Streptococcal endocarditis temporally related to transesophageal echocardiography. A case of streptococcal sanguis endocarditis temporally related to a transesophageal echocardiogram is reported; and the literature on the incidence of bacteremia occurring during transesophageal echocardiography is reviewed. On the basis of this case and review of the literature, a reevaluation of the current guidelines for endocarditis prophylaxis during this procedure is recommended. 