Prevalence and Clinical Significance of Antineutrophil Cytoplasmic Antibodies in North American Patients With Idiopathic Pulmonary Fibrosis

Antineutrophil cytoplasmic antibody is an independent risk factor in rheumatoid arthritis-associated interstitial lung disease

OBJECTIVES

This study aimed to investigate the clinical relevance of antineutrophil cytoplasmic antibody (ANCA) in patients with rheumatoid arthritis-associated interstitial lung disease (RA-ILD).

METHODS

Detailed clinical records of rheumatoid arthritis (RA) patients who underwent ANCA screening tests were collected. ANCA measurements were determined by indirect immunofluorescence assay (IIF) and enzyme-linked immunosorbent assay (ELISA). Clinical characteristics were compared between ANCA-positive and ANCA-negative groups, and multivariable logistic models were used to evaluate the independent association of ANCA with ILD in RA patients.

RESULTS

The prevalence of ANCA by IIF was significantly higher in RA-ILD patients compared to those with RA without ILD (31.7 % vs. 19.5 %, p < 0.001). RA-ILD patients positive for ANCA exhibited elevated levels of inflammatory markers and greater disease activity, and showed more severe impairment of lung function compared to ANCA-negative RA-ILD patients. Multivariable logistic regression analysis revealed an independent association of ANCA, especially pANCA, with RA-ILD. ANCA specificities for BPI, elastase, and cathepsin-G were found in 15.6 % of RA-ILD patients; the specificities for most others remain unknown.

CONCLUSIONS

The findings suggest a potential role for ANCA/pANCA in stratifying the risk of RA and provide supplementary information to the existing clinically available assays. This additional information may be valuable in identifying RA patients who require further investigations for RA-ILD, such as high-resolution computed tomography (HRCT). These results emphasize the potential clinical relevance of ANCA in the context of RA-ILD.

Presentation and progression of MPO-ANCA interstitial lung disease

The association between MPO-ANCA-associated vasculitis (AAV) and interstitial lung disease (ILD) has been well established. Pulmonary fibrosis may coexist with, follow, or even precede the diagnosis of AAV, and its presence adversely affects the prognosis. The optimal approach to investigating ANCA in patients with ILD remains a subject of ongoing debate. Here we aim to describe presentation and progression of MPO-ANCA ILD. We conducted a retrospective evaluation of a cohort of individuals diagnosed with MPO-ANCA ILD, with or without accompanying renal impairment, at the Immunology and Cell Therapy Unit, Careggi University Hospital, Florence, Italy, between June 2016 and June 2022. Clinical records, imaging studies, pathologic examinations, and laboratory test results were collected. Among the 14 patients identified with MPO-ANCA ILD, we observed a significant association between MPO-ANCA titers assessed at the time of ILD diagnosis and renal involvement. Renal impairment in these cases often manifested as subclinical or slowly progressive kidney damage. Interestingly, complement C3 deposits were consistently found in all renal biopsy specimens, thereby suggesting the potential for novel therapeutic targets in managing renal complications associated with MPO-ANCA ILD. The presentation of MPO-ANCA vasculitis as ILD can be the first and only clinical manifestation. MPO-ANCA levels at ILD diagnosis could warn on the progression to renal involvement in patients with MPO-ANCA ILD, hence caution is needed because renal disease can be subclinical or smoldering.

Progression to ANCA-associated vasculitis in patients with idiopathic interstitial pneumonia and positive ANCA

OBJECTIVE

This study explored the development of antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) and its risk factors in patients with idiopathic interstitial pneumonia (IIP) and positive ANCA results.

METHODS

Data of patients diagnosed with IIP with positive ANCA results at a single tertiary center in South Korea were retrospectively reviewed from January 2013 to August 2023. Cox regression analysis was performed to identify variables associated with AAV occurrence following IIP diagnosis. Kaplan-Meier curves were employed to investigate the relationship between autoantibodies and the occurrence of AAV.

RESULTS

In a cohort of 154 IIP-diagnosed patients with positive ANCA results but without AAV, 10.4 % of them eventually developed AAV. The AAV and non-AAV groups did not significantly differ by sex, age, smoking status, urinalysis, or chest computed tomography findings. All the patients who subsequently developed AAV were anti-myeloperoxidase (MPO) positive, while 48.8 % of the non-AAV patients were anti-MPO positive (P < 0.001). Rheumatoid factor (RF) positivity differed significantly (62.5 % vs. 29.2 %, P = 0.007) between the AAV and non-AAV groups. Multivariate Cox regression and Kaplan-Meier analyses revealed RF (HR 4.02; P = 0.004) and anti-MPO (HR 38.10; P < 0.001) positivity as risk factors associated with AAV occurrence.

CONCLUSION

Approximately 10 % of ANCA-positive IIP patients developed AAV after an IIP diagnosis. Anti-MPO or co-occurring positive RF poses a significant risk for subsequent AAV occurrence. This emphasizes the importance of careful monitoring in patients with high-risk antibody profiles, even if the complete features of AAV are not present at IIP diagnosis.

Pathogenesis of Pulmonary Manifestations in ANCA-Associated Vasculitis and Goodpasture Syndrome

Pulmonary manifestations of vasculitis are associated with significant morbidity and mortality in affected individuals. They result from a complex interplay between immune dysregulation, which leads to vascular inflammation and tissue damage. This review explored the underlying pathogenesis of pulmonary involvement in vasculitis, encompassing various forms such as granulomatosis with polyangiitis (GPA), microscopic polyangiitis (MPA), eosinophilic granulomatosis with polyangiitis (EGPA), and anti-GBM disease. Mechanisms involving ANCA and anti-GBM autoantibodies, neutrophil activation, and neutrophil extracellular trap (NETs) formation are discussed, along with the role of the complement system in inducing pulmonary injury. Furthermore, the impact of genetic predisposition and environmental factors on disease susceptibility and severity was considered, and the current treatment options were presented. Understanding the mechanisms involved in the pathogenesis of pulmonary vasculitis is crucial for developing targeted therapies and improving clinical outcomes in affected individuals.

Neutrophil extracellular traps linked to idiopathic pulmonary fibrosis severity and survival

Background

Idiopathic pulmonary fibrosis (IPF) leads to progressive loss of lung function and mortality. Understanding mechanisms and markers of lung injury in IPF is paramount to improving outcomes for these patients. Despite the lack of systemic involvement in IPF, many analyses focus on identifying circulating prognostic markers. Using a proteomic discovery method followed by ELISA validation in multiple IPF lung compartments and cohorts we explored novel markers of IPF survival.

Methods

In our discovery analysis, agnostic label-free quantitative proteomics differentiated lung tissue protein expression based on survival trajectory (n=10). Following selection of the candidate pathway (neutrophil extracellular trap (NET) formation), we subsequently validated the presence of NETs in the IPF lung microenvironment using fully quantitative assays of known NET remnants in separate IPF cohorts (n=156 and n=52) with bronchoalveolar lavage fluid. We then assessed the correlation of these markers with baseline pulmonary function and survival.

