Department of Dermatology and Allergology Biederstein, Technische Universität München, Munich, Germany.
Curr Opin Allergy Clin Immunol. 2011 Aug;11(4):326-31. doi: 10.1097/ACI.0b013e32834877c3.
Radiographic contrast media (RCM) are increasingly used in modern diagnostic medicine. Hypersensitivity reactions to nonionic RCM still occur in a significant number of exposed patients, because of the increased use of contrasted radiological investigations. Hypersensitivity reactions may be divided into immediate (<1 h of administration) and nonimmediate responses (>1 h). Immediate reactions present with anaphylaxis.
Although described less commonly, anaphylaxis to gadolinium contrast media have been increasingly reported in recent literature. In most patients, immunoglobulin (IgE)-mediated allergy cannot be demonstrated and the underlying mechanism remains unknown. In some patients, positive skin tests, specific IgE antibodies or specific cellular tests have been demonstrated. It may be speculated that more allergic reactions could be described, if more adequate methods were developed. Skin prick tests and intradermal tests with 1 : 10 diluted RCM are specific and confirm the diagnosis of RCM hypersensitivity.
There are not enough data yet about the value of skin tests for the selection of a 'well tolerated' RCM. Premedication of previous reactors is common among radiologists. However, breakthrough reactions are a concern and physicians should not rely on the efficacy of pharmacological premedication. Instead, radiologists should be prepared to treat severe RCM-induced allergic reactions in their practice.
放射性对比剂（RCM）在现代诊断医学中应用日益广泛。由于放射影像学检查的广泛应用，非离子型 RCM 的过敏反应仍在大量暴露的患者中发生。过敏反应可分为即刻（给药后<1 小时）和非即刻（给药后>1 小时）反应。即刻反应表现为过敏反应。
尽管描述较少，但在最近的文献中越来越多地报道了钆造影剂的过敏反应。在大多数患者中，不能证明免疫球蛋白（IgE）介导的过敏反应，其潜在机制尚不清楚。在一些患者中，已证明存在阳性皮肤试验、特异性 IgE 抗体或特异性细胞试验。如果开发出更合适的方法，可能会描述更多的过敏反应。用 1：10 稀释的 RCM 进行皮肤点刺试验和皮内试验具有特异性，并可确诊 RCM 过敏。
目前关于皮肤试验选择“耐受性良好”的 RCM 的价值的数据还不够。放射科医生对以前的反应者进行预用药很常见。然而，突破性反应令人担忧，医生不应依赖药物预用药的疗效。相反，放射科医生应该在实践中准备好治疗严重的 RCM 诱导的过敏反应。
