Patterns of lung diseases predict survival in patients with MPO-ANCA-associated vasculitis: a single-center retrospective study

Objectives This study aimed to explore differences in clinical features and prognosis among patients with varied myeloperoxidase (MPO) antineutrophil cytoplasmic antibody-associated vasculitis (MPO-AAV) associated lung diseases. Methods Patients with MPO-AAV-associated lung diseases were enrolled in this retrospective cohort study at a single center. Clinical features and laboratory data at the time of diagnosis were compared among patients with various lung disease patterns. Kaplan–Meier and Cox regression analyses were performed to analyze overall survival. Results A total of 155 patients were finally included and categorized into five groups, as follows: 72 had a usual interstitial pneumonia (UIP) pattern, 40 had non-UIP interstitial pneumonia, 18 had bronchiectasis (BR), 13 had necrotizing granuloma (NG), and 12 had diffuse alveolar hemorrhage (DAH). Among the five groups, patients with DAH had higher dyspnea and hemoptysis frequencies, lower PaO 2 /FiO 2 levels, elevated C-reactive protein levels, and the poorest prognosis. The overall survival (OS) in the DAH group (median OS: 3.2 months) was significantly poorer than that in the NG group (median OS: not reached, log rank P