For isolation and differentiation of Streptococcus agalactiae (GBS)

Group B Streptococcus (GBS) has been associated with severe neonatal infections such as septicaemia and meningitis. The detection of vaginal colonisation by GBS in pregnant women is the most effective strategy to prevent neonatal infections. CHROMagar StrpB is a powerful screening tool, sensitive and highly specific, allowing detection of GBS (haemolytic as well as non-haemolytic) after only 18-24h of aerobic incubation.

Typical appearance of microrganisms

Group B Streptococcus → mauve
Other Microrganism → colourless, blue or inhibited

CHROMagar, AquaCHROM, and RambaQUICK are trademarks of Dr A. Rambach

Medium Description

Storage at 15/30°C - pH 7.3 +/- 0.2

Supplements Description (included)

Storage at 15/30°C

Storage at 2/8°C

Procedure

Direct Streaking

Possible Prior Todd Hewitt/LIM enrichment

Incubation 18-24h at 37ºC

Aerobic conditions

Easy Interpretation: Easier reading thanks to an intense mauve colony colouration

High Sensitivity: Detection of GBS, including non-haemolytic strains, with sensitivity close to 100%

High Specificity: Differentiation of GBS frim other bacteria by selective inhibition or by counter-colouration

Fast: Results in 18-24h

Simplicity: Incubation in aerobic conditions. No need of CO₂. Confirmation by latex agglutination can be performed diretcly from the colony

Comparison of CHROMagar StrepB, Columbia CNA agar and Lim broth for the isolation of Group B Streptococcus from vaginal and rectal swabs from South Africa (2012) Publication

Evaluation of CHROMagar™ StrepB agar, an aerobic chromogenic medium for prepartum vaginal/rectal Group B Streptococcus screening (2011) Publication

Rapid Detection with culture media of Streptococcus agalactiae in genital samples on a new chromogenic media CHROMagar StrepB (2010) Publication

Comparison of the Rate of Recovery of Group B Streptococci from Genital Specimens Inoculated into Group B Selective Broth and Sub-cultured to Neomycin Nalidixic Acid Plates and Three Different Chromogenic Media (2010) Publication

Group B Streptococcus Detection by Carrot Broth/CHROMagar Colorex GBS Agar vs. Conventional Colistin/Nalidixic Acid Agar/Group B Strep Broth Method (2010) Publication

Evaluation of CHROMagar™ StrepB: A new chromogenic agar medium for aerobic detection of Group B Streptococci in perinatal samples (2010) Publication

Perpartum anti Group B Streptococcus Antibioprophylaxis: What would be the impact of the CDC’s Guidelines in a French Hospital? (2010) Publication

Perpartum antibioprophylaxis: comparison of Group B Streptococcus detection rates of two chromogenic media and blood agar for its isolation in pregnant women vaginal swabs (2010) Publication