Results

Discovery lung tissue proteomics identified NET formation as significantly associated with poor IPF survival. Using fully quantitative confirmatory tests for reproducibility we confirmed the presence of NET markers in IPF BALF and found significant correlations with worse pulmonary function in both cohorts (p<0.03 and p = 0.04 respectively). In the survival cohort, higher levels of NET markers predicted worse survival after adjusting for gender, age, and baseline physiologic severity (hazard ratio range: 1.79-2.19).

Conclusions

NET markers were associated with disease severity and worse survival in IPF. These findings suggest NET formation contributes to lung injury and decreased survival in IPF and may represent a potential therapeutic target.

Myeloperoxidase-specific antineutrophil cytoplasmic antibody-associated vasculitis

Myeloperoxidase (MPO)-specific antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (MPO-ANCA-associated vasculitis) is one of two major ANCA-associated vasculitis variants characterised by systemic necrotising vasculitis with few or no immune deposits. MPO-ANCA-associated vasculitis predominantly affects small blood vessels and, in contrast to its counterpart proteinase 3-ANCA-associated vasculitis, is generally not associated with granulomatous inflammation. The kidneys and lungs are the most commonly affected organs. The pathogenesis of MPO-ANCA-associated vasculitis is characterised by loss of tolerance to the neutrophil enzyme MPO. This loss of tolerance leads to a chronic immunopathological response where neutrophils become both the target and effector of autoimmunity. MPO-ANCA drives neutrophil activation, leading in turn to tissue and organ damage. Clinical trials have improved the therapeutic approach to MPO-ANCA-associated vasculitis. However, there remains substantial unmet need regarding relapse frequency, toxicity of current treatment, and long-term morbidity. In this Series paper, we present the current state of research regarding pathogenesis, diagnosis, and treatment of MPO-ANCA-associated vasculitis.

Interstitial lung diseases associated with ANCA positivity: A different disease spectrum from interstitial pneumonia with autoimmune features

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).

CONCLUSION

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.

Desquamative Interstitial Pneumonia with Progressive Pulmonary Fibrosis

A 70-year-old man who smoked was referred to our hospital because of progressive cough and dyspnea. Radiologic images showed ground-glass attenuation predominantly in the lower lung lobes. A surgical lung biopsy was performed, and a diagnosis of desquamative interstitial pneumonia (DIP) was made. The patient's symptoms improved with smoking cessation and steroid treatment, but the ground-glass attenuation did not completely resolve. At 10 years after the diagnosis, the fibrotic lesions deteriorated and treatment with nintedanib was subsequently initiated. Careful observation is needed in patients with DIP whose lung involvement does not completely improve with initial treatment.

Usual interstitial pneumopathy in a patient with hypersensitivity pneumonitis and microscopic polyangiitis. Case report

One of the most frequent diffuse interstitial lung diseases is hypersensitivity pneumonitis. It is related to exposure to diverse antigens, causing fibrosis in advanced stages, making the differential diagnosis with interstitial pulmonary fibrosis difficult as it overlaps with the usual interstitial pneumonia pattern. On the other hand, there are interstitial lung diseases associated with ANCA, such as microscopic polyangiitis, which is also related to the usual interstitial pneumonia pattern. We present the case of a 74-year-old male patient with chronic dyspnea, history of smoking and exposure to organic particles, in addition to a pattern suggestive of moderately severe restriction. The diagnosis was confirmed by histology of hypersensitivity pneumonitis by presenting granules, however, anti MPO and p-ANCA positivity was found, integrating the simultaneous diagnosis of microscopic polyangiitis. This is a case of difficult diagnosis since these pathologies have not been previously reported to coexist.

Immune-mediated lung diseases: A narrative review

The role of immunity in the pathogenesis of various pulmonary diseases, particularly interstitial lung diseases (ILDs), is being increasingly appreciated as mechanistic discoveries advance our knowledge in the field. Immune-mediated lung diseases demonstrate clinical and immunological heterogeneity and can be etiologically categorized into connective tissue disease (CTD)-associated, exposure-related, idiopathic, and other miscellaneous lung diseases including sarcoidosis, and post-lung transplant ILD. The immunopathogenesis of many of these diseases remains poorly defined and possibly involves either immune dysregulation, abnormal healing, chronic inflammation, or a combination of these, often in a background of genetic susceptibility. The heterogeneity and complex immunopathogenesis of ILDs complicate management, and thus a collaborative treatment team should work toward an individualized approach to address the unique needs of each patient. Current management of immune-mediated lung diseases is challenging; the choice of therapy is etiology-driven and includes corticosteroids, immunomodulatory drugs such as methotrexate, cyclophosphamide and mycophenolate mofetil, rituximab, or other measures such as discontinuation or avoidance of the inciting agent in exposure-related ILDs. Antifibrotic therapy is approved for some of the ILDs (e.g., idiopathic pulmonary fibrosis) and is being investigated for many others and has shown promising preliminary results. A dire need for advances in the management of immune-mediated lung disease persists in the absence of standardized management guidelines.

Interstitial Lung Disease and Anti-Neutrophil Cytoplasmic Antibody–Associated Vasculitis

Interstitial lung disease is a common complication of anti-neutrophil cytoplasmic antibody-associated vasculitis (AAV). It is seen most commonly in microscopic polyangiitis owing to the pathogenic effect of myeloperoxidase in the lung. Oxidative stress, neutrophil elastase release, and expression of inflammatory proteins by neutrophil extracellular traps result in fibroblast proliferation and differentiation and therefore fibrosis. Usually, interstitial pneumonia pattern fibrosis is common and associated with poor survival. Treatment for patients with AAV and interstitial lung disease lacks evidence, and those with vasculitis are treated with immunosuppression, whereas those with progressive fibrosis may well benefit from antifibrotic therapy.

Long-term survival, causes of death, and prognostic factors for mortality in patients with microscopic polyangiitis and those with anti-neutrophil cytoplasmic antibody-positive interstitial lung disease: A single-center retrospective study

AIM

To elucidate the clinical features, long-term survival, and prognostic factors for mortality among patients with microscopic polyangiitis (MPA), including those with anti-neutrophil cytoplasmic antibody-positive interstitial lung disease (ILD) (ANCA-ILD), which could be a subset of its variant phenotype.

METHODS

We retrospectively included 76 consecutive patients between 2006 and 2014, diagnosed with MPA according to the European Medicines Agency algorithm using the Chapel Hill Consensus Conference definitions or ANCA-ILD. ILD was classified as usual interstitial pneumonia (UIP) or nonspecific interstitial pneumonia pattern using chest computed tomography.

