Multicenter Evaluation of NeuMoDx Group B Streptococcus Assay on the NeuMoDx 288 Molecular System

Group B Streptococcus (GBS) is the leading cause of neonatal sepsis and meningitis in developed countries. Recommendations for antepartum GBS detection include enriched culture with several options for identifying GBS, some of which are time-consuming. To reduce the time for identification and determination of the maternal GBS colonization status, rapid nucleic acid amplification technologies have been developed and commercialized. For rapid detection of GBS, a three-site clinical study was conducted to evaluate the NeuMoDx GBS assay, a real-time PCR test performed for vaginal/rectal swab specimens in Lim broth enrichment culture on the NeuMoDx 288 molecular system (NeuMoDx system); these data were used to a support 510(k) submission. A total of 1,250 eligible remnant samples were prospectively enrolled and tested during the study. The results of the PCR assay were compared to the results of the Centers for Disease Control and Prevention (CDC)-recommended enriched-culture method, which served as the gold standard reference method for the study. The NeuMoDx GBS assay results yielded a sensitivity of 96.9% (95% confidence interval [CI] = 94.1 to 98.4), specificity of 96.0% (95% CI = 94.6 to 97.1), and a total agreement with the reference method of 96.2% (95% CI = 93.8 to 98.3). NeuMoDx GBS assay results were also compared to results obtained using the BD MAX GBS assay on the BD MAX system. The two systems demonstrated a total percent agreement of 98.0% (95% CI = 95.5 to 100.0). The performance of the NeuMoDx GBS assay implemented on the NeuMoDx system compared favorably to the CDC enriched-culture method and to the BD MAX GBS assay.