[Necrotising endocarditis of mitral valve due to Staphylococcus lugdunensis]

Staphylococcus lugdunensis is an infrequent cause of infective endocarditis (IE) and usually involves native valves of the heart. It causes life-threatening events such as rupture of cardiac valve or cerebral or pulmonary embolism due to necrosis on the endocardial tissue involved by the bacteria. Antibiotic therapy without cardiac surgery or delayed cardiac surgery usually follows a fatal course in S. lugdunensis endocarditis. In this report the first case of S. lugdunensis endocarditis from Turkey was presented. A 37-year-old man was admitted to the emergency department with a 2-weeks history of fever chills and accompanying intermittent pain on the left side of the thorax. Other than recurrent folliculitis continuing for 20 years, his history was unremarkable. Echocardiography revealed vegetation on the mitral valve of the patient and vancomycin plus gentamicin were initiated with the diagnosis of IE. All blood cultures (5 sets) taken on admission and within the initial 48 hours of the antibiotic therapy yielded S. lugdunensis. According to the susceptibility test results, the antibiotic therapy was switched to ampicillin-sulbactam plus rifampin. Blood cultures became negative after the third day of therapy, however, cardiac failure was emerged due to rupture of mitral valve and chorda tendiniea on the 12th day of the therapy. Cardiac surgery revealed that mitral valve and surrounding tissue of the valve were evidently necrotic and fragile, anterior leaflet of the mitral valve was covered with vegetation, posterior leaflet and chorda tendiniea were ruptured. Vegetation was removed and the destructed mitral valve was replaced with a mechanical valve. Vegetation culture remained sterile, however, antibiotics were switched to vancomycin plus rifampin due to persistent fever on the 21st day of the therapy (9th day of operation). Fever resolved four days after the antibiotic switch. Antibiotics were stopped on the 9th weeks of admission and the patient was discharged. He had no problem in follow-up controls for one year. In conclusion, proper antibiotic therapy combined with early cardiac surgery seems to be the optimal therapeutic approach in IE caused by S. lugdunensis.