Department of Internal Medicine, Clinical Pharmacology and Toxicology Unit, University of Genoa, Genoa, Italy.
J Clin Pharm Ther. 2012 Dec;37(6):733-5. doi: 10.1111/j.1365-2710.2012.01360.x. Epub 2012 May 30.
The most common complication of heparin therapy is bleeding. Allergic reactions to heparin are rare, and the mechanisms are poorly understood. We report on a case of acute systemic reaction after subcutaneous injections of a low-molecular-weight heparin (LMWH) in a patient with a genetic predisposition to thrombotic events and review the literature on heparin-induced acute adverse reaction.
A 57-year-old diabetic, hypertriglyceridemic and hypercholesterolemic man was admitted with a fractured right malleolus sustained while driving. He was prescribed parnaparin sodium 4250 IU subcutaneously once a day. During the third injection, the patient developed widespread pain, sickness and facial rash, followed by a state of stupor (Glasgow Coma Scale 8) and was hospitalized in Neurological Unit. He was found to be a carrier of two genetic mutations (i.e. prothrombin G20210A and MTHFR mutation) associated with an increased risk of thrombotic events. Discontinuation of parnaparin and supportive care led to a sufficient recovery of the patient to be discharged 6 days after admission.
Treatment for heparin-related hypersensitivity reactions is largely supportive and symptomatic. Clinicians should be aware of these rare but potentially serious adverse events. Prothrombin gene mutations are quite common, and guidelines on anticoagulant therapy for affected patients are needed.
肝素治疗最常见的并发症是出血。肝素过敏反应罕见，其机制尚不清楚。我们报告了一名具有血栓形成事件遗传易感性的患者在皮下注射低分子量肝素（LMWH）后发生急性全身反应的病例，并回顾了肝素引起的急性不良反应的文献。
一名 57 岁的糖尿病、高三酰甘油血症和高胆固醇血症患者因驾驶时右脚外踝骨折而入院。他被开了那屈肝素钙 4250IU，每天皮下注射一次。第三次注射时，患者出现广泛疼痛、不适和面部皮疹，随后出现昏迷状态（格拉斯哥昏迷量表 8 分）并被收入神经内科病房。他携带两种与血栓形成事件风险增加相关的基因突变（即凝血酶原 G20210A 和 MTHFR 突变）。停用那屈肝素钙和支持性护理使患者充分恢复，在入院后 6 天出院。
肝素相关性过敏反应的治疗主要是支持和对症治疗。临床医生应意识到这些罕见但潜在严重的不良事件。凝血酶原基因突变很常见，需要为受影响的患者制定抗凝治疗指南。
