title: Antibiotic resistance patterns in invasive group B streptococcal isolates.
abstract: Antibiotics are used for both group B streptococcal (GBS) prevention and treatment. Active population-based surveillance for invasive GBS disease was conducted in four states during 1996-2003. Of 3813 case-isolates, 91.0% (3471) were serotyped, 77.1% (2937) had susceptibility testing, and 46.6% (3471) had both. All were sensitive to penicillin, ampicillin, cefazolin, cefotaxime, and vancomycin. Clindamycin and erythromycin resistance was 12.7% and 25.6%, respectively, and associated with serotype V (P < .001). Clindamycin resistance increased from 10.5% to 15.0% (X(2) for trend 12.70; P < .001); inducible clindamycin resistance was associated with the erm genotype. Erythromycin resistance increased from 15.8% to 32.8% (X(2) for trend 55.46; P < .001). While GBS remains susceptible to beta-lactams, resistance to alternative agents such as erythromycin and clindamycin is an increasing concern.
authors.affiliation: Infectious Disease Epidemiology, Prevention and Control Division, Minnesota Department of Health, Saint Paul, MN 55164, USA.
authors.forename: Mei L
authors.initials: ML
authors.lastname: Castor
authors.forename: Cynthia G
authors.initials: CG
authors.lastname: Whitney
authors.forename: Kathryn
authors.initials: K
authors.lastname: Como-Sabetti
authors.forename: Richard R
authors.initials: RR
authors.lastname: Facklam
authors.forename: Patricia
authors.initials: P
authors.lastname: Ferrieri
authors.forename: Joanne M
authors.initials: JM
authors.lastname: Bartkus
authors.forename: Billie A
authors.initials: BA
authors.lastname: Juni
authors.forename: Paul R
authors.initials: PR
authors.lastname: Cieslak
authors.forename: Monica M
authors.initials: MM
authors.lastname: Farley
authors.forename: Nellie B
authors.initials: NB
authors.lastname: Dumas
authors.forename: Stephanie J
authors.initials: SJ
authors.lastname: Schrag
authors.forename: Ruth
authors.initials: R
authors.lastname: Lynfield
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D015169:Colony Count, Microbial; D004305:Dose-Response Relationship, Drug; D024881:Drug Resistance, Bacterial; D006801:Humans; D008826:Microbial Sensitivity Tests; D015995:Prevalence; D011634:Public Health; D012703:Serotyping; D013290:Streptococcal Infections / Q000188:drug therapy*; D013292:Streptococcus agalactiae / Q000145:classification / Q000187:drug effects*
chemical_list: D000900:Anti-Bacterial Agents