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Abstract Purpose Group B Streptococcus (GBS) is the leading cause of invasive infections in newborns. The prevention of GBS neonatal disease relies on the administration of an intrapartum antibiotic prophylaxis to GBS-colonized women. In recent years, rapid intrapartum detection of GBS vaginal colonization using real-time nucleic acid amplification tests (NAATs) emerged as an alternative to antenatal culture screening methods. Methods We compared the performances of two loop-mediated isothermal amplification (LAMP) tests, the Ampliflash® GBS and the PlusLife® GBS tests, to standard culture for GBS detection in vaginal specimens from pregnant women. The study was conducted from April to July 2023 in a French hospital of the Paris area. Results A total of 303 samples were analyzed, including 85 culture-positive samples (28.1%). The Ampliflash® GBS test and the PlusLife® GBS tests gave a result for 100% and 96.3% tests, respectively. The performances of the tests were as follows: sensitivity 87.1% (95% confidence interval (CI) 78.3–92.6) and 98.7% (95% CI 93.0-99.8), specificity 99.1% (95% CI 96.7–99.8), and 91.9% (95% CI 87.3–95.0), respectively. False negative results of the Ampliflash® GBS test correlated with low-density GBS cultures. Time-to-results correlated with GBS culture density only for the PlusLife® GBS test (p

Purpose: Group B Streptococcus (GBS) is the leading cause of invasive infections in newborns. The prevention of GBS neonatal disease relies on the administration of an intrapartum antibiotic prophylaxis to GBS-colonized women. In recent years, rapid intrapartum detection of GBS vaginal colonization using real-time nucleic acid amplification tests (NAATs) emerged as an alternative to antenatal culture screening methods. Methods: We compared the performances of two loop-mediated isothermal amplification (LAMP) tests, the Ampliflash® GBS and the PlusLife® GBS tests, to standard culture for GBS detection in vaginal specimens from pregnant women. The study was conducted from April to July 2023 in a French hospital of the Paris area. Results: A total of 303 samples were analyzed, including 85 culture-positive samples (28.1%). The Ampliflash® GBS test and the PlusLife® GBS tests gave a result for 100% and 96.3% tests, respectively. The performances of the tests were as follows: sensitivity 87.1% (95% confidence interval (CI) 78.3–92.6) and 98.7% (95% CI 93.0-99.8), specificity 99.1% (95% CI 96.7–99.8), and 91.9% (95% CI 87.3–95.0), respectively. False negative results of the Ampliflash® GBS test correlated with low-density GBS cultures. Time-to-results correlated with GBS culture density only for the PlusLife® GBS test (p < 0.001). Conclusion: Both techniques provide excellent analytical performances with high sensitivity and specificity together with a short turnaround time and results available in 10 to 35 min. Their potential to further reduce the burden of GBS neonatal disease compared with antenatal culture screening needs to be assessed in future clinical studies. [ABSTRACT FROM AUTHOR]

Abstract Background Streptococcus agalactiae or group B Streptococcus (GBS) is a leading infectious cause of neonatal morbidity and mortality. It is essential to establish a robust method for the rapid and ultra-sensitive detection of GBS in pregnant women with premature rupture of membrane (PROM). Methods This study developed a CRISPR-GBS assay that combined the advantages of the recombinase polymerase amplification (RPA) and CRISPR/Cas12a system for GBS detection. The clinical performance of the CRISPR-GBS assay was assessed using vaginal or cervical swabs that were collected from 179 pregnant women with PROM, compared in parallel to culture-based matrix-assisted laser desorption ionization time-of-flight mass spectrometry (culture-MS) method and real-time quantitative polymerase chain reaction (qPCR) assay. Results The CRISPR-GBS assay can be completed within 35 min and the limit of detection was as low as 5 copies μL−1. Compared with the culture-MS, the CRISPR-GBS assay demonstrated a sensitivity of 96.64% (144/149, 95% confidence interval [CI] 92.39–98.56%) and a specificity of 100% (30/30, 95% CI 88.65–100%). It also had a high concordance rate of 98.88% with the qPCR assay. Conclusions The established CRISPR-GBS platform can detect GBS in a rapid, accurate, easy-to-operate, and cost-efficient manner. It offered a promising tool for the intrapartum screening of GBS colonization.

