Feto-maternal alloimmune thrombocytopenia due to HPA-5b incompatibility: a case report.

Feto-maternal alloimmune thrombocytopenia (FMAIT) results from the maternal production of antibodies against fetal platelets with incompatible antigens inherited from the father. We present a case where this condition was diagnosed prenatally without previously affected siblings. The severe fetal thrombocytopenia was due to anti-HLA-5b maternal alloantibodies. This was treated successfully by intravenous immunoglobulins. Our case reflects that FMAIT due to anti-HPA-5b may be severe and may be corrected successfully with intravenous immunoglogulins.