Bacterial endocarditis complicating systemic lupus erythematosus.

Culture proven bacterial endocarditis occurred in 6 of 571 patients with systemic lupus erythematosus (SLE) admitted to the National Institutes of Health (NIH). Although 4 of the patients had a murmur noted on examination prior to developing endocarditis, only one of the 6 had a recognized valvular abnormality. Bacterial endocarditis followed dental procedures in 2 of the 6 patients; no precipitating events were recorded in the remaining 4. M-mode and 2-D echocardiography of 20 unselected SLE patients did not reveal previously unrecognized cardiac disease. There was an unexpectedly high frequency of bacterial endocarditis among SLE patients relative to all other connective tissue disease patients seen at the NIH.