Antibiotic susceptibility profiles for group B streptococci isolated from neonates, 1995-1998

Antibiotic susceptibility profiles were analyzed for 119 invasive and 227 c olonizing strains of group B streptococci isolated from neonates at 6 US ac ademic centers, All strains were susceptible to penicillin, vancomycin, chl oramphenicol, and cefotaxime, The rate of resistance to erythromycin was 20 .2% and to clindamycin was 6.9%. Resistance to erythromycin increased in 19 97, Type V strains were more resistant to erythromycin than were type Ia (P = .003) and type Tb (P = .004) strains and were more resistant to clindamy cin than were type Ia (P < .001), type Tb (P = .01), and type III (P = .001 ) strains. Resistance rates varied with geographic region: in California, t here were high rates of resistance to erythromycin and clindamycin (32% and 12%, respectively), and low rates in Florida (8.5% and 2.1%, respectively) . Penicillin continues to be the drug of choice for treatment of group B st reptococcus infection. For women who are penicillin intolerant, however, th e selection of an alternative antibiotic should be guided by contemporary r esistence patterns observed in that region.