Bacterial endocarditis; unusual case with blood cultures positive for Brucella abortus and viridans Streptococcus

THE CLINICAL, bacteriologic, immunologic, and pathologic criteria necessary for establishing the diagnosis of bacterial endocarditis are difficult to fulfill. Fortunately, since the advent of antibiotics the mortality due to bacterial endocarditis has diminished markedly, so that the majority of patients now recover, whereas previously recovery was a rare event. At the autopsy table it was possible to demonstrate the characteristic valvular vegetations and to culture the causative bacteria from the vegetations. At the present time more and more reliance must be placed on the clinical, bacteriologic, and immunologic findings in an effort to establish the correct diagnosis and the etiologic bacteria, because most patients properly treated do not reach the pathologist. Correct bacteriologic diagnosis is a necessity, because the choice of antibiotic to be employed in treatment depends on the particular bacteria responsible for the infection. There are very few reported cases of bacterial endocarditis due to Brucella. Smith and