RESULTS

The mean (standard deviation) age of the patients (female, 68%) was 69 (12) years. The median (interquartile range) follow-up period was 68 (33-95) months. Comorbid ILD and glomerulonephritis were observed in 44 (58%) (68% UIP) and 54 (71%) patients, respectively. Comorbid ILD was associated with low survival (P = .0563). There were 17 (39%) and 5 (16%) deaths in the ILD and non-ILD groups, respectively (P = .0404). In the ILD group, 6 and 5 of the deaths were attributed to infection and ILD progression, respectively. In the non-ILD group, 1 and 2 patients expired from subsequently developed ILD and aspiration pneumonia, respectively. Age ≥ 70 years (hazard ratio = 2.78; 95% confidential interval 1.15-6.70) and UIP (3.95; 1.60-9.77) were independent risk factors for mortality.

CONCLUSION

Age ≥ 70 years and ILD with a UIP pattern were associated with high mortality, owing to susceptibility to infection and ILD progression. A more effective and less toxic treatment is required for progressive ILD.

Interstitial lung disease in ANCA-associated vasculitis: associated factors, radiographic features and mortality

OBJECTIVE

To evaluate the prevalence, clinical and radiographic features, and long-term outcomes of interstitial lung disease (ILD) in a United States-based ANCA-associated vasculitis (AAV) cohort.

METHODS

In this retrospective cohort study, we identified cases of ILD within the 2002-2019 Mass General Brigham AAV Cohort, a consecutive inception cohort of PR3- or MPO-ANCA+ AAV patients. ILD diagnosis and classification as fibrotic or non-fibrotic were confirmed by review of available chest imaging by two board-certified radiologists. Cox proportional hazard models, with age as the time scale, were used to estimate the association of AAV-ILD with all-cause mortality.

RESULTS

Of 684 patients in the MGB AAV Cohort, 91 (13%) had ILD which preceded the diagnosis of AAV by a mean of 2.2 years. AAV-ILD patients were older (67 vs 60 years, P < 0.001) than patients without ILD but the distribution of sex and race was similar. AAV-ILD patients were more often MPO-ANCA+ (93% vs 65%, P < 0.001); among MPO-ANCA+ patients (n = 470), 85 (18%) had ILD. The majority of ILD was fibrotic (76%) and UIP was the most common ILD pattern (42%). The baseline forced vital capacity (FVC) % predicted among ILD patients was 81 ± 20%. Fibrotic AAV-ILD was associated with a 58% higher risk of death (aHR 1.58, 95% CI 1.06, 2.37) compared with AAV patients without ILD.

CONCLUSION

ILD is a frequent complication of AAV, especially MPO-ANCA+ AAV, often preceding recognition of AAV. Fibrotic AAV-ILD is associated with a higher risk of death than AAV without ILD.

Fine-tuning characterization of patients with interstitial pneumonia and an underlying autoimmune disease in real-world practice: We get closer with Nailfold videocapillaroscopy

Objectives

To assess performance of interstitial pneumonia (IP) with autoimmune features (IPAF) criteria in clinical practice and describe the utility of additional workup in identifying patients with underlying connective tissue diseases (CTD).

Methods

We set a retrospective study of our patients with autoimmune IP, who were allocated to CTD-IP, IPAF or undifferentiated autoimmune IP (uAIP) subgroups according to the updated classification criteria. Presence of the process-related variables comprising IPAF defining domains was scrutinized in all patients, and, when available, the results of nailfold videocapillaroscopy (NVC) were recorded.

Results

Thirty nine out of 118 patients, accounting for 71% of former undifferentiated cases, fulfilled IPAF criteria. Arthritis and Raynaud's phenomenon were prevalent in this subgroup. While systemic sclerosis-specific autoantibodies were restricted to CTD-IP patients, anti-tRNA synthetase antibodies were also present in IPAF. In contrast, rheumatoid factor, anti-Ro antibodies and ANA nucleolar patterns could be found in all subgroups. Usual interstitial pneumonia (UIP) / possible UIP were the most frequently observed radiographic patterns Therefore, the presence of thoracic multicompartimental findings as also performance of open lung biopsies were useful in characterizing as IPAF those UIP cases lacking a clinical domain. Interestingly, we could observe NVC abnormalities in 54% of IPAF and 36% of uAIP tested patients, even though many of them did not report Raynaud's phenomenon.

Conclusion

Besides application of IPAF criteria, distribution of IPAF defining variables along with NVC exams help identify more homogeneous phenotypic subgroups of autoimmune IP of potential relevance beyond clinical diagnosis.

A Precise Method to Detect Post-COVID-19 Pulmonary Fibrosis Through Extreme Gradient Boosting

The association of pulmonary fibrosis with COVID-19 patients has now been adequately acknowledged and caused a significant number of mortalities around the world. As automatic disease detection has now become a crucial assistant to clinicians to obtain fast and precise results, this study proposes an architecture based on an ensemble machine learning approach to detect COVID-19-associated pulmonary fibrosis. The paper discusses Extreme Gradient Boosting (XGBoost) and its tuned hyper-parameters to optimize the performance for the prediction of severe COVID-19 patients who developed pulmonary fibrosis after 90 days of hospital discharge. A dataset comprising Electronic Health Record (EHR) and corresponding High-resolution computed tomography (HRCT) images of chest of 1175 COVID-19 patients has been considered, which involves 725 pulmonary fibrosis cases and 450 normal lung cases. The experimental results achieved an accuracy of 98%, precision of 99% and sensitivity of 99%. The proposed model is the first in literature to help clinicians in keeping a record of severe COVID-19 cases for analyzing the risk of pulmonary fibrosis through EHRs and HRCT scans, leading to less chance of life-threatening conditions.

Clinical significance of acute exacerbation in interstitial lung disease with antineutrophil cytoplasmic antibody: an indicator of poor prognosis

BACKGROUND

The association between interstitial lung disease (ILD) and antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) has been increasingly recognized in recent years. The clinical features and prognostic differences between AAV-associated ILD and isolated ANCA-positive idiopathic interstitial pneumonias (IIPs) remain unclear. The purpose of this study was to determine the clinical significance and prognosis of ANCA-positive ILD to further guide clinical management.

METHODS

This study retrospectively reviewed the data of 379 ILD patients with available ANCA results and ultimately analysed 49 ANCA-positive patients. AAV diagnosis was based on the 2012 revised Chapel Hill Consensus Conference (CHCC) criteria, and 33 of 49 patients were diagnosed with microscopic polyangiitis (MPA). The baseline clinical information and laboratory parameters were collected and analysed at each patient's initial diagnosis.

