Fig 1.
A positive test was interpreted as the development of yellow, orange or a lighter shade of red than the negative control.
Tests with the positive control isolate, KPC-producing K. pneumoniae BAA 1705 and the negative control isolate K. aerogenes G1614 are shown.
Table 1.
Guide to Interpretation of carbapenemase classification tests.
Fig 2.
Classification test for Class A CPO, KPC-producing K. pneumoniae BAA 1705 after 10 minutes incubation.
Tubes A and C are positive (yellow). Tube B is negative (red). Tube A contains only the test solution and indicates that the isolate is carbapenemase-positive. Tubes B and C contain the test solution plus inhibitors of Class A and B carbapenemases respectively.
Fig 3.
Classification test for Class B CPO, NDM-5-producing E. coli CDC 0150 after 1 minute incubation showing positive results in tubes A and B and a negative result in tube C.
Fig 4.
Classification test for Class D CPO, OXA-23-producing A. baumannii G1703 after 30 minutes incubation showing positive results in all three tubes.
Table 2.
CPO detection and classification test results.