The accuracy of extended-spectrum beta-lactamase detection in Escherichia coli and Klebsiella pneumoniae in South African laboratories using the Vitek 2 Gram-negative susceptibility card AST-N255.

Using a composite reference standard of the phenotypic and genotypic methods employed in this study, no Vitek-categorised ESBL E. coli or K. pneumoniae was found to be a non-ESBL with the exception of possible misinterpretation with K. pneumoniae SHV-hyper-producing isolates.