studies of 28 enterococci isolated from patients with enterococcal bacteremia suggested three possible mechanisms for this in vivo antibiotic failure : ( i ) a relatively high level of resistance to cephalothin among all enterococci and especially those characterized as streptococcus faecium , ( ii ) a significant incidence of high-level resistance to the aminoglycosides among certain strains of enterococci , and ( iii ) a failure of synergism to occur when cephalothin concentrations fall below the minimal inhibitory concentration of the enterococcus , as occurs during the in vivo metabolism and excretion of this antibiotic when given in standard doses for endocarditis .
C0025519
metabolism
C0221102
excretion