Delayed-type hypersensitivity and cross-reactivity to heparins and danaparoid: a prospective study
Research article published in Dermatologic surgery : official publication for American Society for Dermatologic Surgery [et al.] (2001)
Abstract
BACKGROUND: Delayed-type hypersensitivity (DTH) reactions in patients receiving heparin may occur with both unfractionated (UFHs) and low molecular weight heparins (LMWHs). Skin testing is a clue to detect tolerated heparin or heparinoid preparations for further treatment. OBJECTIVE: To study in vivo cross-reactivity between LMWHs, UFHs, and danaparoid by skin testing in patients with suspected DTH to heparin. METHODS: Patients who fulfilled the criteria for the diagnosis of suspected heparin allergy were involved in a prospective study after informed consent. Patients presented with or had a history of typical erythematous plaques at the heparin injection sites. Skin testing was performed by subcutaneous injections of heparin (300-500 IU anti-Xa activity) and danaparoid (375 IU, eight patients). Desirudin (27,000 IU) was tested in three patients. We read skin reactions after 24, 48, and 96 hours and after 7 days. RESULTS: Fourteen female and 4 male patients were included in our series. Erythematous plaques had been reported or developed after 14-35 days in patients during first-time heparin treatment and after 2-10 days in reexposed patients. Positive skin test results were seen in 15 of 18 (83.3%) patients. Of these, 11 (73.3%) showed cross-reactivity between heparins and/or danaparoid. Six patients reacted to LMWHs only, nine patients to both LMWHs and UFHs. Danaparoid was tolerated in six of eight patients; desirudin was tolerated in all three patients tested. CONCLUSIONS: DTH to heparins is characterized by considerable cross-reactivity between LMWHs, UFHs, and danaparoid. UFHs may be tolerated even if LMWHs are not. Subcutaneous testing of a panel of heparins, danaparoid, and desirudin (hirudin) is recommended to determine acceptable treatment options for patients allergic to specific heparins.
Abstract sourced from PubMed (NCBI) for the cited record. See the original publication for the authoritative version.
Summary
Peer-reviewed research on anticoagulant and antithrombotic drug development relevant to leech-derived and synthetic compounds. Indexed in PubMed and verified against the NCBI record.
Why This Matters for Hirudotherapy
This prospective skin-testing study of 18 patients with suspected delayed-type hypersensitivity to heparin found positive reactions in 15 (83.3%) with extensive cross-reactivity among low-molecular-weight heparins, unfractionated heparins, and danaparoid, while danaparoid was tolerated in 6 of 8 patients and desirudin (recombinant hirudin) was tolerated in all 3 patients tested, leading the authors to recommend testing a panel including desirudin to find acceptable anticoagulants for heparin-allergic patients. This is directly pertinent to hirudotherapy's scientific narrative because desirudin is a recombinant form of hirudin, the prototypical anticoagulant of the medicinal-leech secretome, and the report illustrates a clinical niche where a hirudin-based agent succeeded as an alternative when heparins were not tolerated. The caveats are that this is a small prospective case series of 18 patients with only 3 desirudin exposures, testing the recombinant drug rather than whole-leech therapy, so it supports the value of hirudin pharmacology in selected heparin-allergic patients but does not by itself establish leech-therapy efficacy or safety.
Citation
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