TABLE 6.

ESBL results for the E. coli and Klebsiella isolates tested in this study

Isolate type and speciesNo. of resultsa:Result (%) forb:
Total+ by both testsPHX+ and REF−PHX− and REF+− by both testsSensitivitySpecificityPPVNPVAgreement
Clinical
    E. coli7160065100100100100100
    K. pneumoniae4970042100100100100100
    K. oxytoca275102110095.583.310096.3
Challenge
    E. coli3112111792.394.492.394.493.5
    K. pneumoniae2017003100100100100100
    K. oxytoca53002100100100100100
Clinical and challenge
    E. coli10218118294.798.894.798.898.0
    K. pneumoniae69240045100100100100100
    K. oxytoca328102310095.888.910096.9
Total203502115098.098.796.299.398.5
  • a PHX, Phoenix system; REF, reference method. +, positive; −, negative.

  • b PPV, positive predictive value; NPV, negative predictive value.