Pneumocystis jirovecii pneumonia in autoimmune rheumatic diseases: a nationwide population-based study.

Underlying ARD significantly predisposes patients to PJP, with PM/DM posing the highest threat. In addition to underlying disease, comorbidities and concomitant immunosuppressants are major risks. The strongest risk is recent daily steroid dose of >10 mg. Mycophenolate seems to be a more prominent risk factor than cyclophosphamide. Key Points • Autoimmune rheumatic diseases (ARD) significantly increased the overall risk of PJP, and so did each individual ARD. • Use of steroids, mycophenolate, cyclophosphamide, biological agents, methotrexate, and cyclosporine all significantly increased risk of PJP. • Male, elderly, malignancy, HIV, and interstitial lung disease are also related to increased risk of PJP. • Underlying ARD, comorbidities, and use of immunosuppressant should all be considered in determining the overall risk of PJP.