The first Japanese family with Sebastian platelet syndrome

This report describes the first Japanese family diagnosed with Sebastian pl atelet syndrome. Within this family, a B-year-old boy and 3 family members on his paternal side demonstrated thrombocytopenia with giant platelets and inclusion bodies in granulocytes, but the additional clinical features of Alport's syndrome occurring in the Fechtner syndrome were lacking. Light mi croscopy and ultrastructural findings of the leukocyte inclusion bodies dis tinguished these patients from the May-Hegglin anomaly. This family showed consistently higher levels of platelet-associated IgG (PAIgG), while surfac e expression of platelet membrane glycoproteins (GPIIb/IIIa and GPIb) and p lasma glycocalicin levels were within the normal range. Careful observation of the giant platelet and leukocyte inclusion bodies in blood smears may h elp the diagnosis of this rare disease entity. (C) 1999 The Japanese Societ y of Hematology.