Background and aims To study the risk factors of pulmonary embolism (PE) in SLE patients.

Methods 1739 SLE patients admitted to Renji Hospital between 2005 and 2014(0.9% prevalence) were enrolled. The clinical data (SLEDAI) and lab data (anti-dsDNA antibody, D-Dimer, antiphospholipid antibody) were analysed.

Results Nine cases were found to be accompanied with pulmonary hypertension, and nine cases were with antiphospholipid syndromes simultaneously. Almost every patient had symptoms of chest pain or shortness of breath, and disease activities assessed by SLEDAI were at moderate-high level when the PE occurred. Accordingly, increased anti-dsDNA antibody was found in ten cases, and heavy urinary protein was found in six cases(>1g/24 hour). High levels of D-Dimer were encountered only in five cases, and were negative in up to 25% of cases. Successful recovery was noted in all patients treated with steroid and anticoagulant. One patient died at one-year follow-up. Of those with PE (n=16), the ratio of positive aPL, elevated D-Di, and concurrent PAH were higer than those without PE (p=0.000; p=0.012; p=0.000, respectively).

Conclusions Unexplained chest pain and shortness of breath are two major symptoms indicating PE in SLE patients. Patients whose aPL, D-Dimer were elevated, or concurrent have pulmonary hypertension, are at high risk for thrombosis and subsequent pulmonary embolism.