Carbapenems-resistance gram negative bacteria of the metallo-beta-lactamase enzyme by phenotypic methods investigation

Carbapenems are the most frequently used antibiotics in the treatment of multi-drug resistant Gram negative bacterial infections. One of the major important mechanisms of carbapenem resistance is production of metallo-beta-lactamases. Metallo-beta-lactamases genes reside on chromosome or plasmids and easily spread among bacterial strains. Our study Balcalı Hospital Central Laboratory of Clinical sent to the Microbiology unit isolated from various samples and resistance to carbapenems in Gram-negative bacteria to determine the rate by phenotypic methods of producing strains metallo-beta-lactamases enzymes, to compare these phenotypic methods for the determination of metallo-beta-lactamases and using phenotypic methods in metallo-beta-lactamases production was intended to be which may be more useful in applications of the routine. For this purpose, from June to October 2012 and February-March 2014 sent to the Central Laboratory of carbapenem of materials from various clinics in Gram-negative bacteria resistant to 261 metallo-beta-lactamases production was investigated by phenotypic methods. Identification of bacteria and antibiotic resistance of Clinical and Laboratory Standards Institute in accordance with the recommendations were determined by Vitek 2 automated system. The production of metallo-beta-lactamases was investigated with modified Hodge test, combined disk diffusion, and double-disk synergy test. Among carbapenem resistant strains imipenem 90.4%, meropenem 74.3%, and ertapenem 46.6% were found to be resistant. Carbapenem resistant Gram-negative bacteria strains metallo-beta-lactamases production by modified Hodge test 76.2%, combined disk diffusion 27.2%, and with double-disk synergy test was 14.2%, respectively. The most production of metallo-beta-lactamases strains with modified Hodge test and combined disk diffusion test was A. baumannii, the most production of metallo-beta-lactamases strains with double-disk synergy test was P.aeruginosa as an detected. Metallo-Beta-Lactamase to study fast, simple, sensitivity and specificity is high, there is a need for a good phenotypic screening method. In light of these findings, phenotypic method can be used in which of the routines in the topic, this determination of molecular methods of production of the fact that the strains that produce metallo-beta-lactamases revealed.