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Objective: In this study; we aimed to determine metallo beta-lactamase production in 29 Pseudomonas aeruginosa isolates resistant to carbapenems that isolated as a cause of nosocomial infection and to compare the three different phenotypic methods for screening of metallo beta-lactamase production. Material and Methods: P.aeruginosa isolates were identified by conventional methods. Antibiotic susceptibility tests were performed by Kirby-Bauer disk diffusion method according to the standards of Clinical and Laboratory Standards Institute. İmipenem and meropenem E tests (AB Biodisk, Sweden) were used for verification of carbapenem resistance. Metallo beta-lactamase E test (AB Biodisk, Sweden), modified Hodge test and imipenem-EDTA combined disk test were used for detection of metallo beta-lactamase production and the results of these tests were compared with polymerase chain reaction results. Results: IMP, VIM, GIM, SIM and SPM type genes were negative for all isolates with polymerase chain reaction. As a screening test for metallo beta-lactamase enzymes, combined disk test and E test detected positivity for six and two isolates, respectively. Modified Hodge test yielded 10 positive and two undetermined results within 29 isolates. There were no statistical difference between metallo beta-lactamase E test results and polymerase chain reaction results (p> 0,05 ). But, there were significantly statistical difference between polymerase chain reaction results and combined disk test (p:0,023 ) and modified Hodge test (p <0,001) results. Conclusion: According to our results; metallo beta-lactamase E test is suitable method for screening metallo beta-lactamase enzymes in carbapenem resistant P.aeruginosa isolates, however; positive results of this test should be confirmed with molecular methods. [ABSTRACT FROM AUTHOR]