title: Pseudothrombocytopenia masking true thrombocytopenia.
abstract: Pseudothrombocytopenia owing to platelet clumping is usually associated with blood specimens anticoagulated with EDTA. It may also be seen if specimens possessing IgM cold agglutinins are processed at room temperature. A patient with a temperature-independent, EDTA-independent agglutinin is reported whose pseudothrombocytopenia was masking true thrombocytopenia. A technique for blood collection when evaluating similar cases is described.
mesh_terms: D000368:Aged; D000373:Agglutinins / Q000276:immunology; D001327:Autoimmune Diseases / Q000175:diagnosis*; D001778:Blood Coagulation Disorders / Q000175:diagnosis*; D001792:Blood Platelets / Q000276:immunology*; D001800:Blood Specimen Collection; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D007075:Immunoglobulin M / Q000276:immunology; D010974:Platelet Aggregation; D010976:Platelet Count; D013921:Thrombocytopenia / Q000175:diagnosis*
chemical_list: D000373:Agglutinins; D007075:Immunoglobulin M