MPO and interstitial lung disease: Some reported findings suggest that patients with isolated ANCA-ILD also have a poor prognosis or a progressive course [7,8,18,26,27], with related factors overlapping those previously described in AAV-ILD patients [6,24,26,27,29], in line with our results, along with the addition of elevated inflammation markers [4,5,6,7,8,9,29], anti-MPO positivity [7], or high ANCA titers (>50 EU) [28] in some cohorts.