Clinical significance of platelet alloantibodies detected in immunofluorescence test (neonatal alloimmune thrombocytopenia and post-transfusion purpura).

Three cases of neonatal alloimmune thrombocytopenia and one patient with post-transfusion purpura could be diagnosed only by introducing the platelet immunofluorescence test. Thrombocytopenia was caused by anti-PlA1 platelet alloantibodies detected neither in the agglutination nor by the complement fixation test.