Antibiotic resistance patterns of group B streptococcus in antenatal genital cultures

OBJECTIVE: To identify the antibiotic susceptibility patterns of group B st reptococcus (GBS) isolated from antenatal genital screening cultures. STUDY DESIGN: One hundred thirty-five sequential GBS isolates underwent sus ceptibility testing by Kirby-Bauer disk diffusion to a variety of commonly used antibiotics. RESULTS: All isolates were susceptible to cefazolin, chloramphenicol and va ncomycin. Resistance to clindamycin and erthromycin, the currently recommen ded alternative antibiotics for intrapartum GBS prophylaxis in penicillin-a llergic women, was found in 8.2% and 9.6% of GBS isolates tested, respectiv ely. CONCLUSION: These findings raise concerns regarding the need for both confi rmation of a history of penicillin allergy in pregnant women and performanc e of antibiotic susceptibility testing on GBS isolated in genital screening cultures from penicillin-allergic patients.