The Perfect Substrates for Laborotory Detection of Extended-spectrum β-Lactamases

OBJECTIVE To investigate ESBLs detection of our district to provide an exact and economical test for rudimentary clinical laboratory and to prevent the spread of producing extended spectrum β lactamases strains. METHODS Disk diffusion screening and phenotypic confirmatory tests for ESBLs of the National Committee for Clinical Laboratory Standards (NCCLS) approved standard M100 S9 were taken. RESULTS The detection rate of screening for ESBLs in Enterobacteriaceae is varied depending on different antimicrobial agents being tested. The lowest detection rate (76.3%) for ceftazidime was showed, but the highest (97.4%) was for aztreonam and cefotaxime. In phenotypic confirmatory test, the detection rate for cefotaxime was higher than ceftazidime (P0.05, respectively). CONCLUSIONS Rudimentary clinical laboratory personnel can screen for ESBLs production in bacteria by using aztreonam and cefotaxime, and perform the phenotypic confirmatory test by using cefotaxime and cefotaxime/clavulanic acid.