Association of heparin-induced skin lesions, intracutaneous tests, and heparin-induced IgG

Background: Cutaneous heparin-induced allergic reactions to subcutaneous he parin may begin 2-5 days after administration. The relation of the delayed- type hypersensitivity and a systemic immunologic response is controversial. The present investigation aimed to analyze the occurrence of thromboemboli c complication, pathologic heparin-induced platelet activation (HIPA), and the presence of circulating heparin-induced IgG in patients with heparin-in duced skin reactions. Methods: Intracutaneous tests, HIPA assay, and heparin-heparin IgG antibodi es were performed in nine patients with heparin-induced skin lesions. Results: Six of eight patients showed positive intracutaneous tests to hepa rin and to four low-molecular-weight heparins. Three of six heparin-positiv e patients presented hypersensitivity to a heparinoid, too. Two of three pa tients had a positive HIPA test and elevated heparin-induced IgG antibodies . Both patients developed complications presenting as heparin-induced skin necrosis or arterial thrombosis. Two of nine patients were treated with dan aparoid, 4/9 patients received r-hirudin, and 1/9 received oral coumarin. I n 2/9 patients, anticoagulant therapy was stopped, but these patients will receive r-hirudin if indicated. Conclusions: On the basis of the coincidence of local and systemic hyperrea ctivity to heparin and danaparoid, patients with heparin-induced skin lesio ns should receive r-hirudin, a nonheparin compound, for anticoagulant treat ment.