Infective endocarditis culture-negative

Culture negative endocarditis—Describes a patient in whom a clinical diagnosis of infective endocarditis is likely, but blood cultures do not yield a pathogen. 

Albrich WC, Kraft C, Fisk T, et al. A mechanic with a bad valve Blood-culture-negative endocarditis. Lancet Infect Dis. 2004 4 777-784. 

Duration - Duration of therapy varies with the type and severity of infection as well as the overall condition of the patient therefore, determine duration by the clinical and bacteriological response of the patient. In severe staphylococcal infections, continue nafcillin therapy for at least 14 days. Continue therapy for at least 48 hours after the patient has become afebrile and asymptomatic and cultures are negative. The treatment of endocarditis and osteomyelitis may require a longer duration of therapy. 

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