Identification of Escherichia coli, Klebsiella pneumoniae, and Pseudomonas aeruginosa in blood cultures: a multicenter performance evaluation of a three-color peptide nucleic acid fluorescence in situ hybridization assay.

A multicenter evaluation was undertaken to evaluate the performance of a new three-color peptide nucleic acid fluorescence in situ hybridization assay that identifies isolates directly from blood cultures positive for Gram-negative bacilli (GNB). The assay correctly identified 100% (186/186) of the Escherichia coli isolates, 99.1% (109/110) of the Klebsiella pneumoniae isolates, and 95.

Multicenter evaluation of a new shortened peptide nucleic acid fluorescence in situ hybridization procedure for species identification of select Gram-negative bacilli from blood cultures.

A shortened protocol for two peptide nucleic acid fluorescence in situ hybridization (PNA FISH) assays for the detection of Gram-negative bacilli from positive blood cultures was evaluated in a multicenter trial. There was 100% concordance between the two protocols for each assay (368 of 368 and 370 of 370 results) and 99.7% (367 of 368 and 369 of 370 results) agreement with routine laboratory techniques.