RESULTS

Among 49 ANCA-positive ILD patients, the high-resolution computed tomography (HRCT) pattern was mainly usual interstitial pneumonia (UIP) (59.18%), followed by nonspecific interstitial pneumonia (NSIP) (26.53%). The C-reactive protein (CRP) level (43.89± 40.61 versus 18.74± 20.05, p = 0.028) and erythrocyte sedimentation rate (ESR) (71.97± 42.73 versus 40.69± 28.46, p = 0.011) were significantly higher in the MPA-ILD group than in the ANCA-IIP group. Haemoglobin (113.09 ± 24.47 versus 132.19± 13.34, p = 0.006) and albumin (32.95± 5.84 versus 36.52± 3.94, p = 0.032) levels were significantly lower. Survival was shorter among MPA-ILD patients than among ANCA-IIP patients [hazard ratio (HR) 3.38, 95% confidence interval (CI) 1.32-8.67, p = 0.040]. In the multivariable Cox analysis, a diagnosis of MPA (HR 3.91, 95% CI 1.07-14.08, p = 0.038) and acute exacerbation (AE) of ILD (HR 9.43, 95% CI 2.89-30.30, p < 0.001) were significantly independently associated with shorter survival in ANCA-positive ILD patients, and the NSIP pattern (HR 0.07, 95% CI 0.01-0.41, p = 0.003) was independently associated with prolonged survival.

CONCLUSION

ANCA-ILD patients mostly have myeloperoxidase (MPO)-ANCA positivity and an MPA diagnosis. Survival was shorter among MPA-ILD patients than among ANCA-IIP patients. Respiratory failure and AE were associated with poorer prognosis. Early antifibrotic treatment may be a reasonable treatment option in fibrotic ILD patients with ANCA positivity.

Interstitial Lung Disease in ANCA-Associated Vasculitis: Pathogenic Considerations and Impact for Patients' Outcomes

PURPOSE OF REVIEW

This review provides an update on recent advances in the diagnosis, pathogenesis, clinical presentation, histopathological findings, and treatment approaches for antineutrophil cytoplasmic antibody (ANCA) vasculitis-associated interstitial lung disease (AAV-ILD) with a focus on literature published in the last 3 years.

RECENT FINDINGS

Although there is no validated definition of AAV-ILD, which contributes to some of the heterogeneity seen in study results, there has been an increasing number of publications in recent years on this topic. Most patients with AAV-ILD have MPO-ANCA vasculitis, and this association appears to reduce their 5-year-survival to 60-66% (Sun et al. BMC Pulm Med 21(1), 2021, Maillet et al. J Autoimmun 106, 2020). Median age of diagnosis ranges from mid-60 s to mid-70 s (Ando et al. Respir Med 107(4), 2013), Kagiyama et al. BMJ Open Respir Res 2(1):1-9, 2015, Hozumi et al. Lung 194(2):235-42, 2016, Liu et al. Chest 156(4):715-23, 2019, Maillet et al. J Autoimmun 106, 2020, Wurmann et al. Sarcoidosis Vasc Diffuse Lung Dis 37(1):37-42, 2020, Watanabe et al. BMC Pulm Med 19(1), 2019). Computed tomography (CT) chest imaging for patients with AAV-ILD often shows a usual interstitial pneumonia (UIP) or nonspecific interstitial pneumonia (NSIP) pattern (12-58% and 13-61%, respectively) (Sun et al. BMC Pulm Med 21(1), 2021, Maillet et al. J Autoimmun 106, 2020, Wurmann et al. Sarcoidosis Vasc Diffuse Lung Dis 37(1):37-42, 2020, Watanabe et al. BMC Pulm Med 19(1), 2019, Baqir at al. Sarcoidosis Vasc Diffuse Lung Dis Off J WASOG 36(3):195-201, 2019). Additionally, lung biopsies typically do not demonstrate active inflammation, or capillaritis, questioning whether these patients should be treated with either immunotherapy or anti-fibrotic therapy, or both (Hozumi et al. Lung 194(2):235-42, 2016, Liu et al. Chest 156(4):715-23, 2019, Kitching at al. Nat Rev Dis Prim 6(1):71, 2020, Tanaka et al. Respir Med 106(12):1765-70, 2012). Besides immunosuppressive treatments, recent advances in anti-fibrotic therapy may offer patients with progressive AAV-ILD an alternative and/or more effective and individualized treatment option.

Anti-Inflammatory and/or Anti-Fibrotic Treatment of MPO-ANCA-Positive Interstitial Lung Disease: A Short Review

The presence of a lung lesion is common in microscopic polyangiitis (MPA), and interstitial lung disease (ILD) can lead to a poor prognosis. Although myeloperoxidase antineutrophil cytoplasmic antibodies (MPO-ANCA) are often present in patients with MPA, patients with ILD and MPO-ANCA positivity but without other manifestations of systemic vasculitis have also been reported. Therefore, the possible association between MPO-ANCA, MPA, and idiopathic ILD remains unclear. This problematic matter has influenced the treatment strategy of MPO-ANCA-positive ILD patients without systemic vasculitis. Clinicians should undertake treatment with careful consideration of the four major causes of death in MPO-ANCA-positive ILD: acute exacerbation of ILD, progressive lung fibrosis, infectious comorbidities, and diffuse alveolar hemorrhage. Further, clinicians need to carefully judge whether inflammation or fibrosis is the dominant condition with reference to the patient’s clinical domain and radiopathological lung features. Recently, anti-fibrotic agents such as nintedanib and pirfenidone were shown to be effective in treating various etiologies associated with ILD and have thus led to the widening of treatment options. In this review, the clinical characteristics, radiopathology, prognosis, and therapeutic options in patients with MPO-ANCA-positive ILD are summarized using limited information from previous studies.

ANCA-associated vasculitis in idiopathic pulmonary fibrosis: A case report and brief review of the literature

RATIONALE

Idiopathic pulmonary fibrosis (IPF) is a progressive disease with poor prognosis. Patients with IPF represent a heterogeneous population with several described clinical phenotypes. More recently, the development of antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis in IPF patients, with an incidence higher than that in the general population, has drawn attention.

PATIENT CONCERNS

A 64-year-old woman previously diagnosed with IPF presented to the emergency department with hemoptysis and hypoxemic respiratory failure.

DIAGNOSES

High-resolution chest computed tomography revealed bilateral ground-glass opacities associated with areas of consolidation superimposed on the patient's fibrotic background pattern. Diffuse alveolar hemorrhage was confirmed by the presence of hemorrhagic bronchoalveolar lavage fluid. Hematological and biochemical investigations revealed an inflammatory syndrome, moderate anemia, and rapidly progressive glomerulonephritis. Serological analysis revealed perinuclear antineutrophil cytoplasmic antibody positivity and high levels of antimyeloperoxidase antibodies antibodies. The patient underwent kidney biopsy, which revealed necrotizing glomerulonephritis. Clinical and laboratory findings were diagnostic of microscopic polyangiitis with lung and renal involvement.

INTERVENTIONS

Cyclophosphamide in combination with methylprednisolone was administered as remission induction therapy. The maintenance therapy consisted of mycophenolate mofetil and prednisone.

OUTCOMES

The patient achieved clinical, radiological, and serological remission within six weeks of treatment.

LESSONS

The association between IPF and ANCA-associated vasculitis may represent a distinct clinical phenotype. Autoimmune testing for ANCAs should be considered part of the diagnostic work-up and follow-up of patients with IPF because of the clinical and therapeutic implications of developing vasculitis in an already vulnerable patient.

