Antiphospholipid syndrome masquerading as a case of infective endocarditis.

A 54-year-old Caucasian woman presented with an episode of loss of consciousness and dysphasia. MRI revealed a number of ischaemic foci indicating an embolic source. Echocardiography showed a mitral valve vegetation. After taking three sets of blood cultures, she was started on empirical treatment for infective endocarditis. The blood cultures remained negative and a presumed diagnosis of culture-negative endocarditis was entertained. However, despite the antibiotic therapy, the patient deteriorated further. Subsequently the patient was found to be positive for antiphospholipid antibodies. Eventually, after a convoluted hospital stay, a diagnosis of antiphospholipid syndrome complicated by Libman-Sacks endocarditis was reached. The patient was treated with steroids and anticoagulation with dramatic improvement.