Interstitial lung disease with ANCA-associated vasculitis (AAV-ILD): Clinical features and survival compared to patients with ILD associated with systemic sclerosis and IPF

Introduction: Pulmonary involvement in ANCA-associated vasculitis is frequent, however ILD are rare manifestation. There is no current consensus on specific therapy, and it is unknown if its natural history is similar to that of patients with IPF or other forms of CTD-ILD. The aims of our study are to describe clinical, functional features of patients with VAA-ILD and comparison to others ILD. Method: Retrospective cohort study. Descriptive and comparative analysis was performed in tree group: AAV- ILD, SSc -ILD and IPF. Kaplan-Meier estimator was used for survival analysis and the Log-Rank test for comparison of survival. Results: 24 patients diagnosed with AAV-ILD, 25 with ILD-SSc and 73 with IPF were included. All patients had positive anti-myeloperoxidase (MPO) antibodies. The UIP pattern was the most frequent (79%). There were no differences in the survival of patients with ILD-SSc and AAV-ILD. While patients with IPF presented worse survival. 26.1% of the patients were initially diagnosed with ILD and subsequently of AAV the survival of the subgroup was similar to IPF, figure 1. Conclusion: In our cohort the population the main radiological pattern in AAV- ILD was UIP associated with positive MPO Ab. AAV-ILD and IPF were similar in age, however, the survival of the AAV-ILD group was similar to SSc -ILD, with a better prognosis than IPF.