Are sputum autoantibodies more clinically relevant in idiopathic pulmonary fibrosis than serum autoantibodies?

BACKGROUND

The adaptive immune system plays a role in the pathogenesis of idiopathic pulmonary fibrosis (IPF) has been reported previously. However, the association between airway and circulating autoantibodies (AAbs) levels is unclear. The aim of this study is to investigate the link between the AAb levels in airway and circulation in stable patients with IPF.

MATERIALS AND METHODS

From June 2016 to March 2017, 21 stable IPF patients and 22 healthy volunteers were recruited. We established Luminex interacting AAbs with bead-antigen complex to detect the immunoglobulin G antibodies levels of ten autoantigens which were matched serum (Se) and sputum (Sp) samples collected from recruited subjects, including Smith (Sm), Anti-ribosomal P antibody (P0), Sjögren syndrome type A antigen (SSA), La/Sjögren syndrome type B antigen (SSB), DNA topoisomerase (Scl-70), histidyl-tRNA synthetase (Jo-1), U1 small nuclear ribonucleoprotein (U1-SnRNP), thyroid peroxidase, Proteinase 3, and Myeloperoxidase. Spearman's rank correlation matrix was applied to explore the associations of Ab profiles between Se and Sp.

RESULTS

For IPF patients, Spearman's correlation matrix showed multiple intercorrelations among Sp-AAbs and Sp-AAbs (P < 0.05), while only the levels of AAb against Sm and anti-La in Se were correlated with those Sp-AAb counterparts (P < 0.05). For healthy individuals, only anti-La in Se was associated with those Sp-AAb counterparts (P < 0.05). For IPF patients, there was a positive correlation between carbon monoxide diffusing capacity (DL_CO)% predicted and Sp-anti-P0 level (r = 0.464, P = 0.034). Forced vital capacity% predicted was positively correlated with Sp-anti-Scl-70 level (r = 0.466, P = 0.033).

CONCLUSION

Comparing to Se-AAbs, Sp-AAbs are more associated with clinical parameters in the patients with IPF. In order to better understand the role of autoimmunity in the pathogenesis of IPF, detection of Sp-AAbs for local autoimmune responses may be a good choice.

Antineutrophil cytoplasmic antibody-associated interstitial lung disease: a review

Over the past three decades, an increasing number of publications have reported the association between interstitial lung disease (ILD) and anti-neutrophil cytoplasmic antibody (ANCA) or ANCA-associated vasculitis (AAV). With this increased awareness, we have reviewed the literature to date and provide an update in this narrative review. The vast majority of cases of ILD have been shown to be in the setting of positive anti-myeloperoxidase antibody and can be present in up to 45% of patients of microscopic polyangiitis, though cases of ILD associated with proteinase 3 ANCA have rarely been reported. Pulmonary fibrosis and ANCA positivity can occur with or without systemic involvement. The pathogenetic mechanisms establishing the relationship between ANCA and the development of pulmonary fibrosis remain unclear. Histologic and radiographic features of ANCA-ILD most commonly reveal usual interstitial pneumonia or non-specific interstitial pneumonia patterns, though other atypical features such as bronchiolitis have been described. ILD in the setting of AAV has been associated with worse outcomes, and thus early identification and treatment in these patients is appropriate. We advocate that ANCA antibody testing be performed as a baseline evaluation in patients presenting with idiopathic interstitial pneumonia. Suggested treatment of ANCA-ILD includes immunosuppression and/or antifibrotic agents, though supporting data and clinical trials to substantiate use of these therapies are needed.

Myeloperoxidase and associated lung disease: Review of the latest developments

Myeloperoxidase (MPO) anti-neutrophil cytoplasmic antibodies (ANCA) are often detected in association with a variety of lung pathologies, the most common being interstitial lung disease (ILD). A growing cohort of patients are being diagnosed with MPO-ANCA in the context of ILD without ANCA-associated vasculitis. Clinically and radiologically, there is little to differentiate this cohort from MPO-ANCA-negative ILD patients; however, the pathophysiology is likely different and different treatments are likely required. We present here a brief summary of the proposed pathophysiology of MPO-ANCA-positive ILD, and a more detailed review of the latest evidence on management, including monitoring for development of ANCA-associated vasculitis, immunosuppression, anti-fibrotics, and novel agents that have yet to be trialled in human experiments.

Relationship between Renal Damage and Serum Complement C3 in Children with Anti-Neutrophil Cytoplasmic Antibody-Associated Vasculitis

BACKGROUND

Anti-neutrophil cytoplasmic antibody-associated vasculitis (AAV) disease is a well-known antibody-induced autoimmune disease. The pathogenesis of AAV has not yet been completely clarified, but may be related to heredity, infection, environmental factors, cellular immunity, etc. In recent years, complement in AAV pathogenesis has become the latest research hotspot, and the decrease of serum complement C3 is associated with poor prognosis of anti-neutrophil cytoplasmic antibody-associated glomerulonephritis. In the current study, we investigated the associations between serum complement C3 and kidney injury in AAV children.

METHODS

Twenty-four children with AAV admitted to our hospital from June 2014 to June 2019 were divided into the low C3 group and the normal C3 group. All the children have undergone renal biopsy. The clinical manifestations, laboratory tests, renal pathology, treatment, and prognosis of the 2 groups were observed. The primary end point was end-stage renal disease (ESRD).

RESULTS

It was shown that kidney injury was more obvious in patients with low C3 than in patients with normal C3 serum. The values of ESR, Scr, and UA before treatment in the low C3 group were higher than those in the normal C3 group (p < 0.01); the values of RBC, Hb, PLT, ALB, LDH, and eGFR in the normal C3 group were higher than those in the low C3 group (p < 0.01). The values of urinary protein and NAG enzyme in the low C3 group were higher than those in the normal C3 group (p < 0.01). The area of glomerular abandonment, sclerosis, segmental sclerosis, crescent, cellular crescent, cellular fibrous crescent, fibrous crescent, segmental loop necrosis, and the number of cases with acute renal tubulointerstitial lesions in the low C3 group were bigger than those in the normal C3 group (p < 0.05 and < 0.01). The number of cases with C3 deposition in the low C3 group was higher than that in the normal C3 group (p < 0.05). The number of patients receiving CRRT and PE in the low C3 group was higher than that in the normal C3 group (p < 0.05 and < 0.01). In this study, 3 children entered the stage of ESRD and 1 died in the low C3 group.

CONCLUSION

The kidney injury of AAV children with low complement C3 is serious, and the prognosis is poor. We should pay attention to the influence of decreased complement C3 on the condition and prognosis of AAV children.

Utility of anti-neutrophil cytoplasmic antibody screening in idiopathic interstitial lung disease

Background:

Interstitial lung disease (ILD) is an established manifestation of anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis. Autoimmune serologic screening is recommended by international consensus guidelines during the evaluation of idiopathic ILD, but ANCA testing only on a case-by-case basis.

