The MAST® D68C test: an interesting tool for detecting extended-spectrum β-lactamase (ESBL)-producing Enterobacteriaceae

Archive ouverte

Nourrisson, C. | Tan, R. N. | Hennequin, C. | Gibold, L. | Bonnet, R. | Robin, F.

Edité par CCSD ; Springer Verlag -

International audience. The MastA (R) D68C test is a phenotypical test that allows the detection of extended-spectrum beta-lactamase (ESBL) production, even in AmpC-producing Enterobacteriaceae. We assessed its detection accuracy against a large collection of 106 Enterobacteriaceae isolates producing a wide diversity of well-characterized beta-lactamases (53 ESBL producers, 25 Amp. producers, seven AmpC and ESBL producers, five carbapenemase producers, three carbapenemase and ESBL producers, one AmpC, carbapenemase, and ESBL producer, three TEM-1 producers, three SHV-1 producers, three OXA-1 producers, and one hyperOXY producer, ATCC 35218, ATCC 25922 [a beta-lactamase-negative control strain]). The results were compared with those of the double disk test and the Clinical and Laboratory Standards Institute (CLSI) confirmatory test for the detection of ESBL. The sensitivity was 90.6 % for the synergy test, 87.5 % for the CLSI method, and only 73.1 % for D68C, which, however, reached 92.1 % if the strains for which supplementary investigations were recommended and the complex mutant TEM (CMT)-producing strains were excluded versus 94.1 % and 88.2 % for the other methods. The specificity was 90.2 % for the synergy test and 100 % for the CLSI method and D68C. D68C was also efficient in detecting AmpC-overproducing strains (sensitivity = 97 %, specificity = 95.9 %): among the 74 strains belonging to natural AmpC-producing species, the sensitivity and specificity were 100 and 94.8 %, respectively. The MastA (R) D68C-test is a promising method that is easy to perform for the detection of current ESBLs and could also be useful for the detection of plasmid-encoded AmpC enzymes (sensitivity = 100 %).

Consulter en ligne

Suggestions

Du même auteur

Rapid detection of AAC(6’)-Ib-cr production using a MALDI-TOF MS strategy

Archive ouverte | Pardo, C.-A. | CCSD

International audience. Plasmid-mediated quinolone resistance mechanisms have become increasingly prevalent among Enterobacteriaceae strains since the 1990s. Among these mechanisms, AAC(6')-Ib-cr is the most difficu...

IS1R-Mediated Plasticity of IncL/M Plasmids Leads to the Insertion of bla(OXA-48) into the Escherichia coli Chromosome

Archive ouverte | Beyrouthy, R. | CCSD

International audience. The OXA-48 carbapenemase is mainly encoded by similar to 62-kb IncL/ M plasmids. However, chromosome-mediated genes have been observed in Escherichia coli isolates. In this work, we investiga...

Lactobacillus rhamnosus Meningitis following Recurrent Episodes of Bacteremia in a Child Undergoing Allogeneic Hematopoietic Stem Cell Transplantation

Archive ouverte | Robin, F. | CCSD

International audience. We report a case of meningitis due to Lactobacillus rhamnosus in a child undergoing allogeneic hematopoietic stem cell transplantation for acute leukemia. Four episodes of bacteremia involvin...

Chargement des enrichissements...