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Original article

Vol. 144 No. 1112 (2014)

Serotype distribution and antimicrobial susceptibility of group B streptococci in pregnant women: results from a Swiss tertiary centre

  • Simone Fröhlicher
  • Gabriela Reichen-Fahrni
  • Martin Müller
  • Daniel Surbek
  • Sara Droz
  • Barbara Spellerberg
  • Parham Sendi
Cite this as:
Swiss Med Wkly. 2014;144:w13935


OBJECTIVE: To evaluate the rates of penicillin, clindamycin and erythromycin resistance and the serotype distribution among isolates of group B streptococcus (GBS) obtained from pregnant women at the University Hospital of Bern in Switzerland.

METHODS: We prospectively collected screening samples for GBS colonisation at the University Women’s Hospital Bern, Switzerland, between March 2009 and August 2010. We included 364 GBS isolates collected from vaginal, cervical or vaginal-perianal swabs at any gestation time. The minimal inhibitory concentrations for penicillin, clindamycin and erythromycin were established using Etest with 24 hours of incubation, and inducible clindamycin resistance was tested with double disk diffusion tests. Serotyping was done with a rapid latex agglutination test or, if not conclusive, with polymerase chain-reaction (PCR) testing. We looked for significant associations between resistance patterns, age groups, serotype and ethnicity.

RESULTS: All isolates were susceptible to penicillin. Resistance rates were 14.5% for erythromycin and 8.2% for clindamycin. Of 364 isolates, 5.8% were susceptible to clindamycin but not to erythromycin, although demonstrating inducible clindamycin resistance. Hence, the final reported clindamycin resistance rate was 14%. Serotype III was the most frequent serotype (29%), followed by V (25%) and Ia (19%). Serotype V was associated with erythromycin resistance (p = 0.0007). In comparison with all other ethnicities, patients from Asia showed a higher proportion of erythromycin and clindamycin resistance (p = 0.018). No significant association between resistance patterns and age groups was found.

CONCLUSION: In pregnant women with GBS colonisation, penicillin is the antibiotic of choice for intrapartum prophylaxis to prevent neonatal early-onset GBS sepsis. In women with penicillin allergy and at high risk for anaphylactic reaction, clindamycin may be an alternative. The resistance rate for clindamycin at our institution was 14%; therefore, susceptibility must be tested before administration.