Objective:

We aimed to evaluate the role of ANCA screening in patients with idiopathic ILD.

Methods:

We performed a retrospective review of patients seen between September 2015 and April 2017 in the ILD clinic at Toronto General Hospital. Patients referred with confirmed or suspected connective tissue disease were excluded. Patient demographics, symptoms, chest imaging, and pulmonary function testing was collected. We performed descriptive statistics based on the presence of ANCAs and estimated operating characteristics for ANCA screening.

Results:

In total, 360 patients with idiopathic ILD were reviewed, 159 met study inclusion criteria and 4 (2.5%) tested positive for ANCAs. Two patients (1.2%) had elevated myeloperoxidase-ANCAs (MPO-ANCA) and 2 (1.2%) had elevated proteinase-3-ANCAs (PR3-ANCA). There were no significant associations between patient demographics and ANCAs. One patient (0.6%) with PR3-ANCAs was diagnosed with vasculitis following rheumatologic evaluation. Despite negative ANCA testing, 1 patient (0.6%) was diagnosed with vasculitis following rheumatologic evaluation. The sensitivity and specificity of ANCA screening for vasculitis in patients with ILD was calculated as 50% (95% CI, 1.3%-98.7%) and 98% (95%CI, 4.4-155.5) respectively. Negative and positive likelihood ratios were 0.5 (95%CI 0.1-2.0) and 26.2 (95%CI 4.4-155.5) respectively.

Conclusion:

ANCA screening in patients with idiopathic ILD rarely yields positive results. These results support an individualized approach to ANCA testing as opposed to widespread screening.

New therapeutic strategies in lung vasculitis

PURPOSE OF REVIEW

To summarize the latest publications and provide a practical overview of treatment strategies for lung vasculitis associated with antineutrophil cytoplasmic antibodies (ANCAs).

RECENT FINDINGS

In patients with severe ANCA-associated vasculitis, plasma exchange, as adjunctive therapy to standard treatment, is not associated with improved survival or reduced risk of end-stage kidney disease. A regimen with reduced dose of glucocorticoids is equally effective to induce remission as a standard regimen. In patients without organ or life-threatening disease, mycophenolate mofetil can be used in combination with oral glucocorticoid therapy to induce remission, however, with a higher risk of relapse than when using rituximab or cyclophosphamide. For maintenance of remission, a tailored regimen of rituximab infusion was equivalent to a fixed regimen, with fewer perfusions. Belimumab, a human IgG1(Equation is included in full-text article.)monoclonal antibody against B-lymphocyte stimulator, did not decrease the relapse rate when added to azathioprine and glucocorticoids. Avacopan, a complement C5a receptor inhibitor, was effective in replacing high-dose glucocorticoids in achieving complete remission of vasculitis.

SUMMARY

Significant advances have been made in the treatment strategy to both induce remission and maintain remission in patients with ANCA-associated vasculitis. The choice should take into consideration efficacy, cost-effectiveness, safety profile, ease of use, and possibility of individual tailoring of treatment.

Interstitial Lung Disease and Anti-Myeloperoxidase Antibodies: Not a Simple Association

Anti-neutrophil cytoplasmic antibodies (ANCA), mainly anti-myeloperoxidase (MPO) antibodies, have been frequently identified in patients with idiopathic pulmonary fibrosis (IPF). However, their role remains unclear, and only 7–23% of these patients develops clinically overt vasculitis. We aimed to investigate the clinical, serological, and radiological features and prognosis of anti-MPO-positive interstitial lung disease (ILD) patients. Fifty-eight consecutive patients firstly referred for idiopathic interstitial pneumonia and showing serological positivity of anti-MPO antibodies were retrospectively enrolled. For each patient, clinical data, lung function testing, chest high-resolution computed tomography (HRCT) pattern, and survival were recorded. Thirteen patients developed a rheumatic disease during a median follow-up of 39 months. Usual interstitial pneumonia (UIP) was the most frequent ILD pattern, significantly influencing the patients’ survival. In fact, while the 52-week survival of the overall population was 71.4 ± 7.5%, significantly higher than IPF, survivals of anti-MPO patients with UIP pattern and IPF were similar. Forced vital capacity and diffusion lung capacity for CO significantly declined in 37.7 and 41.5% of cases, respectively, while disease progression at chest HRCT was observed in 45.2%. A careful clinical history and evaluation should always be performed in ILD patients with anti-MPO antibodies to quickly identify patients who are developing a systemic rheumatic disease.

Risk of progression of idiopathic pulmonary fibrosis to connective tissue disease: a long-term observational study in 527 patients

OBJECTIVE

Connective tissue disease (CTD) might occur during the course of idiopathic pulmonary fibrosis (IPF). Clinical factors associated with CTD development in IPF patients have still not been identified. We investigated which antibodies have a significant association with the development of CTD during the clinical course of IPF.

METHODS

We retrospectively reviewed the records of 527 patients with a first diagnosis of IPF between January 2007 and March 2014 and investigated the time to CTD development after IPF diagnosis in these patients.

RESULTS

CTD developed in 15 patients at a median of 2.1 years (range 1.2-4.8) after IPF diagnosis. All patients had anti-neutrophil cytoplasmic antibodies (ANCA) or autoantibodies that met the serology criteria for interstitial pneumonia with autoimmune features (IPAF). Survival duration for IPF patients with progression to CTD was 5.3 (3.8, 6.7) years, which was significantly longer than for IPF patients without progression to CTD [2.9 (1.7, 4.8), p = 0.001]. Independent risk factors for CTD development in IPF patients included female gender [adjusted hazard ratio (HR) 5.319, p = 0.0082], titer of rheumatoid factor (RF; adjusted HR, 1.006; p = 0.022), titer of anti-citrullinated protein antibody (ACPA; adjusted HR, 1.009; p = 0.0011), and titer of myeloperoxidase (MPO)-ANCA (adjusted HR, 1.02; p < 0.0001).

CONCLUSION

Progression to CTD is uncommon in IPF patients. However, a significant number of IPF patients with high titers of RF, ACPA, or MPO-ANCA progressed to CTD. RF, ACPA, and MPO-ANCA might be significantly associated with CTD development in IPF patients. Key Points • A significant number of IPF patients with high titers of RF, ACPA, or MPO-ANCA progressed to CTD. • IPF/UIP with high titers of RF, ACPA, or MPO-ANCA might be the initial clinical manifestation of CTD. • RF, ACPA, and MPO-ANCA may be significantly associated with the development of pulmonary fibrosis in patients with CTD.

Clinical features and long-term outcomes of interstitial lung disease with anti-neutrophil cytoplasmic antibody

Background

Patients with interstitial lung disease (ILD) are occasionally positive for anti-neutrophil cytoplasmic antibodies (ANCAs). Differences between ILDs secondary to microscopic polyangiitis (MPA) and isolated ANCA-positive idiopathic interstitial pneumonia (IIP) remain unclear. The aim of this study was to explore the differences in clinical features and outcomes between MPA-associated ILDs and isolated ANCA-positive IIPs.

