title: In vitro susceptibility of characterized β-lactamase-producing Gram-negative bacteria isolated in Japan to ceftazidime-, ceftaroline-, and aztreonam-avibactam combinations.
abstract: Avibactam displays potent inhibition of extended-spectrum, AmpC, KPC and some OXA β-lactamases. We examined the combinations of avibactam with ceftazidime, ceftaroline and aztreonam by the broth microdilution method against Gram-negative bacteria harboring molecularly-characterized β-lactamase genes collected in Toho University, Japan. Bacterial isolates included: Ambler class A β-lactamase-producing Enterobacteriaceae (n = 26); class C β-lactamase-producing Enterobacteriaceae (n = 9) and class D β-lactamase-producing Acinetobacter baumannii (n = 9) and Enterobacteriaceae (n = 3). Ceftazidime-avibactam, ceftaroline-avibactam ands aztreonam-avibactam were active against the strains with an extended-spectrum β-lactamase (ESBL) or AmpC enzymes, but combination with avibactam did not reduce β-lactam MICs against A. baumannii with OXA β-lactamases including carbapenemases, such as OXA-40 and -69.
authors.affiliation: Department of Microbiology and Infectious Diseases, Faculty of Medicine, Toho University School of Medicine, Tokyo 143-8540, Japan.
authors.forename: Ayumi
authors.initials: A
authors.lastname: Yoshizumi
authors.affiliation: Department of Microbiology and Infectious Diseases, Faculty of Medicine, Toho University School of Medicine, Tokyo 143-8540, Japan. Electronic address: yishii@med.toho-u.ac.jp.
authors.forename: Yoshikazu
authors.initials: Y
authors.lastname: Ishii
authors.affiliation: Department of Microbiology and Infectious Diseases, Faculty of Medicine, Toho University School of Medicine, Tokyo 143-8540, Japan.
authors.forename: Kotaro
authors.initials: K
authors.lastname: Aoki
authors.affiliation: AstraZeneca Pharmaceuticals LP, Waltham, MA, USA.
authors.forename: Raymond
authors.initials: R
authors.lastname: Testa
authors.affiliation: AstraZeneca Pharmaceuticals LP, Waltham, MA, USA.
authors.forename: Wright W
authors.initials: WW
authors.lastname: Nichols
authors.affiliation: Department of Microbiology and Infectious Diseases, Faculty of Medicine, Toho University School of Medicine, Tokyo 143-8540, Japan.
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Tateda
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D053961:Azabicyclo Compounds / Q000494:pharmacology*; D024901:Drug Resistance, Multiple, Bacterial; D006090:Gram-Negative Bacteria / Q000187:drug effects* / Q000201:enzymology; D016905:Gram-Negative Bacterial Infections / Q000453:epidemiology / Q000382:microbiology*; D006801:Humans; D007564:Japan / Q000453:epidemiology; D008826:Microbial Sensitivity Tests; D001618:beta-Lactamases; D047090:beta-Lactams / Q000494:pharmacology*
chemical_list: D000900:Anti-Bacterial Agents; D053961:Azabicyclo Compounds; D047090:beta-Lactams; C543519:avibactam; D001618:beta-Lactamases
keywords: Antibiotic resistance; Avibactam; Aztreonam–avibactam; Ceftaroline–avibactam; Ceftazidime–avibactam