Use of sequence-based typing and multiplex PCR to identify clonal lineages of outbreak strains of Acinetobacter baumannii

Abstract

Representatives (n = 31) of outbreak strains of Acinetobacter baumannii from five countries fell into three clear groups, designated Groups 1-3, based on their ompA (outer-membrane protein A), csuE (part of a pilus assembly system required for biofilm formation) and bla(OXA-51-like) (the intrinsic carbapenemase gene in A. baumannii) gene sequences. With the exception of the closely related alleles within the Group 1 clonal complex, alleles at each locus were highly distinct from each other, with a minimum of 14 nucleotide differences between any two alleles. Isolates within a group shared the same combination of alleles at the three loci, providing compelling evidence that the outbreak strains investigated belonged to three clonal lineages. These corresponded to the previously identified European clones I-III. Sequence differences among the alleles were used to design multiplex PCRs to rapidly assign isolates belonging to particular genotypes to sequence groups. In the UK, genotypes belonging to the Group 1 clonal complex have been particularly successful, accounting for the vast majority of isolates referred from hospitals experiencing problems with Acinetobacter.

Significant spread of extensively drug-resistant Acinetobacter baumannii genotypes of clonal complex 92 among intensive care unit patients in a university hospital in southern Iran

“…In addition, we found a high prevalence (98 %) of the bla OXA-23 -like gene across different genotypes. These results are consistent with observations reported from various parts of the world, and they explain the high risk of failure of carbapenem treatment in A. baumannii infections [14,[29][30][31][32][33][34].…”

Molecular identification of tigecycline- and colistin-resistant carbapenemase-producing Acinetobacter baumannii from a Greek hospital from 2011 to 2013

“…Of the seven bla OXA-23 producers of 3LST ST101, five isolates were tigecycline resistant and two were colistin resistant. The 3LST ST101 (ompA-csuE-bla OXA-51 -like allelic profile: 1-1-1; ST group 1) corresponds to the international clone II, which has previously been associated with divergent bla OXA-23 -producing strains in several countries worldwide, including Greece (Liakopoulos et al, 2012;Turton et al, 2007;Zarrilli et al, 2013); thus, the acquisition of tigecycline and colistin resistance in strains of this clone is worrying for the therapeutic options and infection control policies for MDR A. baumannii.…”

“…Genotyping by the 3LST scheme was performed as previously described (http://www.hpa-bioinformatics. org.uk/AB/; Turton et al, 2007).…”

Prevalence and diversity of carbapenemases among imipenem-nonsusceptible Acinetobacter isolates in Korea: emergence of a novel OXA-182

“…PFGE banding patterns were analyzed with the BioNumerics software v.5.10 (Applied Maths, Sint-Martens-Latem, Belgium) to generate a dendrogram, which was based on the unweighted pair group method using arithmetic averages (UPGMA) from the Dice coefficient. Multiplex PCRs for identification of the ompA, csuE, and bla OXA-51 -like sequence groups were performed as described by Turton et al (2007).…”