Observational Study of Clinical Features and Outcome of Interstitial Lung Disease With Anti-neutrophil Cytoplasmic Antibody in Chinese Patients.
Conditions: Interstitial Lung Disease, Anti-Neutrophil Cytoplasmic Antibody-Associated Vasculitis
Sponsor: Peking Union Medical College Hospital

 
 
 
 
 
 
 
Title: 
Observational Study of Clinical Features and Outcome 
of Interstitial Lung Disease with Anti-neutrophil 
Cytoplasmic Antibody in Chinese Patients 
 
NCT number: 
 
NCT04413149 
 
Date: 
 
2020-6-20 
 
 
 

Background and Objectives 
Anti-neutrophil cytoplasmic antibody (ANCA) is occasionally positive in patients 
with interstitial lung disease (ILD), including patients with a diagnosis of ANCA-
associated vasculitis (AAV) and patients with isolated ANCA-positive idiopathic 
interstitial pneumonia (IIP). Their clinical and prognostic differences are not well 
known. The purpose of this study is to investigate the clinical features and long-term 
outcome of ANCA-positive ILD and assess the difference between microscopic 
polyangiitis (MPA) associated ILD and isolated ANCA-positive IIP. 
 
Methods 
Study Population  
Interstitial lung disease patients with anti-neutrophil cytoplasmic antibody.  
 
Criteria  
Inclusion Criteria:  
l Males and females  
l Aged from 18 to 85 years with informed consent  
l Have a diagnosis of ILD based on clinical symptoms and radiologic features, 
with or without histopathologic results  
l Have available ANCA testing results during the first visit and follow-up 
period  
Exclusion Criteria:  
l Connective tissue disease associated ILD 
l ILD induced by drug, environment, or occupational exposure 
l Hypersensitivity pneumonitis and sarcoidosis  
 
Group Information 
In all the patients with ANCA-positive ILD, those who were diagnosed with MPA 
according to 2012 Chapel Hill consensus criteria are defined as MPA-ILD group, 

and patients with isolated ANCA-positivity who did not fulfill the MPA criteria are 
classified as ANCA-IIP group 
 
Data collection 
Baseline information at the time of initial diagnosis was obtained and the 
following items were analyzed:  
l demographics information (age, gender) 
l clinical course 
l clinical symptoms and signs 
l laboratory findings (blood and urine routine, liver and renal function tests, 
erythrocyte sedimentation rate [ESR], C reactive protein [CRP]) 
l rheumatoid factor 
l serologic autoantibodies [ANA, anti-ENA, ANCA, anti-CCP]) 
l pulmonary function tests (PFTs) (ventilation and diffusion capacity test) 
l chest high-resolution computed tomography (HRCT)  
ANCA was assessed by indirect immunofluorescence while MPO-ANCA and 
PR3-ANCA titers were measured by ELISA. 
Chest HRCT images were evaluated together by more than two pulmonologists 
and radiologists blinded to clinical and histopathological information. The HRCT 
scans were analyzed for the following characteristics: ground-glass opacity, 
consolidation, reticular pattern, honeycombing, traction bronchiectasis, interlobular 
septal thickening, curved linear opacity, pleural thickening, etc. 
The patients were followed up at least once a year and basic laboratory tests, 
serologic autoantibodies, PFT and chest HRCT were evaluated routinely. The follow-
up period ended in April 2019 and the outcomes were defined as death from all causes 
and lung transplantation.  
 
Statistical Analysis Plan 
All data are analyzed using statistical analysis software (version 24.0, SPSS, IBM 

Corporation). Normally distributed variables are presented as means ± SD, and 
Student t test is used for comparisons. Continuous, non-normally distributed data are 
presented as median with interquartile ranges (IQR), and the Mann-Whitney U test is 
used for comparisons. Categorical variables are expressed as number (%), and χ2 test 
or Fisher’s exact test is used for comparisons. Survival analysis is performed by 
Kaplan-Meier analysis using log-rank test. Cox models are used to examine the 
association between baseline characteristics and mortality. P values are two-sided, 
and P < 0.05 is considered statistically significant.