Oya Seiro, Nakamori Tomoki, Kinoshita Hirohisa
Department of Emergency and Critical Care Medicine Yokohama Rosai Hospital Yokohama Kanagawa Japan.
Acute Med Surg. 2014 May 19;1(4):228-233. doi: 10.1002/ams2.48. eCollection 2014 Oct.
Anaphylaxis is a systemic allergic reaction that potentially causes death. Most anaphylactic reactions are uniphasic, but some cases may be biphasic or protracted. However, these clinical epidemiology concepts are unfamiliar in Japan. Therefore, we have investigated the incidences and characteristics of patients with biphasic and protracted anaphylaxis.
We retrospectively evaluated patients with anaphylaxis in a single emergency medical center located in Yokohama, Japan from April 2009 to March 2012. We analyzed the incidences and characteristics of patients with biphasic and protracted anaphylaxis who needed to be admitted.
A total of 253 patients were diagnosed with anaphylaxis and 114 patients needed to be admitted. Of the 114 patients, 103 (90.4%) were uniphasic, 7 (6.1%) were biphasic and 4 (3.5%) were protracted anaphylaxis. The most common antigens were foods and drugs. The median onset of a biphasic reaction was 8 h and dermatologic symptoms were mostly observed. Regarding severity, mild symptoms were seen in four cases, similar symptoms to the initial reaction were seen in two cases, and only one case was severe. The duration of protracted anaphylaxis varied from 2 to 8 days.
The incidence of biphasic and protracted anaphylaxis in inpatients was 6.1% and 3.5%, respectively. The median onset of biphasic reaction was 8 h, and most symptoms were mild or similar to the initial reaction. We suggest that patients with anaphylaxis need an 8-h and ideally a 24-h observation period in order to monitor possible biphasic reactions. The duration of protracted anaphylaxis was up to 8 days.
过敏反应是一种可能导致死亡的全身性过敏反应。大多数过敏反应是单相的，但有些病例可能是双相或迁延性的。然而，这些临床流行病学概念在日本并不为人熟知。因此，我们对双相和迁延性过敏反应患者的发病率及特征进行了调查。
我们回顾性评估了2009年4月至2012年3月间在日本横滨一家急救医疗中心就诊的过敏反应患者。我们分析了需要住院治疗的双相和迁延性过敏反应患者的发病率及特征。
共有253例患者被诊断为过敏反应，其中114例需要住院治疗。在这114例患者中，103例（90.4%）为单相过敏反应，7例（6.1%）为双相过敏反应，4例（3.5%）为迁延性过敏反应。最常见的过敏原是食物和药物。双相反应的中位发作时间为8小时，主要表现为皮肤症状。在严重程度方面，4例症状较轻，2例症状与初始反应相似，仅1例症状严重。迁延性过敏反应的持续时间为2至8天。
住院患者中双相和迁延性过敏反应的发病率分别为6.1%和3.5%。双相反应的中位发作时间为8小时，大多数症状较轻或与初始反应相似。我们建议过敏反应患者需要观察8小时，理想情况下观察24小时，以监测可能出现的双相反应。迁延性过敏反应的持续时间长达8天。
