Rapid Detection of Pathogens and Resistance Genes Grown in Blood Cultures with Two Multiplex Tandem Real-Time PCR...

In this study, two multiplex tandem real-time PCR kits were used to rapidly diagnose common Gram-positive cocci and Gram-negative bacilli, detect their commonly seen antibiotic resistance genes, and evaluate the two kits' performance.

Gram-positive 12 (GP-12) kit (AusDiagnostics, Australia) and Gram-negative 12 (GN-12) kit (AusDiagnostics, Australia) were used in the study. Seventy-eight Gram-negative bacilli and 54 Gram-positive cocci grown in blood culture vials were applied to GN-12 and GP-12 panels. At the same time, the passages of the samples were made and incubated. After that, identification and antibiograms were made in the Phoenix™ automated system (Becton, Dickinson and Company, USA) and VITEK 2 Compact automated system (bioMérieux, France).

Twenty-one Staphylococcus aureus, twelve coagulase-negative staphylococci (CoNS), two Streptococcus pneumoniae, two Enterococcus faecium, and three Enterococcus faecalis were found to match the results from the automated GP-12 Kit. Pathogens present in the panel were successfully identified using the GN-12 kit. Both panels were found to be more effective in diagnosing polymicrobial infections.

These evaluated kits were rapid (approximately three hours) and valuable in identifying common sepsis pathogens and resistance genes. Thus, these tests can easily be used in the diagnosis of sepsis.