Gompels M M, Lock R J, Unsworth D J, Johnston S L, Archer C B, Davies S V
Department of Immunology and Immunogenetics, Southmead Hospital, Westbury-on-Trym, Bristol, BS10 5NB, UK.
Br J Dermatol. 2003 Apr;148(4):719-23. doi: 10.1046/j.1365-2133.2003.05231.x.
Hereditary angio-oedema is a rare, life-threatening, autosomal dominant condition caused by deficiency (type 1) or dysfunction (type 2) of complement C1 inhibitor. Serological assays to measure C1 inhibitor concentration and function are widely available. However, expert interpretation may not be.
To review all cases within three NHS Trusts with a putative diagnosis of hereditary angio-oedema.
Review of laboratory results and clinical notes of 44 cases of presumed hereditary angio-oedema.
Audit revealed that 11 of 42 (26%) cases had been incorrectly considered to have a diagnosis of hereditary angio-oedema. Two of 44 had insufficient data to assess. All 11 had low functional C1 inhibitor recorded at presentation.
available in these 11 cases at the time of diagnosis showed a normal or borderline C4 level (>or= 50% of mean normal, in contrast to hereditary angio-oedema, where C4 was less than 40% of mean normal) indicating that the low C1 inhibitor levels were a result of sample decay. Cases incorrectly diagnosed were predominantly female and had a mean age at presentation of 40 years (compared with 22 years for type 1 hereditary angio-oedema). Six of the 11 cases were offered C1 inhibitor concentrate (pooled plasma product) as treatment.
We recommend that all suspected cases of hereditary angio-oedema are reviewed, that specialist advice is sought before making the diagnosis and that the diagnosis is only made after initial abnormal serology is confirmed on a second sample.
遗传性血管性水肿是一种罕见的、危及生命的常染色体显性遗传病，由补体C1抑制剂缺乏（1型）或功能障碍（2型）引起。测量C1抑制剂浓度和功能的血清学检测方法广泛可用。然而，专家解读可能并不容易获得。
回顾三个国民保健服务信托基金中所有疑似遗传性血管性水肿的病例。
回顾44例疑似遗传性血管性水肿患者的实验室检查结果和临床记录。
审核发现，42例中有11例（26%）被错误地认为患有遗传性血管性水肿。44例中有2例数据不足无法评估。所有11例在就诊时记录的功能性C1抑制剂水平均较低。
这11例患者诊断时的情况显示C4水平正常或处于临界值（>或=正常均值的50%，与遗传性血管性水肿不同，后者C4低于正常均值的40%），表明低C1抑制剂水平是样本降解的结果。被错误诊断的病例主要为女性，就诊时的平均年龄为40岁（1型遗传性血管性水肿为22岁）。11例中有6例接受了C1抑制剂浓缩物（混合血浆制品）治疗。
我们建议对所有疑似遗传性血管性水肿的病例进行复查，在做出诊断前寻求专家建议，并且只有在第二个样本确认初始血清学异常后才能做出诊断。
