RT Journal Article
T1 Cefditoren versus ceftazidime in inducer-substrate combinations for the evaluation of AmpC production in a disc approximation test
A1 Cafini, Fabio
A1 Aguilar, Lorenzo
A1 Alou Cervera, Luis
A1 Giménez, María José
A1 Sevillano Fernández, David
A1 Torrico, Martha
A1 González Hidalgo, Natalia
A1 Coronel, Pilar
A1 Prieto Prieto, José
AB Objective: To evaluate cefditoren in inducer-substrate combinations to screen for AmpC induction.Methods: 100 clinical isolates (25 P. aeruginosa, 25 E. cloacae, 14 M. morganii, 13 S. marcescens, 12 C. freundii, 7 P. rettgeri, and 4 E. aerogenes) were tested by the Kirby-Bauer disc approximation method using cefditoren and ceftazidime discs as substrates, and cefditoren and imipenem discs as inducers.Results: None of the strains showed induction of AmpC with cefditoren-ceftazidime as inducer-substrate combination. Imipenem-cefditoren as inducer-substrate combination was not useful for evaluating strains of P. aeruginosa since no inhibition zones surrounding the cefditoren disc were found. Among evaluable enterobacteria (those showing substrate inhibition zone), inducible Amp C was detected in 48 out of 63 (76.2%) with cefditoren, and in 33 out of 68 (48.5%) isolates with ceftazidime as substrate. Significantly (p=0.013) higher number of AmpC producers were detected with cefditoren versus ceftazidime (76.2% vs. 48.5%), due to the differences found for E. cloacae (72.8% vs. 21.7%; p=0.0009) and S. marcescens (100% vs. 54.5%; p=0.03). Higher mean reductions of diameters around substrate discs were found for cefditoren (4.17 mm) vs. ceftazidime (3.79 mm), reaching statistical significance (p<0.05) for indol-positive proteae: M. morganii (5.32 mm vs. 3.92 mm) and P. rettgeri (3.47 mm vs. 2.64 mm).Conclusion: Cefditoren showed no induction capability, and when used as substrate (with imipenem as inducer) it offered detection rates of AmpC inducible enterobacteria higher than the imipenem-ceftazidime combination, mainly for Enterobacter spp. and Serratia spp., with higher diameter reductions for indol-positive proteae.
PB Sociedad Española de Quimioterapia
SN 0214-3429
YR 2010
FD 2010-06
LK https://hdl.handle.net/20.500.14352/107079
UL https://hdl.handle.net/20.500.14352/107079
LA eng
NO Cafini F, Aguilar L, Alou L, Giménez MJ, Sevillano D, Torrico M, González N, Coronel P, Prieto J. Cefditoren versus ceftazidime in inducer-substrate combinations for the evaluation of AmpC production in a disc approximation test. Rev Esp Quimioter. 2010 Jun;23(2):72-5
NO Tedec-Meiji Farma S.A.
DS Docta Complutense
RD 12 abr 2025