Methods

We reviewed 1338 ILDs patients with available ANCA results and retrospectively analysed 80 patients who were ANCA-positive. MPA-associated ILDs (MPA-ILDs group) and isolated ANCA-positive IIPs (ANCA-IIPs group) were compared.

Results

Among 80 patients with ANCA-positive ILDs, 31 (38.75%) had MPA-ILDs, and 49 (61.25%) had isolated ANCA-positive IIPs. Compared with ANCA-IIPs group, patients in MPA-ILDs group had a higher proportion of fever (p = 0.006) and higher neutrophil count (p = 0.011), erythrocyte sedimentation rate (ESR) (p < 0.001) and C-reactive protein (CRP) (p = 0.005). Multivariable analysis showed that ESR level was an independent risk factor for mortality in all 80 ANCA-positive ILDs patients (HR 1.028, p = 0.001). Survival in MPA-ILDs group was lower than that in ANCA-IIPs group, and further stratified analysis revealed that ANCA-IIPs patients with elevated ESR or CRP had a worse prognosis than those with normal inflammation markers, with 5-year cumulative survival rates of 60.00%, 86.90% and 100.00% in MPA-ILDs and ANCA-IIPs with and without elevated inflammation markers, respectively.

Conclusions

Among patients with ANCA-positive ILDs, the prognoses of ANCA-IIPs with normal inflammation markers, ANCA-IIPs with elevated inflammation markers and MPA-ILDs were sequentially poorer. Therefore, stratified treatment should be considered in the management of ILDs patients positive for ANCAs.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12890-021-01451-4.

The Diagnosis and Treatment of Pulmonary Fibrosis

BACKGROUND

The different types of pulmonary fibrosis are a subgroup of the interstitial lung diseases (ILDs). They are associated with a chronic and often progressive course.

METHODS

This review is based on pertinent publications retrieved by a selective search in the EMBASE and PubMed databases, with an emphasis on articles published from 2000 to 2020.

RESULTS

The most common type of pulmonary fibrosis is idiopathic pulmonary fibrosis (IPF). Among other relevant types, the most important ones are fibrosing hypersensitivity pneumonitis (fHP) and ILDs associated with systemic diseases, all of which are rare and generally carry a poor prognosis. The essential prerequisite to accurate diagnosis is aninterdisciplinary approach, taking account of the clinical, histological, and radiological aspects. The main complications of pulmonary fibrosis are acute exacerbations and pulmonary hypertension; comorbidities are also of prognostic relevance. Treatment of pulmonary fibrosis depends on the subtype and clinical behavior. For IPF, antifibrotic therapy is indicated; fHP, on the other hand, is mainly treated by antigen avoidance and immune modulation. The predominant mode of treatment for systemic disease-associated pulmonary fibrosis is immune suppression. Antifibrotic agents can also be useful in the treatment of other types of progressivepulmonary fibrosis besides IPF.

CONCLUSION

The differential diagnosis of pulmonary fibrosis, though complex, is clinically essential, as different types of pulmonary fibrosis are treated differently.

Clinical Significance of Interstitial Lung Disease and Its Acute Exacerbation in Microscopic Polyangiitis

BACKGROUND

Presence of interstitial lung disease (ILD) is thought to be associated with mortality in microscopic polyangiitis (MPA); however, evidence on MPA-ILD remains lacking. Acute exacerbation (AE) refers to rapidly progressive, fatal respiratory deterioration that may develop in patients with various ILDs. No study has investigated the clinical significance of AE in MPA-ILD.

RESEARCH QUESTION

We aimed to determine the clinical picture and prognostic factors, the incidence of AE, and the risk factors in patients with MPA-ILD.

STUDY DESIGN AND METHODS

Eighty-four consecutive patients with MPA-ILD and 95 patients with MPA-non-ILD were analyzed. We also compared 80 patients with MPA-ILD and 80 patients with idiopathic interstitial pneumonia without myeloperoxidase-antineutrophil cytoplasmic antibody positivity (ILD alone), who were matched for age, sex, and chest high-resolution CT scan pattern.

RESULTS

The MPA-ILD group had a higher frequency of men and smokers and was associated with higher mortality than the MPA-non-ILD group. The matched MPA-ILD group had a higher mortality rate than the matched ILD alone group. There was no significant difference in AE incidence between the matched MPA-ILD and ILD alone groups (1-year AE cumulative incidence rate, 7.5% and 5.2%, respectively; P = .75). In the MPA-ILD group, a lower percent predicted FVC (%FVC) was independently associated with a higher mortality rate (hazard ratio [HR], 0.96 per 1% increase; P < .01) and a higher AE incidence rate (HR, 0.96 per 1% increase; P = .01). On multivariable Cox regression analysis with time-dependent covariates, developing AE during their clinical course was strongly associated with shorter survival (HR, 17.1; P < .001).

INTERPRETATION

MPA-ILD represented a distinct phenotype with poor prognosis. Lower %FVC was an independent prognostic factor. Patients with lower %FVC had a risk of developing AE, which was a strong prognostic determinant. The specific management for MPA-ILD and AE should be established.

MPO-ANCA positive interstitial pneumonia: Current knowledge and future perspectives

Although interstitial pneumonia is an important respiratory manifestation in microscopic polyangiitis (MPA), no studies have examined the detailed pathogenesis of interstitial pneumonia during the clinical course of MPA. In addition, it is considered that MPA develops at a certain incidence rate from myeloperoxidase (MPO)- antineutrophil cytoplasmic antibody (ANCA) positive interstitial pneumonia. However, there is a lack of consensus among pulmonologist and rheumatologist regarding whether MPO-ANCA positive interstitial pneumonia, which does not accompany other organ damage related to ANCA-associated vasculitis (AAV) other than interstitial pneumonia, should be included in AAV. In this review article, the clinical questions regarding MPO-ANCA positive interstitial pneumonia have been set, and evidence to date and problems to be solved in future are outlined.

