J Clin Microbiol
Streptococcus agalactiae, or Group B Streptococcus (GBS) is the cause of early and late-onset GBS disease in neonates and can present as septicemia, meningitis, and pneumonia. Our objective was to compare the performance of two FDA-approved nucleic acid amplification tests (NAATs), the Panther Fusion and BD MAX™ systems, for detection of group B Streptococcus (GBS) in vaginal-rectal screening specimens. A total of 510 vaginal-rectal prepartum specimens were tested simultaneously in both NAATs following broth enrichment. Assay agreement was calculated using the kappa statistics. Overall agreement between assays was 99.0% (505/510; 95% CI: 0.951 to 0.997; kappa = 0.974). Discordant results were re-tested with both assays and by standard culture. The assays were also compared for workflow characteristics, including time to first results (TFR), total turnaround time (TAT), number of return visits to load additional specimens, and hands-on time (HoT).Using a standard run size of 60 specimens/day, the Panther Fusion assay had a longer time to TFR (2.4 vs. 2.0 hours), but showed a shorter overall TAT for all 60 samples (3.98 vs. 7.18 hours) due to an increased initial sample loading capacity, required less labor (35.0 vs. 71.3 sec/sample) and fewer return visits for loading additional specimens (0 vs. 2). The Panther Fusion system also had a larger sample loading capacity (120 vs. 24 samples) and greater 8-hour throughput (335 vs. 96 samples). In summary, the Panther Fusion GBS assay has comparable clinical performance to the BD MAX GBS assay, but provides a faster TAT, less HoT, and higher throughput.
School of Medicine
Pathology and Laboratory Medicine