Efficient Direct Extended-Spectrum β-Lactamase Detection by Multiplex Real-Time PCR: Accurate Assignment of Phenotype by Use of a Limited Set of Genetic Markers

The number and diversity of genes potentially complicate genetic approaches to the rapid detection of transmissible extended-spectrum beta-lactamase genes. We developed a robust multiplexed real-time PCR assay based on targets identified in a prior survey and used this to detect relevant genes in 617 consecutive clinical isolates of extended-spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae.