Molecular investigation of two clusters ofhospital-acquired bacteraemia caused by multi-resistant Klebsiella pneumoniae using pulsed-field gel electrophoresis andinfrequent restriction site PCR

ABSTRACT High-level resistance to aminoglycosides produced by 16S rRNA methylases in Enterobacteriaceae isolates was investigated. The prevalences of armA in Escherichia coli, Klebsiella pneumoniae, and Enterobacter cloacae were 0.6%, 3.0%, and 10%, respectively. rmtB was more prevalent than armA. Pulsed-field gel electrophoresis patterns indicated that armA and rmtB have spread horizontally and clonally.

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Validity of SmaI-defined genotypes of Campylobacter jejuni examined by SalI, KpnI, and BamHI polymorphisms: evidence of identical clones infecting humans, poultry, and cattle

Epidemiology and Infection ◽

10.1017/s0950268898008668 ◽

1998 ◽

Vol 120 (3) ◽

pp. 231-237 ◽

Cited By ~ 89

Author(s):

S. L. W. ON ◽

E. M. NIELSEN ◽

J. ENGBERG ◽

M. MADSEN

Keyword(s):

Campylobacter Jejuni ◽

Gel Electrophoresis ◽

Restriction Site ◽

Epidemiological Studies ◽

Pulsed Field Gel Electrophoresis ◽

Genetic Differences ◽

Genetic Fingerprinting ◽

Molecular Subtyping ◽

Pulsed Field ◽

Heat Stable

We describe here an examination of the validity of molecular types of Campylobacter jejuni as defined by separation of SmaI-digested DNA using pulsed-field gel electrophoresis (PFGE), recently suggested as part of a molecular subtyping scheme. Thirty-four Danish strains from humans, water, poultry and cattle were assigned to one of six SmaI ‘profile groups’ (PGs), with two additional strains included as genotypically distinct controls. The interstrain relationships were reexamined by PFGE of SalI, KpnI and BamHI-digested DNA, and also by serotyping with heat-stable antigens. All outbreak-related strains were indistinguishable by all criteria, as were two sets of two randomly-isolated human strains. Two groups of indistinguishable isolates contained randomly isolated strains from more than one source (poultry, humans and/or cattle), a finding with significant epidemiological connotations. All ‘genetically identical’ strains belonged to the same serotype, whereas genetic differences were detected between strains assigned to the same SmaI PG but differing in serotype. We conclude that PFGE-based genetic fingerprinting can yield invaluable data for epidemiological studies of sporadic C. jejuni infection, but that results based on one restriction site polymorphism must be checked with another enzyme.

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Emergence ofKlebsiella pneumoniaeCoproducing KPC-2 and 16S rRNA Methylase ArmA in Poland

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.00386-10 ◽

2010 ◽

Vol 55 (1) ◽

pp. 443-446 ◽

Cited By ~ 23

Author(s):

Katarzyna Zacharczuk ◽

Katarzyna Piekarska ◽

Jolanta Szych ◽

Elwira Zawidzka ◽

Agnieszka Sulikowska ◽

...

Keyword(s):

16S Rrna ◽

Klebsiella Pneumoniae ◽

Gel Electrophoresis ◽

Variable Region ◽

Pulsed Field Gel Electrophoresis ◽

Epidemic Strain ◽

Pulsed Field ◽

Ca 50 ◽

16S Rrna Methylase

ABSTRACTAKlebsiella pneumoniaeepidemic strain that coproduced carbapenemase KPC-2 (K. pneumoniaecarbapenemase 2) and 16S rRNA methylase ArmA has emerged in Poland. Four nonduplicate isolates from patients in a hospital in Warsaw, Poland, were found to carry theblaKPC-2andarmAgenes on ca. 50-kb and 90-kb plasmids, respectively. Tn4401with a 100-bp deletion in the variable region was detected in all the isolates. XbaI pulsed-field gel electrophoresis (PFGE) revealed 93.2% similarity of the isolates. All the isolates were resistant to carbapenems and 4,6-disubstituted 2-deoxystreptamines.

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Clinical Isolates of Enterobacteriaceae Producing Extended-Spectrum β-Lactamases: Prevalence of CTX-M-3 at a Hospital in China

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.47.2.790-793.2003 ◽

2003 ◽

Vol 47 (2) ◽

pp. 790-793 ◽

Cited By ~ 54

Author(s):

Hui Wang ◽

Swathi Kelkar ◽

Weiyuan Wu ◽

Minjun Chen ◽

John P. Quinn

Keyword(s):

Escherichia Coli ◽

Klebsiella Pneumoniae ◽

Teaching Hospital ◽

Gel Electrophoresis ◽

Enterobacter Cloacae ◽

Pulsed Field Gel Electrophoresis ◽

Clinical Isolates ◽

Citrobacter Freundii ◽

Pulsed Field ◽

Extended Spectrum

ABSTRACT The prevalence of extended-spectrum β-lactamase-producing strains was demonstrated in 5 of 44 (11.4%) Escherichia coli, 17 of 43 (39.5%) Klebsiella pneumoniae, 3 of 50 (6.0%) Enterobacter cloacae, and 2 of 25 (8.0%) Citrobacter freundii strains at a teaching hospital in China. Nineteen of these 27 strains expressed CTX-M-3 β-lactamase (pI 8.6). A subset of the clinical isolates expressing the CTX-M-3 enzyme, tested by pulsed-field gel electrophoresis, revealed multiple clones. Five isolates expressed a novel enzyme, SHV-43 (pI 8.0), which had two substitutions (Leu113Phe and Thr149Ser) compared with SHV-1.

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