A 5-year study of the performance of the Verigene Gram-positive blood culture panel in a pediatric hospital

Abstract

High accuracy of direct from positive blood culture molecular panels is imperative, particularly for the detection of resistance determinants as it allows for antimicrobial optimization prior to conventional susceptibility testing. In this study, we provide extensive data since implementation of the Verigene Gram-positive blood culture panel (BC-GP) in 2013. Within 5 years, 1636 blood culture bottles positive for a Gram-positive organism were tested on the BC-GP panel. The BC-GP panel identified 1520 Gram-positive organisms in 1636 (92.9%) blood cultures tested. For positive blood cultures, we observed 96.4% (806/834) concordance to the species level. Compared with conventional antimicrobial susceptibility testing, the positive percent agreement (PPA) of methicillin-resistant SA (MRSA) (50) and methicillin-resistant SE (MRSE) (365) was 100%. The mecA gene was detected in two methicillin-susceptible Staphylococcus aureus (MSSA) and one methicillin-susceptible S. epidermidis (MSSE) with a negative percent agreement (NPA) of 99.1% (221/223) and 99.2% (120/121), respectively. The PPA and NPA for vancomycin-resistant Enterococcus faecium (VRE) was 100%. The BC-GP panel demonstrated excellent performance and clinicians can confidently de-escalate antimicrobial therapy in the absence of mecA and vanA/B gene.