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Purpose: Streptococcus agalactiae remains a major pathogen in human health, especially in neonatal infection. Detection in pregnant women is essential to initiate intrapartum antibiotic prophylaxis. This study compared the HiberGene loop-mediated isothermal amplification (LAMP) assay to culture, the reference method, for the detection of group B Streptococcus (GBS) in pregnant women. Methods: This was a prospective multicenter study conducted in four French hospitals. Three hundred fifty-four non-redundant routine care vaginal swabs were analyzed by both methods, LAMP assay and culture. Clinicians and patients were blinded to the results of the LAMP assay. Results: Three hundred thirty-seven samples presented concordant results, 15 presented discordant results, and 2 were invalid using the LAMP assay (excluded from the study). Compared to culture, the LAMP assay had a sensitivity of 87.7%, a specificity of 98%, a negative predictive value of 97.6%, and a positive predictive value of 89.3%. Conclusion: The HiberGene GBS LAMP assay is an easy test that possesses good performances compared with the reference method, culture. It could be used in case of emergency when a quick result is needed. [ABSTRACT FROM AUTHOR]

A recently developed, automated blood culture system and medium improve the time-to-positivity (TTP) for bacteremia. However, there have thus far been no genus-level analyses using this novel system. We evaluated and compared the changes in blood culture TTP between two systems: BacT/Alert 3D with a blood culture medium containing activated charcoal versus the more recent BacT/Alert Virtuo with a blood culture medium containing polymeric beads. This before-and-after study included blood cultures collected between July 2010 and April 2014 (3D, activated charcoal) and between July 2015 and April 2018 (Virtuo, polymeric beads). A total of 554,732 blood cultures were included, 267,935 (48.30%) during the first period and 286,797 (51.70%) during the second period. Overall, 55,611 (10.02%) tested positive for at least one microorganism. The incubation of the blood culture medium in the Virtuo system was associated with reduced TTP for the most prevalent bacteria, those representing 91.72% (n=51,006) of all the positive blood cultures. The median TTP was reduced by 0.99 h for Staphylococcus, Enterococcus, Streptococcus, Pseudomonadales, and most of the genera within the order Enterobacterales (except the family Morganellaceae). However, strictly anaerobic bacteria belonging to the genus Bacteroides, representing 0.85% (n=474) of all positive blood cultures, were detected 4.53 h later using the Virtuo system. Virtuo was associated with a shorter TTP for most bacteria, but this improvement was heterogeneous to the genus level. [ABSTRACT FROM AUTHOR]