EDTA-dependent pseudothrombocytopenia (PTCP) is the phenomenon of a spurious low platelet count due to EDTA-induced aggregation of platelets. Since the failure to recognize EDTA-dependent PTCP may result in incorrect diagnosis and inappropriate treatment, the recognition of this phenomenon is very important. We report an insidious case of EDTA-dependent PTCP confirmed by supplementation of kanamycin to anticoagulant in a 53-year-old women. Although sodium citrate and heparin usually prevented the aggregation of platelets in EDTA-dependent PTCP patients, these anticoagulants failed in preventing PTCP in our case. EDTA-dependent PTCP was confirmed by the findings that the clumping of platelets on microscopic evaluation was found in EDTA-anticoagulated blood samples, whereas thrombocytopenia and platelet aggregation were not revealed in the sample supplemented with kanamycin.
Antibiotics, Aminoglycoside/*pharmacology ; Anticoagulants/*adverse effects/pharmacology ; Case Report ; Edetic Acid/*adverse effects ; Female ; Human ; Kanamycin/*pharmacology ; Middle Age ; Platelet Aggregation/*drug effects ; Platelet Aggregation Inhibitors/*therapeutic use ; Platelet Count ; Thrombocytopenia/*blood/chemically induced