Department of Dermatology, Venereology, and Allergology, University Hospital of Würzburg, Josef-Schneider-Str, 2, Würzburg, 97080, Germany.
Allergy Asthma Clin Immunol. 2013 Jan 10;9(1):1. doi: 10.1186/1710-1492-9-1.
Heparins are one of the most used class of anticoagulants in daily clinical practice. Despite their widespread application immune-mediated hypersensitivity reactions to heparins are rare. Among these, the delayed-type reactions to s.c. injected heparins are well-known usually presenting as circumscribed eczematous plaques at the injection sites. In contrast, potentially life-threatening systemic immediate-type anaphylactic reactions to heparins are extremely rare. Recently, some cases of non-allergic anaphylaxis could be attributed to undesirable heparin contaminants.A 43-year-old patient developed severe anaphylaxis symptoms within 5-10 minutes after s.c. injection of enoxaparin. Titrated skin prick testing with wheal and flare responses up to an enoxaparin dilution of 1:10.000 indicated a probable allergic mechanism of the enoxaparin-induced anaphylaxis. The basophil activation test as an additional in-vitro test method was negative. Furthermore, skin prick testing showed rather broad cross-reactivity among different heparin preparations tested.In the presented case, history, symptoms, and results of skin testing strongly suggested an IgE-mediated allergic hypersensitivity against different heparins. Therefore, as safe alternative anticoagulants the patient could receive beneath coumarins the hirudins or direct thrombin inhibitors. Because these compounds have a completely different molecular structure compared with the heparin-polysaccharides.
肝素是日常临床实践中使用最广泛的抗凝药物之一。尽管肝素的应用广泛，但免疫介导的过敏反应却很少见。其中，皮下注射肝素引起的迟发型反应是众所周知的，通常表现为注射部位的局限性湿疹斑块。相比之下，肝素引起的潜在危及生命的全身性即刻型过敏反应极为罕见。最近，一些非过敏的过敏反应病例可能归因于肝素的不良污染物。一名 43 岁的患者在皮下注射依诺肝素后 5-10 分钟内出现严重的过敏反应症状。皮试测试显示风团和红晕反应，最高稀释度可达 1:10000，表明依诺肝素引起的过敏反应可能是由 IgE 介导的过敏机制引起的。作为额外的体外测试方法，嗜碱性粒细胞活化试验为阴性。此外，皮试测试显示不同肝素制剂之间存在广泛的交叉反应。在本病例中，病史、症状和皮试结果强烈提示患者对不同肝素存在 IgE 介导的过敏反应。因此，作为安全的替代抗凝药物，患者可以选择华法林以外的水蛭素或直接凝血酶抑制剂。因为这些化合物与肝素多糖具有完全不同的分子结构。