Cardiac Involvement in Eosinophilic Granulomatosis With Polyangiitis: A Retrospective Study in the Chinese Population

Introduction: Cardiac involvement in eosinophilic granulomatosis with polyangiitis (EGPA) is associated with a poor prognosis and high mortality; however, few studies about cardiac involvement in EGPA in the Chinese population are available. We conducted this study to determine the clinical characteristics and overall outcomes of Chinese EGPA patients with cardiac involvement. Materials and Methods: We retrospectively collected the clinical data of 83 patients diagnosed with EGPA and analyzed the differences between the patients with and without cardiac involvement. Results: The prevalence of cardiac involvement in EGPA in this cohort was 27.7%. Compared with those without cardiac involvement, EGPA patients with cardiac involvement tended to have a younger age at onset (mean ± SD: 38.4 ± 10.5 vs. 42.1 ± 15.9 years, respectively, p = 0.039), higher eosinophil count (median [IQR]: 5810 [4020-11090] vs. 2880 [1530-6570] n/μL, respectively, p = 0.004), higher disease activity assessed using the Birmingham vasculitis activity score (BVAS) (median [IQR]: 20 [16-28] vs. 15 [12-18], respectively, p = 0.001), and poorer prognosis (Five Factor Score [FFS] ≥ 1: 100% vs. 38.3%, respectively, p = 0.001). In the cardiac involvement group, 43.5% of patients were asymptomatic, but cardiac abnormalities could be detected by cardiac examinations. With appropriate treatment, the overall outcomes of EGPA patients with cardiac involvement in our cohort were good, with only 3 (13.0%) patients dying in the acute phase and no patients dying during follow-up. Conclusions: Cardiac involvement in EGPA was associated with a younger age at onset, higher eosinophil count, higher disease activity, and a poorer prognosis. Comprehensive cardiac examinations and appropriate treatment are essential to improve the prognosis of those with cardiac involvement.

Diagnosis and management of connective tissue disease-associated interstitial lung disease in Australia and New Zealand: A position statement from the Thoracic Society of Australia and New Zealand

Pulmonary complications in CTD are common and can involve the interstitium, airways, pleura and pulmonary vasculature. ILD can occur in all CTD (CTD-ILD), and may vary from limited, non-progressive lung involvement, to fulminant, life-threatening disease. Given the potential for major adverse outcomes in CTD-ILD, accurate diagnosis, assessment and careful consideration of therapeutic intervention are a priority. Limited data are available to guide management decisions in CTD-ILD. Autoimmune-mediated pulmonary inflammation is considered a key pathobiological pathway in these disorders, and immunosuppressive therapy is generally regarded the cornerstone of treatment for severe and/or progressive CTD-ILD. However, the natural history of CTD-ILD in individual patients can be difficult to predict, and deciding who to treat, when and with what agent can be challenging. Establishing realistic therapeutic goals from both the patient and clinician perspective requires considerable expertise. The document aims to provide a framework for clinicians to aid in the assessment and management of ILD in the major CTD. A suggested approach to diagnosis and monitoring of CTD-ILD and, where available, evidence-based, disease-specific approaches to treatment have been provided.

2020 international consensus on ANCA testing beyond systemic vasculitis

This document follows up on a 2017 revised international consensus on anti-neutrophil cytoplasm antibodies (ANCA) testing in granulomatosis with polyangiitis and microscopic polyangiitis and focuses on the clinical and diagnostic value of ANCA detection in patients with connective tissue diseases, idiopathic interstitial pneumonia, autoimmune liver diseases, inflammatory bowel diseases, anti-glomerular basement membrane (GBM) disease, infections, malignancy, and during drug treatment. Current evidence suggests that in certain settings beyond systemic vasculitis, ANCA may have clinical, pathogenic and/or diagnostic relevance. Antigen-specific ANCA targeting proteinase-3 and myeloperoxidase should be tested by solid phase immunoassays in any patient with clinical features suggesting ANCA-associated vasculitis and in all patients with anti-GBM disease, idiopathic interstitial pneumonia, and infective endocarditis associated with nephritis, whereas in patients with other aforementioned disorders routine ANCA testing is not recommended. Among patients with autoimmune liver diseases or inflammatory bowel diseases, ANCA testing may be justified in patients with suspected autoimmune hepatitis type 1 who do not have conventional autoantibodies or in case of diagnostic uncertainty to discriminate ulcerative colitis from Crohn's disease. In these cases, ANCA should be tested by indirect immunofluorescence as the target antigens are not yet well characterized. Many questions concerning the optimal use of ANCA testing in patients without ANCA-associated vasculitis remain to be answered.

Patients with Interstitial Lung Disease Secondary to Autoimmune Diseases: How to Recognize Them?

The diagnostic assessment of patients with Interstitial Lung Disease (ILD) can be challenging due to the large number of possible causes. Moreover, the diagnostic approach can be limited by the severity of the disease, which may not allow invasive exams. To overcome this issue, the referral centers for ILD organized Multidisciplinary Teams (MDTs), including physicians and experts in complementary discipline, to discuss the management of doubtful cases of ILD. MDT is currently considered the gold standard for ILD diagnosis, but it is not often simple to organize and, furthermore, rheumatologists are still not always included. In fact, even if rheumatologic conditions represent a common cause of ILD, they are sometimes difficult to recognize, considering the variegated clinical features and their association with all possible radiographic patterns of ILD. The first objective of this review is to describe the clinical, laboratory, and instrumental tests that can drive a diagnosis toward a possible rheumatic disease. The secondary objective is to propose a set of first-line tests to perform in all patients in order to recognize any possible rheumatic conditions underlying ILD.

Clinical implications of ANCA positivity in idiopathic pulmonary fibrosis patients

The diagnostic process of idiopathic interstitial pneumonias (IIPs) is complex and the underlying mechanisms that participate in these diseases still need to be fully understood. In 2015, the European Respiratory Society/American Thoracic Society Task Force on Undifferentiated Forms of Connective Tissue Disease-Associated Interstitial Lung Disease introduced the term “interstitial pneumonia with autoimmune features” (IPAF) to identify subjects with IIP and features suggesting background autoimmunity but not characterisable connective tissue disease (CTD) [1]. The need for a proper clinical, serological and morphological assessment of IIP was highlighted to identify potential subjects with IPAF and CTD-ILD. However, the measurement of anti-neutrophil cytoplasmic antibodies (ANCAs) is not included in the definition of IPAF and ANCA serological testing is only recommended in idiopathic pulmonary fibrosis (IPF) when a clinical suspicion of vasculitis exists [2]. As current research evaluates the prognostic relevance of autoimmune features in IIP, the clinical importance of ANCA positivity still needs to be determined.

ANCA positivity is uncommon in North American IPF patients. However, women with IPF who areMPO-positive have a considerable risk for developing clinical manifestations of vasculitis.http://bit.ly/2RlsQNP

Management of ANCA associated vasculitis

Anti-neutrophil cytoplasmic antibody (ANCA) associated vasculitis (AAV) is a small to medium vessel vasculitis associated with excess morbidity and mortality. This review explores how management of AAV has evolved over the past two decades with pivotal randomized controlled trials shaping the management of induction and maintenance of remission. Contemporary AAV care is characterized by approaches that minimize the cumulative exposure to cyclophosphamide and glucocorticoids, increasingly use rituximab for remission induction and maintenance, and consider therapies with less toxicity (for example, methotrexate, mycophenolate mofetil) for manifestations of AAV that do not threaten organ function or survival. Simultaneously, improvements in outcomes, such as renal and overall survival, have been observed. Additional trials and observational studies evaluating the comparative effectiveness of agents for AAV in various patient subgroups are needed. Prospective studies are necessary to assess the effect of psychosocial interventions on patient reported outcomes in AAV. Despite the expanding array of treatments for AAV, little guidance on how to personalize AAV care is available to physicians.