  1. Baker CJ, Barrett FF. Transmission of group B streptococci among parturient women and their neonates. The Journal of pediatrics. 1973;83:919–25.
  2. Barcaite E, Bartusevicius A, Tameliene R, Kliucinskas M, Maleckiene L, Nadisauskiene R. Prevalence of maternal group B streptococcal colonisation in European countries. Acta obstetricia et gynecologica Scandinavica. 2008;87:260–71.
  3. Rausch AV, Gross A, Droz S, Bodmer T, Surbek DV. Group B Streptococcus colonization in pregnancy: prevalence and prevention strategies of neonatal sepsis. J Perinat Med. 2009;37:124–9.
  4. Anthony BF. Carriage of group B streptococci during pregnancy: a puzzler. The J Infect Dis. 1982;145:789–93.
  5. Renner RM, Renner A, Schmid S, Hoesli I, Nars P, Holzgreve W, et al. Efficacy of a strategy to prevent neonatal early-onset group B streptococcal (GBS) sepsis. J Perinat Med. 2006;34:32–8.
  6. Verani JR, McGee L, Schrag SJ. Prevention of perinatal group B streptococcal disease--revised guidelines from CDC, 2010. MMWR. Recommendations and reports: Morbidity and mortality weekly report. Recommendations and reports / Centers for Disease Control. 2010;59:1–36.
  7. Schrag SJ, Zywicki S, Farley MM, Reingold AL, Harrison LH, Lefkowitz LB, et al. Group B streptococcal disease in the era of intrapartum antibiotic prophylaxis. N Engl J Med. 2000;342:15–20.
  8. Dahesh S, Hensler ME, Van Sorge NM, Gertz RE, Jr., Schrag S, Nizet V, et al. Point mutation in the group B streptococcal pbp2x gene conferring decreased susceptibility to beta-lactam antibiotics. Antimicrob Agents Chemother. 2008;52:2915–8.
  9. Kimura K, Suzuki S, Wachino J, Kurokawa H, Yamane K, Shibata N, et al. First molecular characterization of group B streptococci with reduced penicillin susceptibility. Antimicrob Agents Chemother. 2008;52:2890–7.
  10. Gaudreau C, Lecours R, Ismail J, Gagnon S, Jette L, Roger M. Prosthetic hip joint infection with a Streptococcus agalactiae isolate not susceptible to penicillin G and ceftriaxone. J antimicrob Chemother. 2010;65:594–5.
  11. Longtin J, Vermeiren C, Shahinas D, Tamber GS, McGeer A, Low DE, et al. Novel mutations in a patient isolate of Streptococcus agalactiae with reduced penicillin susceptibility emerging after long-term oral suppressive therapy. Antimicrob Agents Chemother. 2011;55:2983–5.
  12. Murdoch DR, Reller LB. Antimicrobial susceptibilities of group B streptococci isolated from patients with invasive disease: 10–year perspective. Antimicrobial agents and chemotherapy. 2001;45:3623–4.
  13. Fernandez M, Hickman ME, Baker CJ. Antimicrobial susceptibilities of group B streptococci isolated between 1992 and 1996 from patients with bacteremia or meningitis. Antimicrobial agents and chemotherapy. 1998;42:1517–9.
  14. Garland SM, Cottrill E, Markowski L, Pearce C, Clifford V, Ndisang D, et al. Antimicrobial resistance in group B streptococcus: the Australian experience. J Med Microbiol. 2011;60:230–5.
  15. DiPersio LP, DiPersio JR. High rates of erythromycin and clindamycin resistance among OBGYN isolates of group B Streptococcus. Diagn Microbiol Infect Dis. 2006;54:79–82.
  16. von Both U, Ruess M, Mueller U, Fluegge K, Sander A, Berner R. A serotype V clone is predominant among erythromycin-resistant Streptococcus agalactiae isolates in a southwestern region of Germany. Journal of clinical microbiology. 2003;41:2166–9.
  17. von Both U, Buerckstuemmer A, Fluegge K, Berner R. Heterogeneity of genotype-phenotype correlation among macrolide-resistant Streptococcus agalactiae isolates. Antimicrobial agents and chemotherapy. 2005;49:3080–2.
  18. Manning SD, Foxman B, Pierson CL, Tallman P, Baker CJ, Pearlman MD. Correlates of antibiotic-resistant group B streptococcus isolated from pregnant women. Obstet Gynecol. 2003;101:74–9.
  19. Lin FY, Azimi PH, Weisman LE, Philips JB, 3rd, Regan J, Clark P, et al. Antibiotic susceptibility profiles for group B streptococci isolated from neonates, 1995–1998. Clinical infectious diseases: an official publication of the Infectious Diseases Society of America. 2000;31:76–9.
  20. Uh Y, Kim HY, Jang IH, Hwang GY, Yoon KJ. Correlation of serotypes and genotypes of macrolide-resistant Streptococcus agalactiae. Yonsei Med J. 2005,46:480–3.
  21. EUCAST. Clinical Breakpoint Table v. 3,1. European Commitee on Antimicrobial Susceptibility Testing.
  22. Woods CR. Macrolide-inducible resistance to clindamycin and the D-test. Pediatr Infect Dis J. 2009;28:1115–8.
  23. EUCAST. Expert rules. European Commitee on Antimicrobial Susceptibility Testing
  24. Slotved HC, Elliott J, Thompson T, Konradsen HB. Latex assay for serotyping of group B Streptococcus isolates. Journal of clinical microbiology. 2003;41:4445–7.
  25. Kong F, Gowan S, Martin D, James G, Gilbert GL. Serotype identification of group B streptococci by PCR and sequencing. Journal of clinical microbiology. 2002;40:216–26.
  26. Arpin C, Daube H, Tessier F, Quentin C. Presence of mefA and mefE genes in Streptococcus agalactiae. Antimicrob Agents Chemother. 1999;43:944–6.
  27. Berkowitz K, Regan JA, Greenberg E. Antibiotic resistance patterns of group B streptococci in pregnant women. Journal of clinical microbiology. 1990;28:5–7.
  28. de Azavedo JC, McGavin M, Duncan C, Low DE, McGeer A. Prevalence and mechanisms of macrolide resistance in invasive and noninvasive group B streptococcus isolates from Ontario, Canada. Antimicrobial agents and chemotherapy. 2001;45:3504–8.
  29. Capanna F, Emonet SP, Cherkaoui A, Irion O, Schrenzel J, Martinez de Tejada B. Antibiotic resistance patterns among group B Streptococcus isolates: implications for antibiotic prophylaxis for early-onset neonatal sepsis. Swiss Med Wkly. 2013;143:w13778.
  30. Patel M, Waites KB, Moser SA, Cloud GA, Hoesley CJ. Prevalence of inducible clindamycin resistance among community- and hospital-associated Staphylococcus aureus isolates. Journal of clinical microbiology. 2006;44:2481–4.
  31. Drinkovic D, Fuller ER, Shore KP, Holland DJ, Ellis-Pegler R. Clindamycin treatment of Staphylococcus aureus expressing inducible clindamycin resistance. J Antimicrob Chemother. 2001;48:315–6.
  32. Siberry GK, Tekle T, Carroll K, Dick J. Failure of clindamycin treatment of methicillin-resistant Staphylococcus aureus expressing inducible clindamycin resistance in vitro. Clinical infectious diseases: an official publication of the Infectious Diseases Society of America. 2003;37:1257–60.
  33. Lewis JS, 2nd, Jorgensen JH. Inducible clindamycin resistance in Staphylococci: should clinicians and microbiologists be concerned? Clinical infectious diseases: an official publication of the Infectious Diseases Society of America. 2005;40:280–5.
  34. Desjardins M, Delgaty KL, Ramotar K, Seetaram C, Toye B. Prevalence and mechanisms of erythromycin resistance in group A and group B Streptococcus: implications for reporting susceptibility results. Journal of clinical microbiology. 2004;42:5620–3.
  35. Sendi P, Johansson L, Norrby-Teglund A. Invasive group B Streptococcal disease in non-pregnant adults: a review with emphasis on skin and soft-tissue infections. Infection. 2008;36:100–11.
  36. Chohan L, Hollier LM, Bishop K, Kilpatrick CC. Patterns of antibiotic resistance among group B streptococcus isolates: 2001–2004. Infectious diseases in obstetrics and gynecology. 2006;2006:57492.
  37. Wang H, Zhao CJ, He WQ, Zhang FF, Zhang LY, Cao B, et al. High Prevalence of Fluoroquinolone-Resistant Group B Streptococci among Clinical Isolates in China and Predominance of Sequence Type 19 with Serotype III. Antimicrobial Agents and Chemotherapy. 2013;57:1538–41.
  38. Back EE, O'Grady EJ, Back JD. High rates of perinatal group B Streptococcus clindamycin and erythromycin resistance in an upstate New York hospital. Antimicrob Agents Chemother. 2012;56:739–42.

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