Evaluation of clonality and carbapenem resistance mechanisms among Acinetobacter baumannii-Acinetobacter calcoaceticus complex and Enterobacteriaceae isolates collected in European and Mediterranean countries and detection of two novel β-lactamases, GES-2

We evaluated doripenem-resistant Acinetobacter baumannii-Acinetobacter calcoaceticus complex (ACB; n = 411) and Enterobacteriaceae (n = 92) isolates collected from patients from 14 European and Mediterranean countries during 2009 to 2011 for the presence of carbapenemase-encoding genes and clonality. Following susceptibility testing, carbapenem-resistant (doripenem MIC, >2 μg/ml) isolates were screened for carbapenemases. New β-lactamase genes were expressed in a common background and susceptibility was tested. Class 1 integrons were sequenced. Clonality was evaluated by pulsed-field gel electrophoresis and multilocus sequence typing (Pasteur scheme). Relative expression of β-lactam intrinsic resistance mechanisms was determined for carbapenemase-negative Enterobacteriaceae. ACB and Enterobacteriaceae displayed 58.9 and 0.9% doripenem resistance, respectively. bla(OXA-23), bla(OXA-58), and bla(OXA-24/OXA-40) were detected among 277, 77, and 29 ACB, respectively (in 8, 6, and 5 countries). Ten Turkish isolates carried bla(GES-11) or bla(GES-22). GES-22 (G243A and M169L mutations in GES-1) had an extended-spectrum β-lactamase profile. A total of 33 clusters of ≥ 2 ACB isolates were observed, and 227 isolates belonged to sequence type 2/international clone II. Other international clones were limited to Turkey and Israel. Doripenem-resistant Enterobacteriaceae increased significantly (0.7 to 1.6%), and 15 blaKPC-2- and 22 blaKPC-3-carrying isolates, mostly belonging to clonal complexes 11 and 258, were observed. Enterobacteriaceae isolates producing OXA-48 (n = 16; in Turkey and Italy), VIM-1 (n = 10; in Greece, Poland, and Spain), VIM-26 (n = 1; in Greece), and IMP-19, VIM-4, and the novel VIM-35 (n = 1 each from Poland) were detected. VIM-35 had one substitution compared to VIM-1 (A235T) and a similar susceptibility profile. One or more resistance mechanisms were identified in 4/6 carbapenemase-negative Enterobacteriaceae. This broad evaluation confirms results from country-specific surveys and shows a highly diverse population of carbapenemase-producing ACB and Enterobacteriaceae in Europe and Mediterranean countries.

Castanheira M ，Costello SE ，Woosley LN ，Deshpande LM ，Davies TA ，Jones RN ... -  《-》

OXA-Carbapenemases Present in Clinical Acinetobacter baumannii-calcoaceticus Complex Isolates from Patients in Kurdistan Region, Iraq.

Ganjo AR ，Maghdid DM ，Mansoor IY ，Kok DJ ，Severin JA ，Verbrugh HA ，Kreft D ，Fatah MH ，Alnakshabandi AA ，Dlnya A ，Hammerum AM ，Ng K ，Goessens W ... -  《-》

A diversity of OXA-carbapenemases and class 1 integrons among carbapenem-resistant Acinetobacter baumannii clinical isolates from Sweden belonging to different international clonal lineages.

Karah N ，Giske CG ，Sundsfjord A ，Samuelsen Ø ... -  《-》

Carbapenem susceptibility testing errors using three automated systems, disk diffusion, Etest, and broth microdilution and carbapenem resistance genes in isolates of Acinetobacter baumannii-calcoaceticus complex.

Markelz AE ，Mende K ，Murray CK ，Yu X ，Zera WC ，Hospenthal DR ，Beckius ML ，Calvano T ，Akers KS ... -  《-》

Typing and characterization of carbapenem-resistant Acinetobacter calcoaceticus-baumannii complex in a Chinese hospital.

Yu YS ，Yang Q ，Xu XW ，Kong HS ，Xu GY ，Zhong BY ... -  《JOURNAL OF MEDICAL MICROBIOLOGY》