Measurement of serum bactericidal activity and use of vancomycin for treatment of nutritionally variant streptococcal bacteremia.

Nutritionally variant streptococci appear more resistant to antimicrobial treatment that other viridans streptococci. We describe a patient with nutritionally variant streptococcal bacteremia who responded to treatment with vancomycin. Results of serum bactericidal tests did not vary in six different media and correlated minimally with the serum concentration of vancomycin.