Therapy of streptococcal endocarditis: correlation of animal model and clinical studies

Streptococci (viridans group, Streptococcus bovis, enterococci still account for the majority of cases of infective endocarditis in the non-addict population. Experimental animal models of endocarditis have been used (primarily in rabbits) to delineate the major therapeutic principles of this disease; viz. bactericidal antimicrobial agents must be given parenterally in high dosages for prolonged period of time. Overall, there is a good correlation between results obtained by: (1) in-vitro susceptibility testing (especially killing kinetics in broth); (2) therapeutic comparisons in experimental animal models and (3) clinical trials of different antimicrobial regimens in humans with streptococcal endocarditis. This review contrasts the published results obtained in vivo with experimental animal models to those obtained with various therapeutic approaches to streptococcal endocarditis in humans. The contribution of animal models to current therapeutic recommendations in man is underscored.