Patent ID: 8097434

Claim:
A method for detecting the presence of a beta-lactamase, comprising: (a) contacting: a first bacterial sample with a first composition comprising a detectable beta-lactamase substrate and an AmpC inhibitor, and ii. a second bacterial sample with a second composition comprising a detectable beta-lactamase substrate, an AmpC inhibitor, and a serine beta-lactamase inhibitor in an amount sufficient to inhibit an extended-spectrum beta-lactamase (ESBL) and an original-spectrum beta-lactamase (OSBL) but not a class A serine carbapenemase, wherein the first and second bacterial samples are from the same source; and (b) detecting substrate utilization in the first composition and the second composition, such that a beta-lactamase is detected if the substrate has been utilized in the first and second compositions, wherein the beta-lactamase is a class A serine carbapenemase or a metallo-beta-lactamase.