Phenotypic and Molecular Characterization of Plasmid Mediated AmpC β-Lactamases among Escherichia coli, Klebsiella spp., and Proteus mirabilis Isolated from Urinary Tract Infections in Egyptian Hospitals

Table 3

Comparison of sensitivities, specificities, and predictive values of phenotypic tests for detection of AmpC-positive isolates.

	Cloxacillin test	AmpC disc test	Phenylboronic acid
Sensitivity	78.3%	78.3%	65.2%
Specificity	100%	100%	73.9%
PPV*	100%	100%	94.4%
NPV^†	37.5	37.5	20%

Notes:∗indicates positive predictive value.
^†indicates negative predictive value.