| Abstract: | A case of iso-immune neonatal thrombocytopenic purpura caused by a maternal, complement fixing, platelet iso-antibody, anti-PlGrLyB1, is reported. The problems concerning the diagnosis of this disease are discussed. Although the PlGrLyB1-antigen is known to be present on both platelets and leukocytes, and though accordingly the mother's blood contained strong leukocyte agglutinins no leukocytopenia was observed in the patient. The reasons for this observation are discussed. No platelet antibody could be demonstrated in the patient's blood, but the maternal antibody belonged to the γG globulins and was thus placenta-permeable. Evidence is presented of a gene dosage effect of the PlGrLyB1-gene among family members. |
