AmpC β-lactamases are Ambler class C enzymes that can be divided into three categories: (1) inducible resistance (e.g., Enterobacter cloacae, Citrobacter freundii), (2) non-inducible chromosomal resistance due to mutations (e.g., Escherichia coli, Shigella spp., Acinetobacter baumannii), and (3) plasmid-mediated resistance (e.g., Klebsiella ...

This review summarizes mechanisms of resistance resulting in AmpC expression, triggers of AmpC expression, the species-specific epidemiology of AmpC β-lactamase production, approaches to the detection of AmpC production, and treatment approaches for infections caused by AmpC β-lactamase–producing bacteria.

2022年4月6日 · Enterobacterales considered at significant risk of clinically meaningful AmpC production (sometimes abbreviated ‘ HECK-Yes ’) include Enterobacter cloacae, Citrobacter freundii and Klebsiella aerogenes. These organisms can cause infections in the urinary tract, soft tissue, gastrointestinal tract and lower respiratory tract.

2023年11月27日 · Recent guidance from IDSA recommends meropenem for treatment of organisms at moderate-high risk for inducible chromosomal AmpC β-lactamase hyperproduction (AmpC organisms) with a cefepime minimum inhibitory concentration (MIC) of 4-8 mCg/mL (susceptible dose-dependent or S-DD).1 This runs contrary to …

2020年7月2日 · Piperacillin/tazobactam may remain effective and may be less selective for AmpC derepressed mutants than cephalosporins. The potential roles for agents such as cefepime or trimethoprim/sulfamethoxazole are also discussed. Clinical studies that better define optimal treatment for this group of bacteria are required. Crown Copyright © 2012.

2024年1月2日 · Among its Gram-negative members, Pseudomonas aeruginosa and Enterobacter cloacae predominantly base β-lactam resistance on their intrinsic chromosomal class C inducible cephalosporinase (AmpC), a...

AmpC β-lactamases are clinically important cephalosporinases encoded on the chromosomes of many of the Enterobacteriaceae and a few other organisms, where they mediate resistance to cephalothin, cefazolin, cefoxitin, most penicillins, and β …

2017年8月24日 · We read the recent paper by Cheng et al. with interest and commend the authors for assessing the clinically important question of whether piperacillin-tazobactam can be used as definitive therapy for bacteremia caused by Enterobacteriaceae harboring inducible AmpC β-lactamases ( 1 ).

2019年6月10日 · The present study was conducted to search the fecal carriage rates of (i) Enterobacteriaceae that produce extended-spectrum β-lactamase (ESBL-E) and/or (ii) plasmid-mediated AmpC β-lactamase (pAmpC-E), (iii) ciprofloxacin-resistant Enterobacteriaceae (CIP-RE), and (iv) carbapenem-intermediate or -resistant Enterobacteriaceae (CIRE) in ...

2021年5月15日 · The AmpC beta-lactamase is an enzyme that is produced by Gram-negative bacteria and can hydrolyze a broad spectrum of beta-lactam antibiotics, including the aminopenicillins and 1st-, 2nd-, and 3rd-generation cephalosporins [1].