EVALUATION OF FOUR PHENOTYPIC TESTS FOR THE DETECTION OF OXA-48-TYPE CARBAPENEMASE IN ENTEROBACTERIACEAE

Abstract

Carbapenemase-producing Enterobacteriaceae have the potential to rapid dissemination in healthcare settings, becoming a major infection control and public health concern. PCR remains the reference method for identifying these strains, but is still expensive. We evaluated the performance of four phenotypic tests for identifying OXA-48-producing (Oxacillinase-48) Enterobacteriaceae. These were modified Hodge test (MHT), a combination disk test with meropenem alone or in combination with various inhibitors and temocillin, an enzymatic test and an immunochromatographic test. The tests were performed and interpreted according to guidelines or manufacturer’s recommendations. The most frequent microorganism included in the study was Klebsiella pneumoniae. All the tests had 100% specificity, except MHT (87,5%). Sensitivity was 91,25% for MHT, 90% for the combination disk test, 95% for the enzymatic test and 82,50% for the immunochromatographic test.

Keywords

• enterobacteriaceae
• oxa-48 carbapenemase
• phenotypic tests