[Fondaparinux and lepirudin as therapeutic alternatives in a disseminated eczematous skin reaction to low-molecular-weight heparin].

Low-molecular-weight heparins are obtained by depolymerization of conventional heparin; these heparins are part of the anticoagulant armamentarium and are widely used as therapy or prophylaxis in thromboembolic conditions. They are used at the initiation of long-term oral anticoagulant therapy and are the treatment of choice for the substitution of oral therapy before invasive diagnostic or therapeutic procedures. Reactions such as ecchymoses are commonly observed at the injection sites; eczematous plaques are seen less often. We present a patient who developed an eczematous skin reaction related to Clexane (enoxaparin); intradermal tests revealed delayed-type hypersensitivity and subcutaneous challenge confirmed cross-reactivity to unfractionated heparin and other low-molecular-weight heparins available at our hospital. An 80-year-old woman with paroxysmal atrial fibrillation and a double aortic valve lesion was receiving oral anticoagulation with Sintrom (acenocoumarol). She was admitted for cardiac catheterization (as part of the workup for valve repair) and the oral anticoagulant was switched to subcutaneous Clexane at a dose of 40 mg/24 h. Four days after starting the new treatment, pruritic erythematous papules appeared in the periumbilical region, coinciding with the sites of injection, and tended to coalesce to form plaques (Figure 1); dyshidrosiform lesions were also observed on the palms (Figure 2). Following 48 hours of replacement therapy with intravenous sodium heparin, the lesions became disseminated. Skin biopsy showed spongiosis with mild eosinophilia. The patient recalled a similar acute local reaction when she was admitted on a previous occasion due to the onset of atrial fibrillation and received subcutaneous Clexane prior to oral anticoagulation; the reaction resolved after the oral therapy was started. Because a delayed-type hypersensitivity reaction to enoxaparin was suspected, heparin was discontinued and