Csernok Elena
Department of Internal Medicine, Rheumatology and Immunology, Vasculitis-Center Tübingen-Kirchheim, Medius Klinik Kirchheim, University of Tübingen, Kirchheim-Teck, Germany.
Mediterr J Rheumatol. 2018 Mar 19;29(1):17-20. doi: 10.31138/mjr.29.1.17. eCollection 2018 Mar.
Anti-neutrophil cytoplasmic antibodies (ANCA) play a central role in the diagnosis and pathogenesis of patients with ANCA-associated vasculitis. ANCA-associated vasculitis is a rare disease characterized by necrotizing inflammation of small/medium-sized blood vessels with and without granuloma in different organs. The main syndromes are granulomatosis with polyangiitis, microscopic polyangiitis, and eosinophilic GPA. ANCA in these diseases are almost always directed against proteinase 3 and myeloperoxidase. Most laboratories worldwide use as standard the indirect immunofluorescence technique to screen for ANCA and then confirm positive IFT results with antigen specific immunoassyas for PR3- and MPO-ANCA. New guidelines for ANCA testing have been developed based on a recent European multicentre study, and according to the revised 2017 international consensus recommendations, testing for ANCA in small vessel vasculitis can be done by PR3- and MPO-ANCA immunoassays, without the categorical need for IIF. The new testing strategy for ANCA in vasculitis directly identifies the ANCA target antigen and has a particular value for the AAV sub-classification. Recent studies have shown that AAV can be classified based on ANCA serotype. ANCA presence and the antigen specificity also may have important value as a prognostic factor and may serve as a guide for immunosuppressive therapy. The clinical utility of ANCA depends on the type of assay performed and the appropiate ordering of testing the right clinical setting. Accurate identification of all patients with AAV and the avoidance of misdiagnosis can be achieved using a "gating policy" based on clinical information given to the laboratory at the time of request.
抗中性粒细胞胞浆抗体（ANCA）在ANCA相关性血管炎患者的诊断和发病机制中起核心作用。ANCA相关性血管炎是一种罕见疾病，其特征为不同器官中小/中型血管的坏死性炎症，伴有或不伴有肉芽肿形成。主要综合征包括肉芽肿性多血管炎、显微镜下多血管炎和嗜酸性肉芽肿性多血管炎。这些疾病中的ANCA几乎总是针对蛋白酶3和髓过氧化物酶。全球大多数实验室使用间接免疫荧光技术作为标准来筛查ANCA，然后通过针对PR3-ANCA和MPO-ANCA的抗原特异性免疫测定来确认阳性免疫荧光试验结果。基于最近的一项欧洲多中心研究制定了ANCA检测的新指南，根据2017年修订的国际共识建议，小血管炎中ANCA的检测可通过PR3-ANCA和MPO-ANCA免疫测定进行，并非绝对需要间接免疫荧光法。血管炎中ANCA的新检测策略直接识别ANCA靶抗原，对ANCA相关性血管炎的亚分类具有特殊价值。最近的研究表明，ANCA相关性血管炎可根据ANCA血清型进行分类。ANCA的存在及其抗原特异性作为预后因素也可能具有重要价值，并可作为免疫抑制治疗的指导。ANCA的临床效用取决于所进行的检测类型以及在正确临床环境中进行检测的适当顺序。使用基于请求时提供给实验室的临床信息的“门控策略”，可以准确识别所有ANCA相关性血管炎患者并避免误诊。
