Evaluation of the BD Phoenix Carbapenemase-Producing Organism Panels for the Detection of Carbapenemase Producers in Escherichia coli, Klebsiella pneumoniae and Pseudomonas aeruginosa.

ABSTRACT

The classification of carbapenemases can help guide therapy. The present study evaluated the performance of the CPO detection test, included in the BD Phoenix™ NMIC-501 panel for the detection and classification of carbapenemases on the representative molecularly characterized strains collection from Mexico. Carbapenem non-susceptible isolates collected in Mexico were included. The clinical isolates (n = 484) comprised Klebsiella pneumoniae (n = 154), Escherichia coli (n = 150), and P. aeruginosa (n = 180). BD Phoenix CPO NMIC-504 and NMIC-501 panels were used for the identification of species, antimicrobial susceptibility tests, and detection of CPOs. For the detection of carbapenemase-encoding genes, E. coli and K. pneumoniae were evaluated using PCR assays for blaNDM-1, blaKPC, blaVIM, blaIMP, and blaOXA-48-like. For P. aeruginosa, blaVIM, blaIMP, and blaGES were detected using PCR. Regarding E. coli, the CPO panels had a sensitivity of 70% and specificity of 83.33% for the detection of a class B carbapenemase (blaNDM in the molecular test). Regarding K. pneumoniae, the panels had a sensitivity of 75% and specificity of 100% for the detection of a class A carbapenemase (blaKPC in the molecular test). The Phoenix NMIC-501 panels are reliable for detecting class B carbapenemases in E. coli. The carbapenemase classification in K. pneumoniae for class A carbapenemases has a high specificity and PPV; thus, a positive result is of high value.