Frenemies within: An Endocarditis Case in Behçet's Disease.

A 57-year female patient diagnosed with Behçet's disease, on azathioprine, was noticed to have at a routine examination antinuclear and antiphospholipid antibodies. An overlapping lupus-like syndrome was diagnosed; hydroxychloroquine and aspirin were added. Three years later, the patient presented with dyspnea and sweating, with no fever. A cardiac bruit was noted; a giant vegetation was detected by echocardiography. Laboratory revealed severe thrombocytopenia, antiphospholipid antibodies and low complement. Blood cultures were positive for serology and also revealed a chronic infection. Antibiotic therapy, low-dose anticoagulation and control of the underlying disease mildly improved the platelet count, which fully recovered only after cardiac valve replacement. However, the Behçet's disease, initially quiescent, flared after the therapy of infections. We discuss potential links between Behçet's disease and the occurrence of antinuclear and antiphospholipid antibodies and endocarditis in this setting. We also highlight the differences between the endocarditis in Behçet's disease, antiphospholipid syndrome, and infection, respectively. Intracellular infections may modify the presentation of autoimmune diseases. Confounding clinical features of persistent infection and non-bacterial thrombotic endocarditis in Behçet's disease warrant further insight.