Systemic lupus erythematosus (SLE) is an autoimmune disease, characterized by dysregulation of the innate and adaptive immune systems, production of autoantibodies, and tissue damage resulting from chronic inflammation. The treatment includes the use of non-steroidal anti-inflammatory and anti-malarial drugs, corticosteroids and immunosuppressive agents. Despite great improvements in reducing mortality in SLE, the mortality due to infections remains unchanged, constituting the cause of death in 1 out of 3 SLE patients.
Multiple risk factors for infection have been reported. They include immunological disorders due to lupus and its therapy, particularly immunosuppressive and cytotoxic medications. Lupus disease activity, measured by the SLE disease activity index (SLEDAI), is also an important risk factor for infection. The risk is also dependent on the degree of immunosuppression.