Molecular detection of antibiotic resistance genes from positive blood cultures

Rapid detection of the bacterial causative agent causing sepsis must be coupled with rapid identification of the antibiotic resistant mechanism that the pathogen might possess. Real-time PCR (qPCR)-based assays have been extensively utilized in the clinical microbiology field as diagnostic tools for the rapid detection of specific nucleic acid (NA) targets. In this chapter, we will discuss the technical aspects of using an internally controlled qPCR assay for the rapid detection of Klebsiella pneumoniae carbapenemase gene (bla KPC) in positive Bactec blood culture bottles. The multiplex qPCR (bla KPC/RNase P) utilizes specific primers and probes for the detection of the bacterial carbapenem resistance mechanism, bla KPC gene, and the internal control RNase P. The internal control of the qPCR assay is vital for detecting any inhibitors that are well known to be present in the blood culture bottles. Rapid detection of the antibiotic resistant mechanism present in the bacterial pathogen causing sepsis can help in better managing patients' infection.