Culture-based methods for detection and identification of Streptococcus agalactiae in pregnant women—what are we missing?

  • A. AdlerEmail author
  • C. Block
  • D. Engelstein
  • D. Hochner-Celnikcier
  • R. Drai-Hassid
  • A. E. Moses
Brief Report


We aimed to compare BD group B Streptococcus differential agar (GBSDA) with inoculation into LIM broth and subculture onto blood agar plates (LIM-BA) as a method for GBS screening in pregnant women. First, we compared the detection threshold and the ease of use of GBSDA with LIM-BA by inoculating known numbers of GBS mixed with approximately 105 cfu of other bacteria. Second, we tested the production of carotenoid pigment in 155 GBS blood culture isolates. Finally, we compared GBSDA, LIM broth with direct GBS antigen detection (LIM-AG) and LIM-BA as methods for GBS screening in pregnant women. GBS colonies were easily detected on GBSDA at a threshold of 20 cfu. In contrast, GBS was not detected in a mixed culture from LIM broth with initial inocula of up to 100 cfu. Orange pigment was produced in 146/155 GBS blood culture isolates. Pigment was not produced in eight non-hemolytic and two hemolytic strains. GBS was detected by GBSDA in 58 out of 297 parturient women (19.5%) but in only 50 (16.8%, P > 0.05) and 46 (15.4%, P = 0.079) women by LIM-BA and LIM-AG, respectively. GBSDA is a satisfactory medium for the rapid detection of most GBS isolates, but other methods may be needed if detection of all non-pigmented strains is required.


Carotenoid Pigment Vaginal Swab Streptococcus Agalactiae Blood Culture Isolate Parturient Woman 
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The study was supported by a grant from the Israeli Women Health Fund.


  1. 1.
    Centers for Disease Control and Prevention (2002) Prevention of perinatal group B streptococcal disease. MMWR 51:1–22Google Scholar
  2. 2.
    De La Rosa M, Perez M, Carazo C, Pareja L, Pies JI, Hernandez F (1992) New Granada Medium for detection and identification of group B streptococci. J Clin Microbiol 30:1019–1021PubMedGoogle Scholar
  3. 3.
    Votava M, Tejkalová M, Drábková M, Unzeitig V, Braveny I (2001) Use of GBS media for rapid detection of group B streptococci in vaginal and rectal swabs from women in labor. Eur J Clin Microbiol Infect Dis 20:120–122PubMedCrossRefGoogle Scholar
  4. 4.
    Overman SB, Eley DD, Jacobs BE, Ribes JA (2002) Evaluation of methods to increase the sensitivity and timeliness of detection of Streptococcus agalactiae in pregnant women. J Clin Microbiol 40:4329–4331PubMedCrossRefGoogle Scholar
  5. 5.
    Gupta C, Briski LE (2004) Comparison of two culture media and three sampling techniques for sensitive and rapid screening of vaginal colonization by group B Streptococcus in pregnant women. J Clin Microbiol 42:3975–3977PubMedCrossRefGoogle Scholar
  6. 6.
    Bou C, Figueira M, Canle D, Cartelle M, Eiros JM, Villanueva R (2005) Evaluation of group B Streptococcus differential agar for detection and isolation of Streptococcus agalactiae. Clin Microbiol Infect 11:676–678PubMedCrossRefGoogle Scholar
  7. 7.
    Rallu F, Barriga P, Scrivo C, Martel-Laferriére V, Laferrière C (2006) Sensitivities of antigen detection and PCR assays greatly increased compared to that of the standard culture method for screening for group B Streptococcus carriage in pregnant women. J Clin Microbiol 44:725–728PubMedCrossRefGoogle Scholar
  8. 8.
    Eisenberg VH, Raveh D, Meislish Y, Rudensky B, Ezra Y, Samueloff A, Eidelman AI, Schimmel MS (2006) Prevention of early-onset neonatal group B streptococcal infection: is universal screening by culture universally applicable? Isr Med Assoc J 8:698–702PubMedGoogle Scholar
  9. 9.
    Merritt K, and Jacobs NJ (1978) Characterization and incidence of pigment production by human clinical group B streptococci. J Clin Microbiol 8:105–107PubMedGoogle Scholar
  10. 10.
    Liu GY, Doran KS, Lawrence T, Turkson N, Puliti M, Tissi L, Nizet V (2004) Sword and shield: linked group B streptococcal beta-hemolysin/cytolysin and carotenoid pigment function to subvert host phagocyte defense. Proc Natl Acad Sci USA 101:14491–14496PubMedCrossRefGoogle Scholar
  11. 11.
    Puopolo KM, Madoff LC, Eichenwald EC (2005) Early-onset group B streptococcal disease in the era of maternal screening. Pediatrics 115:1240–1246PubMedCrossRefGoogle Scholar

Copyright information

© Springer-Verlag 2007

Authors and Affiliations

  • A. Adler
    • 1
    Email author
  • C. Block
    • 1
  • D. Engelstein
    • 1
  • D. Hochner-Celnikcier
    • 2
  • R. Drai-Hassid
    • 2
  • A. E. Moses
    • 1
  1. 1.Departments of Clinical Microbiology and Infectious DiseasesHadassah-Hebrew University Medical CentreJerusalemIsrael
  2. 2.Obstetrics and Gynecology (Mt. Scopus Campus)Hadassah-Hebrew University Medical CentreJerusalemIsrael

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