MPO and microscopic polyangiitis: The presence of myeloperoxidase (MPO) specific antineutrophil cytoplasmic antibodies (ANCA), a usual interstitial pneumonia (UIP) pattern on high resolution computed tomography (HRCT), and induction therapy with glucocorticoids have been identified as unfavorable prognostic factors in patients with MPA-ILD (Homma et al., 2013; Comarmond et al., 2014; Fernandez Casares et al., 2015; Watanabe et al., 2019).