Abstract • 138

Since 1989 we have confirmed the diagnosis of FMAIT in 13 cases. Retrospectively, we detected anti-HPA-1a antibodies in half of the cases by the Capture-P-Ready Screen test (Immunocor, USA) and/or the GTI PAK Plus test (Brookfield, Wi). For identification of platelet antibodies the MAIPA (Monoclonal Antibody Immobilization of Platelet Antigen) assay was used. With a panel of eight monoclonal antibodies against different platelet glycoproteins, seven sera of mothers of newborns with FMAIT were examined with the MAIPA assay. Anti-GPIIIa was the most frequent antibody, combined with anti-GPIIb in two cases, and with anti-GPIV and anti-GPIX in one case each.

HPA typing of blood donors by PCR-SSP was used to find suitable platelet donors for neonates and fetuses with FMAIT. The frequency of the HPA gene in 235 randomly selected Czech blood donors was 0.83 and 0.17 for HPA-1a and -b; 0.90 and 0.10 for HPA-2a and -b; 0.59 and 0.41 for HPA 3a and -b; 0.93 and 0.07 for HPA-5a and -b, respectively.

Conclusions: The introduction of the MAIPA assay for platelet antibody identification prompted considerable improvement in the diagnosis of FMAIT. HPA typing by PCR-SSP can help to confirm the diagnosis of FMAIT and contribute to provide compatible transfusion donors for newborns and fetuses with FMAIT