Utility of the ceftazidime-imipenem antagonism test (CIAT) to detect and confirm the presence of inducible AmpC beta-lactamases among enterobacteriaceae.
Detection of AmpC beta-lactamase production by enterobacteria has been problematic. Contrary to ESBLs, no specific guidelines are available for detection and confirmation of AmpC production by clinical relevant microorganisms. Moreover, some bacterial species may produce inducible AmpC beta-lactamases that can be easily overlooked by routine susceptibility tests. We reported here a new test based on the strong inducible effect of imipenem on AmpC genes and the consequent antagonism with ceftazidime. This test is very simple and proved to be helpful in detecting AmpC-inducible enzymes among several species of clinical isolates.
Cantarelli
Vlademir Vicente
VV
Microbiology sections, Weinmann Laboratório LTDA, Ramiro Barcelos 910, 90035-001 Porto Alegre, RS, Brazil. vcantarelli@weinmann.com.br
Inamine
Everton
E
Brodt
Teresa Cristina Z
TC
Secchi
Carina
C
Cavalcante
Bianca C
BC
Pereira
Fabiana de Souza
Fde S
D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001426:Bacterial Proteins / Q000096:biosynthesis / Q000187:drug effects* / Q000235:genetics; D002442:Ceftazidime / Q000494:pharmacology*; D004755:Enterobacteriaceae / Q000187:drug effects* / Q000201:enzymology; D006801:Humans; D015378:Imipenem / Q000494:pharmacology*; D010641:Phenotype; D001618:beta-Lactamases / Q000096:biosynthesis / Q000187:drug effects* / Q000235:genetics
D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D015378:Imipenem; D002442:Ceftazidime; C048795:AmpC beta-lactamases; D001618:beta-Lactamases