Background: Streptococcus agalactiae or group B Streptococcus (GBS) is a leading infectious cause of neonatal morbidity and mortality. It is essential to establish a robust method for the rapid and ultra-sensitive detection of GBS in pregnant women with premature rupture of membrane (PROM). Methods: This study developed a CRISPR-GBS assay that combined the advantages of the recombinase polymerase amplification (RPA) and CRISPR/Cas12a system for GBS detection. The clinical performance of the CRISPR-GBS assay was assessed using vaginal or cervical swabs that were collected from 179 pregnant women with PROM, compared in parallel to culture-based matrix-assisted laser desorption ionization time-of-flight mass spectrometry (culture-MS) method and real-time quantitative polymerase chain reaction (qPCR) assay. Results: The CRISPR-GBS assay can be completed within 35 min and the limit of detection was as low as 5 copies μL−1. Compared with the culture-MS, the CRISPR-GBS assay demonstrated a sensitivity of 96.64% (144/149, 95% confidence interval [CI] 92.39–98.56%) and a specificity of 100% (30/30, 95% CI 88.65–100%). It also had a high concordance rate of 98.88% with the qPCR assay. Conclusions: The established CRISPR-GBS platform can detect GBS in a rapid, accurate, easy-to-operate, and cost-efficient manner. It offered a promising tool for the intrapartum screening of GBS colonization. [ABSTRACT FROM AUTHOR]

Objectives: To estimate the prevalence of group B streptococcus at onset of labor and to compare the accuracy of intrapartum antibiotic prophylaxis based on a risk factor strategy versus an intrapartum screening.Study Design: In this cross-sectional study, 700 women referred for intended vaginal delivery were tested for group B streptococcus at onset of labor by gold standard culture in vaginal and rectal swabs. The results were blinded, and intrapartum antibiotic prophylaxis was given to women with risk factors for group B streptococcus infection: previous neonatal group B streptococcus infection, group B streptococcus in urine and/or vagina in current pregnancy, gestational age <36 + 0 weeks, temperature ≥38.0 °C or rupture of membranes ≥18 h.Results: Of 642 women, who delivered within three days of specimen collection, 170 (26.5%) received benzylpenicillin as intrapartum antibiotic prophylaxis based on risk factors. The prevalence of group B streptococcus at onset of labor was 17.8% (114/642), with 62 women positive for group B streptococcus in both the vagina and rectum, 12 in the vagina only and 40 in rectum only. Intrapartum antibiotic prophylaxis was administered correctly in 31.6% (36/114) of GBS positive women at time of delivery and 78.8% (134/170) of women who received antibiotics were actually GBS negative. The positive predictive value of intrapartum antibiotic prophylaxis based on risk factors was 21.2%. The sensitivity was 31.6% and the specificity was 74.6%.Conclusion: The accuracy of predicting maternal group B streptococcus infection from risk factors is low. Intrapartum group B streptococcus diagnostics is more precise and will not increase the overall use of intrapartum antibiotic prophylaxis. [ABSTRACT FROM AUTHOR]

Objective: To evaluate group B streptococcus (GBS) colonization prevalence and feasibility of intrapartum GBS screening/antibiotic prophylaxis (IAP) in Cameroon, Africa.Methods: Prospective cohort in the Cameroon Baptist Convention Health Services network. Maternity providers collected anogenital swabs from consenting term women in labor for testing by a rapid GBS-polymerase chain reaction (PCR) system. Positive tests (GBS+) resulted in initiation of intravenous ampicillin until delivery. Primary outcomes were GBS prevalence and proportion of GBS+ women receiving ampicillin before delivery and more than 4 hours before delivery.Results: A total of 219 women were enrolled from January 10 to April 27, 2017. GBS prevalence was 12.3% (95% confidence interval [CI] 7.9-16.7) with GBS+ women more likely to reside in urban areas (19.6% vs 9.7%, P=0.004). Of 27 GBS+ women, 19 (70.4%) received ampicillin before delivery and 14 (51.9%) 4 hours or longer before delivery. A median two doses of ampicillin (interquartile range [IQR] 1-5) were given and started at a median of 105 minutes (IQR 90-155) after swab collection and 20 minutes (IQR 10-45) after GBS result. Of the 8 women who did not receive ampicillin, 7 (87.5%) delivered before test results.Conclusion: A GBS IAP protocol is feasible in Cameroon and should be evaluated for widespread implementation in Cameroon and other low-income countries to decrease GBS-related morbidity. [ABSTRACT FROM AUTHOR]

