Studies on platelets: XXVIII: acute thrombocytopenic purpura due to lidocaine (Xylocaine)-mediated antibody. Report of a case.

A patient developed severe thrombocytopenia three days after the administration of lidocaine (Xylocaine) for dental extractions. Petechial bleeding and thrombocytopenia regressed promptly, probably aided by treatment with adrenocorticotropic hormone (ACTH) and prednisone. The patient is well one year after her experience and has received other drugs with impunity. The thrombocytopenia appeared related to the presence of a specific antibody, predominantly immunoglobulin M (IgM), heat labile, in the patient's plasma and serum. The antibody was lytic in action and needed complement. It probably coupled to the drug, forming an antigen-antibody complex able to fix itself to and cause the lysis of platelets. Thrombocytopenia was induced with the parenteral administration of a small dose of lidocaine to the patient. This case may represent the first recorded example of hematologic complication related to the use of lidocaine.