Rheumatology Unit, 1st Department of Propaedeutic Internal Medicine, Joint Academic Rheumatology Program, Medical School, University of Athens, Greece.
Department of Internal Medicine, Rheumatology and Immunology, Vasculitis-Centre Tübingen-Kirchheim, Medius Klinik Kirchheim, University of Tübingen, Kirchheim-Teck, Germany.
Clin Exp Rheumatol. 2021 Mar-Apr;39 Suppl 129(2):83-87. doi: 10.55563/clinexprheumatol/08k9af. Epub 2020 Nov 5.
To evaluate the autoantibody profile in eosinophilic granulomatosis and polyangiitis (EGPA) patients.
33 EGPA patients were tested for anti-neutrophil cytoplasmic antibodies (ANCA), antinuclear antibodies (ANA), rheumatoid factor (RF), anti-alpha-enolase antibodies, and anti-eosinophil peroxidase (EPO) antibodies. Granulomatosis with polyangiitis (GPA), microscopic polyangiitis (MPA), hypereosinophilic syndrome (HES), rheumatoid arthritis (RA), primary biliary cirrhosis (PBC) patients and healthy subjects were tested as a control group.
Anti-alpha-enolase antibodies were positive in 82% of EGPA patients at high titers. Although a high sensitivity was shown for an anti-alpha-enolase antibody titer above 1/100 (82%), the specificity for EGPA remained low (44%) (AUC=0.653, p=0.008). Anti-alpha-enolase antibodies predominated in males with EGPA (p=0.048) and were associated with skin involvement (p=0.040). Most of the EGPA patients positive for anti-alpha enolase antibodies (20 out of 27) had a negative indirect immunofluorescence test (IFT) for ANCA. ANCA were positive in 8 EGPA patients (24%) with a perinuclear pattern in all but one patient. The ANCA-target antigen was myeloperoxidase (MPO) and/or alpha-enolase. A usually fine-speckled ANA pattern was observed in 42% of the EGPA patients. RF was positive in 1 (6%) of the 18 EGPA patients tested. There was no association between the presence and levels of autoantibodies and EGPA disease activity. None of the patients and controls was positive for anti-EPO antibodies.
Alpha-enolase may be a target of autoimmunity in EGPA patients and shows usually negative ANCA IFT results.
评估嗜酸性肉芽肿性多血管炎（EGPA）患者的自身抗体谱。
检测 33 例 EGPA 患者的抗中性粒细胞胞浆抗体（ANCA）、抗核抗体（ANA）、类风湿因子（RF）、抗α-烯醇化酶抗体和抗嗜酸性过氧化物酶（EPO）抗体。将肉芽肿性多血管炎（GPA）、显微镜下多血管炎（MPA）、嗜酸性粒细胞增多综合征（HES）、类风湿关节炎（RA）、原发性胆汁性肝硬化（PBC）患者和健康对照作为对照组进行检测。
82%的 EGPA 患者抗α-烯醇化酶抗体呈高滴度阳性。尽管抗α-烯醇化酶抗体滴度>1/100 时具有较高的敏感性（82%），但对 EGPA 的特异性仍较低（44%）（AUC=0.653，p=0.008）。抗α-烯醇化酶抗体在 EGPA 男性中更为常见（p=0.048），且与皮肤受累相关（p=0.040）。27 例抗α-烯醇化酶抗体阳性的 EGPA 患者中，有 20 例间接免疫荧光试验（IFT）抗中性粒细胞胞浆抗体阴性。8 例 EGPA 患者（24%）的 ANCA 阳性，除 1 例外均为核周型。ANCA 的靶抗原为髓过氧化物酶（MPO）和/或α-烯醇化酶。42%的 EGPA 患者通常出现细斑点状 ANA 模式。18 例 EGPA 患者中有 1 例（6%）RF 阳性。自身抗体的存在和水平与 EGPA 疾病活动无相关性。无患者和对照者抗 EPO 抗体阳性。
α-烯醇化酶可能是 EGPA 患者自身免疫的靶标，且通常抗中性粒细胞胞浆抗体 IFT 结果阴性。
