Transient EDTA-dependent pseudothrombocytopenia in a patient with sepsis.

Ethylenediaminetetraacetic acid-dependent pseudothrombocytopenia (EDTA-PTCP) is the phenomenon of a spurious low platelet count due to antiplatelet antibodies that cause platelet clumping in blood anticoagulated with EDTA. We describe a case of EDTA-PTCP that appeared transiently with the development of sepsis. A 50-year-old man underwent Bentall's aortic root replacement for acute aortic dissection with aortic insufficiency. Postoperatively the patient suffered paralytic ileus followed by methicillin-resistant Staphylococcus aureus enteritis and septicemia with endotoxemia. EDTA-PTCP appeared with the development of sepsis, and disappeared with its resolution. To avoid incorrect diagnoses and inappropriate treatment, EDTA-PTCP should always be considered as a possible cause of reported low platelet counts, even in patients with sepsis.