloimmune thrombocytopenia are reviewed.