Department of Allergy and Clinical Immunology, Iran University of Medical Sciences, Tehran, Iran.
Department of Paediatric, School of Medicine, Sabzevar University of Medical Sciences, Sabzevar, Iran.
Iran J Allergy Asthma Immunol. 2021 Feb 11;20(1):120-124. doi: 10.18502/ijaai.v20i1.5419.
Hereditary angioedema (HAE) is characterized by recurrent attacks of skin and mucosal swelling in any part of the body including the digestive and respiratory tract which generally improve spontaneously within 12-72 hours. The underlying mechanism in HAE is related to bradykinin dysregulation which causes these attacks not to respond to common treatment strategies including epinephrine/corticosteroid or adrenaline. There are several types of HAE with different etiology but with the same clinical picture. Type 1 is due to the deficiency of C1 Inhibitor (C1-INH) protein and type 2 is related to dysfunctional C1-INH protein. The third type of HAE which comprises the minority of cases is associated with the normal amount and function of C1-INH protein. The presented case in this report was a 15-years old girl with a history of spontaneous angioedema attacks from the age of 14. The frequency of attacks was initially every two months but consequently increased to every two weeks after using some hormonal medications for ovarian cyst. Each episode has lasted around 10 days without any symptoms in between. Complement studies including C4, C1q, and C1-INH protein, both quantitative and qualitative, were reported as normal. A genetic assessment revealed a mutation in the exon 9 on the gene related to factor XII, hence the diagnosis of HAE type 3 was confirmed. This was a rare type of angioedema with normal amount and function of C1-INH protein which is predominantly seen in women during periods of imbalanced estrogen increments like pregnancy, lactation, and menopause, and hence it is responsive to hormonal manipulation strategies such as the use of progesterone containing medications.
遗传性血管性水肿 (HAE) 的特征是身体任何部位反复发作皮肤和粘膜肿胀，包括消化道和呼吸道，这些症状通常会在 12-72 小时内自发改善。HAE 的潜在机制与缓激肽失调有关，这导致这些发作不能对包括肾上腺素/皮质类固醇或肾上腺素在内的常见治疗策略产生反应。HAE 有几种类型，病因不同，但临床表现相同。1 型是由于 C1 抑制剂 (C1-INH) 蛋白缺乏引起的，2 型与 C1-INH 蛋白功能障碍有关。第三种 HAE 占少数病例，与 C1-INH 蛋白的正常数量和功能有关。本报告中介绍的病例是一名 15 岁女孩，从 14 岁开始就有自发性血管性水肿发作的病史。发作频率最初为每两个月一次，但随后在使用一些治疗卵巢囊肿的激素药物后增加到每两周一次。每次发作持续约 10 天，其间没有任何症状。补体研究包括 C4、C1q 和 C1-INH 蛋白，无论是定量还是定性，均报告正常。基因评估显示与因子 XII 相关的基因第 9 外显子发生突变，因此确诊为 3 型 HAE。这是一种罕见类型的血管性水肿，C1-INH 蛋白数量和功能正常，主要见于女性在雌激素失衡增加期间，如妊娠、哺乳期和更年期，因此对激素治疗策略（如使用含孕激素的药物）有反应。