Objective: The objective of this study was to analyze the diagnostic accuracy of a commercial real-time polymerase chain reaction (PCR) assay for group B streptococcus (GBS) colonization status and to compare results of the intrapartum PCR with the antepartum conventional GBS culture in Japanese pregnant women.Methods: This prospective observational study enrolled Japanese pregnant women at 35-37 weeks' gestation. Paired recto-vaginal swabs were obtained for PCR and conventional culture, both at 35-37 weeks' gestation and at admission for delivery. Performance of PCR was analyzed by comparing with the culture results. Furthermore, using the intrapartum culture results as the gold standard, the test of both the antepartum culture and the intrapartum PCR were characterized.Results: We prospectively enrolled 79 pregnant women at 35-37 weeks' gestation, and the intrapartum results were obtained from 73 of those women. The sensitivity of PCR was 86.2%, and concordance rate with the conventional culture was 96.7% overall. Compared with the intrapartum culture, the sensitivity and the specificity of the intrapartum PCR were 83.3% and 98.4%, respectively, while the sensitivity and the specificity of the antepartum culture were 100.0% and 95.1%.Conclusions: The intrapartum real-time PCR assay for GBS screening has the accuracy similar to the antepartum conventional culture method. [ABSTRACT FROM AUTHOR]

Prevention of perinatal Group B Streptococcus (GBS) transmission is crucial in our effort to prevent Early-onset GBS disease. Here, we established the performance of the Revogene GBS DS assay for the detection of group B streptococcus on intrapartum vaginal samples in a laboratory environment using a prospective noninterventional study design. Intrapartum vaginal swabs were enriched using a selective culture method which served as study reference method. Overall, 119 patients were enrolled with an antenatal and intrapartum Group B Streptococcus colonization prevalence of 12.9% and 11.8%, respectively. Compared to intrapartum culture, the Revogene GBS DS assay had a sensitivity of 92.9% and a specificity of 99.1%, while the antenatal culture displayed a sensitivity 78.6% of and specificity of 96.2%. The Revogene GBS DS assay displayed an acceptable performance according to the European Group B Streptococcus consensus recommendations. Complementary studies in clinical practice are needed to confirm these findings. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the positive predictive value (PPV) of group B Streptococcus (GBS) cultures at 35-37 weeks of gestation relative to GBS colonization status at delivery. Methods: Rectovaginal swabs from 221 women at labor in four Lisbon hospitals were collected for GBS screening according to the CDC guidelines. Results: The PPV was 24.4%. IAP was administered to 100% of prenatally GBS positive women. There was no case of early onset GBS disease (EOD). Conclusions: Poor accuracy of prenatal cultures in identifying true candidates for IAP highlights the need for Portuguese clinical and laboratory guidelines to prevent EOD and antibiotic overtreatment of pregnant women. [ABSTRACT FROM AUTHOR]

Objective: We sought to evaluate an intrapartum nucleic acid amplification test (NAAT) for group B streptococcus (GBS). Study Design: This was a prospective cohort study of 559 women comparing intrapartum GBS culture with antepartum culture and intrapartum NAAT. Results: GBS prevalence was 19.5% by antepartum culture and 23.8% by intrapartum culture. Compared with intrapartum culture, antepartum culture had 69.2% sensitivity (60.6-76.9%) and 96.0% specificity (93.7-97.7%). The NAAT demonstrated sensitivity of 90.8% (84.6-95.2%), specificity of 97.6% (95.6-98.8%), and predictive values >92%. The incidence of discordant cultures was 10.4%. Of the women with negative antepartum and positive intrapartum cultures, only 1 (2.4%) received intrapartum antibiotics. Compared with white women, black (P = .02) and Hispanic (P = .02) women were more likely to have discordant cultures. Conclusion: This intrapartum NAAT has excellent characteristics. It may be superior to antepartum culture for detecting intrapartum GBS–allowing more accurate management of laboring mothers and reducing neonatal GBS sepsis. [ABSTRACT FROM AUTHOR]

Objective: We sought to evaluate whether group B streptococcus (GBS) detection is altered by the digital cervical examination. Study Design: A total of 302 women undergoing the clinical GBS culture had a digital cervical examination and a repeated GBS culture. Statistical comparison of pre–post culture results were performed with kappa and McNemar tests. Results: The clinical prevalence of GBS was 19.5%. Discordant results were seen in 30/302 (9.9%) paired cultures (κ = 0.68; 95% confidence interval, 0.568–0.783). An initially negative GBS culture result was positive on repeated testing in 13/243 (5.3%) pairs. Initially positive cultures were negative on repeated testing in 17/59 (28.8%) pairs. Patients with discordant results had similar characteristics as the remainder of the study group. Given the observed proportion of discordant results (9.9%), the study had 80% power to detect a 5% difference between discordant pairs. Conclusion: Paired GBS cultures showed a good level of agreement. The 28.8% rate of positive cultures becoming negative is clinically concerning and warrants further study. [Copyright &y& Elsevier]