Objective To analyse the clinical features and prognostic factors of microscopic polyangiitis (MPA) with diffuse alveolar haemorrhage (DAH). Methods We conducted a retrospective study of 92 patients diagnosed with MPA with DAH at the First Affiliated Hospital of Chongqing Medical University between March 1, 2012, and March 12, 2018. The cumulative survival rate was analyzed by the Kaplan-Meier method, and survival curves were drawn. A Cox hazard model was used to determine the prognostic factors for survival by univariate and multivariate analysis. Results The mean age at the onset of MPA with DAH was 66.32 years. Among the 92 MPA with DAH patients who were followed up, 41 (44.57%) were critical illness and 79 (85.87%) had pulmonary and renal involvement. The cumulative survival rates of the 92 patients at 1, 3, and 5 years were 63.7%, 51.2%, and 47.3%, respectively, and the median survival time was 46 months. In the multivariate analysis, age>65 years (HR=4.303, 95% CI: 1.940~9.547), sCr>500 μmol/L (HR=2.043, 95% CI: 1.051~3.972), PaO2/FiO2<300 mmHg (HR=4.095, 95% CI: 1.966~8.525), and lung involvement area≥50% (HR=2.928, 95% CI: 1.399~6.129) were independent prognostic factors (P<0.05). Conclusion The incidence and mortality of DAH are high in MPA patients. Age>65 years, sCr>500 μmol/L, PaO2/FiO2<300 mmHg and lung involvement area≥50% are independent prognostic factors for MPA with DAH.

Objective To analyze prognostic factors of antisynthetase syndrome (ASS)‐related interstitial lung disease (ILD). Methods We retrospectively collected the data of 77 inpatients with ASS‐ILD at our hospital from January 1, 2018, to January 1, 2021. The improvement/stability group and deterioration/death group were defined according to their follow‐up outcome. Clinical data of the 2 groups were compared. Univariate analysis was adopted to screen the possible prognostic factors and then logistic regression was used for multivariate analysis. Result After 6 to 42 months of follow‐up, 52 patients (67.5%) were classified into the improvement/stability group, and 25 patients (32.5%) were classified into the deterioration/death group. According to the multivariate stepwise logistic regression analysis, respiratory failure (odds ratio [OR] = 6.71, 95% CI: 1.64–27.38, P = .008) and elevated muscle enzymes (OR = 4.31, 95% CI: 1.03–18.05, P = .045) were found to be independent risk factors, while mechanic's hands (OR = 0.06, 95% CI: 0.01–0.37, P = .003) and anti‐Jo‐1 antibody (OR = 0.24, 95% CI: 0.06–0.93, P = .039) were protective factors. Conclusion The prognostic assessment of ASS‐ILD patients should be emphasized. Patients with a poor prognosis should be identified early based on their risk factors to guide clinical management decisions.