Abstract：
BACKGROUND: Anti-neutrophil cytoplasmic antibody (ANCA) is a type of autoantibodies associated with vasculitis. ANCA positivity is commonly observed in interstitial lung disease (ILD) patients. 7%-10% of ANCA-positive ILD patients don\'t present any symptoms of systemic vasculitis and are termed ANCA-positive idiopathic interstitial pneumonia (ANCA-IIP). Some researchers propose that ANCA-IIP should be categorized as interstitial pneumonia with autoimmune features (IPAF), although the official ATS/ERS statements exclude ANCA-IIP from this classification. Whether ANCA-IIP should be categorized into the entity of IPAF is still debatable.
METHODS: Patients diagnosed with ANCA-IIP and those with IPAF were analyzed in a retrospective study of ILD. The clinical outcomes were determined through pulmonary function tests (PFTs) after a one-year follow-up, as well as assessing all-cause mortality.
RESULTS: 27 patients with ANCA-IIP and 143 patients with IPAF were analyzed from a cohort of 995 patients with ILD. Patients in the ANCA-IIP group had an older age and a high proportion of males compared to those in the IPAF group. PFT results at baseline were similar between the two groups, except for a better FEV1% in the ANCA-IIP group. Glucocorticoid and immunosuppressive therapy improved pulmonary function in patients with IPAF, but it continued to deteriorate after one year of treatment in the ANCA-IIP group. Furthermore, the all-cause mortality rate was significantly higher in the ANCA-IIP group than in the IPAF group (22.2% vs. 6.3%, P = 0.017).
CONCLUSIONS: The responses to glucocorticoid and immunosuppressive therapy differ between the ANCA-IIP and IPAF groups, leading to divergent prognoses. Therefore, it is inappropriate to classify ANCA-IIP as part of IPAF.
METHODS: Patients diagnosed with ANCA-IIP and those with IPAF were analyzed in a retrospective study of ILD. The clinical outcomes were determined through pulmonary function tests (PFTs) after a one-year follow-up, as well as assessing all-cause mortality.
RESULTS: 27 patients with ANCA-IIP and 143 patients with IPAF were analyzed from a cohort of 995 patients with ILD. Patients in the ANCA-IIP group had an older age and a high proportion of males compared to those in the IPAF group. PFT results at baseline were similar between the two groups, except for a better FEV1% in the ANCA-IIP group. Glucocorticoid and immunosuppressive therapy improved pulmonary function in patients with IPAF, but it continued to deteriorate after one year of treatment in the ANCA-IIP group. Furthermore, the all-cause mortality rate was significantly higher in the ANCA-IIP group than in the IPAF group (22.2% vs. 6.3%, P = 0.017).
CONCLUSIONS: The responses to glucocorticoid and immunosuppressive therapy differ between the ANCA-IIP and IPAF groups, leading to divergent prognoses. Therefore, it is inappropriate to classify ANCA-IIP as part of IPAF.
摘要：
背景：抗中性粒细胞胞浆抗体（ANCA）是一种与血管炎相关的自身抗体。通常在间质性肺病(ILD)患者中观察到ANCA阳性。7％-10％的ANCA阳性ILD患者没有任何系统性血管炎症状，被称为ANCA阳性特发性间质性肺炎（ANCA-IIP）。一些研究人员建议ANCA-IIP应归类为具有自身免疫特征的间质性肺炎（IPAF）。尽管官方的ATS/ERS声明将ANCA-IIP排除在此分类之外。ANCA-IIP是否应归类为IPAF实体仍有争议。
方法：在一项ILD的回顾性研究中分析了诊断为ANCA-IIP和IPAF的患者。随访一年后通过肺功能测试（PFTs）确定临床结果，以及评估全因死亡率。
结果：从995例ILD患者中分析了27例ANCA-IIP患者和143例IPAF患者。与IPAF组相比，ANCA-IIP组的患者年龄更大，男性比例高。两组基线时的PFT结果相似，除了在ANCA-IIP组中更好的FEV1%。糖皮质激素和免疫抑制治疗可改善IPAF患者的肺功能，但ANCA-IIP组治疗1年后继续恶化.此外，ANCA-IIP组的全因死亡率明显高于IPAF组(22.2%vs.6.3%,P=0.017)。
结论：ANCA-IIP组和IPAF组对糖皮质激素和免疫抑制治疗的反应不同，导致不同的预后。因此,将ANCA-IIP归类为IPAF的一部分是不合适的。
方法：在一项ILD的回顾性研究中分析了诊断为ANCA-IIP和IPAF的患者。随访一年后通过肺功能测试（PFTs）确定临床结果，以及评估全因死亡率。
结果：从995例ILD患者中分析了27例ANCA-IIP患者和143例IPAF患者。与IPAF组相比，ANCA-IIP组的患者年龄更大，男性比例高。两组基线时的PFT结果相似，除了在ANCA-IIP组中更好的FEV1%。糖皮质激素和免疫抑制治疗可改善IPAF患者的肺功能，但ANCA-IIP组治疗1年后继续恶化.此外，ANCA-IIP组的全因死亡率明显高于IPAF组(22.2%vs.6.3%,P=0.017)。
结论：ANCA-IIP组和IPAF组对糖皮质激素和免疫抑制治疗的反应不同，导致不同的预后。因此,将ANCA-IIP归类为IPAF的一部分是不合适的。
