Iannone Claudia, Pellico Maria Rosa, Caminati Antonella, Zompatori Maurizio, Tescaro Lisa, Luisi Francesca, Elia Davide, Mirenda Maria Rosa, Colleoni Matteo, Cassandro Roberto, Harari Sergio, Caporali Roberto Felice
ASST G. Pini-CTO. UOC Clinica Reumatologica, Milan, Italy.
Department of Clinical Sciences and Community Health, University of Milan, Milan, Italy.
Eur J Clin Invest. 2025 Jul;55(7):e70025. doi: 10.1111/eci.70025. Epub 2025 Mar 20.
Anti-neutrophil cytoplasmic antibodies (ANCA), a hallmark of systemic vasculitis (SV), have been reported in patients with idiopathic interstitial pneumonia (IIP). However, the clinical significance of ANCA in IIP remains unclear.
We retrospectively studied 101 IP patients diagnosed by pneumologists as idiopathic interstitial pneumonia (IIP,64) and IP with autoimmune features (IPAF,37). ANCA, anti-myeloperoxidase and anti-proteinase-3 were tested by immunofluorescence and ELISA. Chest HRCT patterns, pulmonary function tests (PFTs) and the evolution to SV during a 12-month follow-up were assessed. Multivariable regression analysis was performed to assess the association of baseline covariates with SV. The proximity of patients with close characteristics was investigated by cluster analysis.
Twenty-one patients (20.8%) were ANCA+, similarly distributed between IPAF and IIP. ANCA+ patients were more likely to have NSIP (p = .02) and bronchiectasis (p = .02) on HRCT, less impaired 6MWD (p = .02), higher CRP (p = .02) and more arthralgias (p < .001) than ANCA- patients. During follow-up, 9 (43%) p-ANCA+ patients, but no ANCA- patients, developed SV (p = .001). p-ANCA+ IP had 26.3 OR (95% CI 3.20-36.8) to evolve to SV within 12 months (p < .0001). Cluster analysis identified one group of 25 patients with significantly higher baseline NSIP (88%), p-ANCA+ (48%), arthralgias (32%), and SV (24%) at 12 months. Nevertheless, 12 p-ANCA+ IP patients never developed SV.
ANCA+ IP patients had a high risk of developing SV and need close monitoring and prompt immunotherapy. ANCA+ IP patients not evolving to SV had a diagnosis of IIP or IPAF. These patients need longer observational studies to investigate if they represent a distinct ILD entity.
抗中性粒细胞胞浆抗体（ANCA）是系统性血管炎（SV）的一个标志，在特发性间质性肺炎（IIP）患者中已有报道。然而，ANCA在IIP中的临床意义仍不清楚。
我们回顾性研究了101例由肺科医生诊断为特发性间质性肺炎（IIP，64例）和具有自身免疫特征的间质性肺炎（IPAF，37例）的患者。通过免疫荧光和酶联免疫吸附测定法检测ANCA、抗髓过氧化物酶和抗蛋白酶3。评估胸部高分辨率CT（HRCT）模式、肺功能测试（PFT）以及12个月随访期间向SV的病情进展。进行多变量回归分析以评估基线协变量与SV的关联。通过聚类分析研究具有相似特征患者的相近性。
21例患者（20.8%）ANCA呈阳性，在IPAF和IIP之间分布相似。与ANCA阴性患者相比，ANCA阳性患者在HRCT上更易出现非特异性间质性肺炎（NSIP）（p = 0.02）和支气管扩张（p = 0.02），6分钟步行距离（6MWD）受损较轻（p = 0.02），C反应蛋白（CRP）水平较高（p = 0.02），关节痛更多（p < 0.001）。在随访期间，9例（43%）核周型ANCA（p-ANCA）阳性患者发生了SV，但ANCA阴性患者均未发生（p = 0.001）。p-ANCA阳性的间质性肺炎患者在12个月内发展为SV的比值比（OR）为26.3（95%置信区间3.20 - 36.8）（p < 0.0001）。聚类分析确定了一组25例患者，其基线NSIP显著更高（88%）、p-ANCA阳性（48%）、关节痛（32%），且在12个月时发生SV的比例为24%。然而，12例p-ANCA阳性的间质性肺炎患者从未发生SV。
ANCA阳性的间质性肺炎患者发生SV的风险较高，需要密切监测并及时进行免疫治疗。未发展为SV的ANCA阳性间质性肺炎患者被诊断为IIP或IPAF。这些患者需要更长时间的观察性研究，以调查他们是否代表一种独特的间质性肺疾病（ILD）实体。
