title: Comparison of culture and 2 real-time polymerase chain reaction assays to detect group B Streptococcus during antepartum screening.
abstract: Group B Streptococcus (GBS) is the most common cause of life-threatening infection in neonates but is preventable if the mother is diagnosed before and treated at delivery. Using 200 vaginal-rectal swabs inoculated to enrichment (LIM) broths, we compared routine culture and 2 real-time polymerase chain reaction (PCR) assays for detection of GBS: the LightCycler (LC) Strep B analyte-specific reagents (ASRs) (Roche Diagnostics, Indianapolis, IN) and the BD GeneOhm StrepB (BD-StrepB) test (BD GeneOhm Sciences, San Diego, CA). Culture detected 26.5% GBS-positive specimens, whereas the LC Strep B ASR and BD-StrepB test identified 29.5% and 30.0% positive specimens, respectively. Because of the increased detection rate of 3.0% to 3.5% observed with PCR, a second GBS-specific amplicon was sequenced to confirm the presence of GBS that was not detected by culture. In our hands, the sensitivity/specificity of the LC Strep B ASR was 100%/95.9%, and the BD-StrepB test was 92.5%/92.5% using culture as the gold standard.
authors.affiliation: Department of Pathology and Laboratory Medicine, University of North Carolina Hospitals, Chapel Hill, NC 27599, USA.
authors.forename: Jennifer S
authors.initials: JS
authors.lastname: Goodrich
authors.forename: Melissa B
authors.initials: MB
authors.lastname: Miller
mesh_terms: D002353:Carrier State / Q000175:diagnosis; D005260:Female; D006801:Humans; D008828:Microbiological Techniques / Q000379:methods; D016133:Polymerase Chain Reaction / Q000379:methods*; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious / Q000175:diagnosis; D011296:Prenatal Diagnosis / Q000379:methods*; D012007:Rectum / Q000382:microbiology; D012680:Sensitivity and Specificity; D013290:Streptococcal Infections / Q000175:diagnosis; D013292:Streptococcus agalactiae / Q000235:genetics* / Q000302:isolation & purification*; D014621:Vagina / Q000382:microbiology