Sebastian platelet syndrome: a new variant of hereditary macrothrombocytopenia with leukocyte inclusions.
Fechtner syndrome--a variant of Alport's syndrome with leukocyte inclusions and macrothrombocytopenia.
Idiopathic thrombocytopenic purpura is known to be due to platelet sensitization, with autoantibodies leading to platelet destruction in the reticuloendothelial system; peripheral smears may show variable macrothrombocytopenia and autoantibodies to specific surface glycoproteins can be detected by flow cytometry or immunoassay, (95) although diagnosis is largely from clinical findings.
There are several rare macrothrombocytopenia syndromes without neutrophil inclusions, which are generally characterized by either surface glycoprotein abnormalities or platelet functional defects.
Several macrothrombocytopenia disorders are characterized by the presence of neutrophilic inclusions.
The 2 other macrothrombocytopenia disorders with neutrophilic inclusion are Fechtner syndrome and Sebastian syndrome.
Giant platelets observed with macrothrombocytopenia syndromes can give false low platelet counts, because the large platelets may be counted as leukocytes by automated cell counters.
In von Willebrand disease, Glanzmann thrombasthenia, and myeloproliferative disorders, the platelets have typical morphologic features, whereas giant platelets are seen in Bernard-Soulier disease and other macrothrombocytopenia syndromes.