ANTIMICROBIAL SUSCEPTIBILITY OF VIRIDANS GROUP STREPTOCOCCI

A total of 68 viridans group streptococci, including 31 Streptococcus sanguis, 12 S. mitis, 3 S. salivarius, and 8 S. milleri from blood, an d an additional 14 S. milleri from abscesses and normally sterile site s, were tested against penicillin, amoxicillin, cefazolin, ceftriaxone , meropenem, clindamycin, quinupristin/dalfopristin, rifampin, levoflo xacin, ofloxacin, vancomycin, and gentamicin with the microdilution me thod. The susceptibility rates for S. sanguis were: penicillin, 74%; a moxicillin, 84%; ceftriaxone, 94%; clindamycin, 87%, and vancomycin, 1 00%. The susceptibility rates for S. mitis were: penicillin, 42%; amox icillin, 67%; ceftriaxone, 58%; clindamycin, 100%; and vancomycin, 100 %. The susceptibility rates for S. milleri were: penicillin, 100%, amo xicillin, 100%; ceftriaxone, 100%, clindamycin, 100%; and vancomycin, 100%. Two of the three isolates of S. salivarius were susceptible to p enicillin, amoxicillin, and ceftriaxone; all were susceptible to clind amycin and vancomycin. Levofloxacin, quinupristin/dalfopristin, and ri fampin were highly active against all isolates. (C) 1997 Elsevier Scie nce Inc.