Clinical features and prognostic predictors in patients with rheumatic diseases complicated by Pneumocystis pneumonia

To investigate the clinical outcomes and risk factors of mortality in patients with rheumatic diseases complicated by Pneumocystis pneumonia (PCP).Between November 2015 and April 2021, patients with rheumatic diseases with PCP in a tertiary referral hospital were retrospectively enrolled. The diagnosis of PCP requires the fulfillment of clinical, radiographic, and microbiological criteria. Factors associated with in-hospital, 30-day, and 90-day mortality were evaluated.A total of 128 patients with rheumatic diseases who had a positive quantitative polymerase chain reaction assay for Pneumocystis jirovecii were screened, and 72 patients were included in the final analysis. The median (interquartile range [IQR]) pneumonia severity index (PSI) was 101.5 (77.0-132.0). The median (IQR) adjunctive corticosteroid dosage was 0.6 (0.4-0.9) mg/kg/day prednisolone equivalent. The receiver operating characteristic curve analysis showed that the optimal cutoff point of median adjunctive corticosteroid dosage was 0.6 mg/kg/day to predict in-hospital, 30-day, and 90-day mortality. In the multivariable logistic regression analysis, median adjunctive corticosteroid dosage ≥0.6 mg/kg/day and PSI90 were independent factors of in-hospital, 30-day, and 90-day mortality.A median adjunctive corticosteroid dosage of ≥0.6 mg/kg/day might be associated with mortality in patients with rheumatic diseases complicated by PCP.