Molecular epidemiology of outbreaks and containment of drug-resistant Pseudomonas aeruginosa in a Tokyo hospital

Sekiguchi, Jun‐ichiro; Teruya, Katsuji; Horii, Kumi; Kuroda, Emi; Konosaki, Hisami; Mizuguchi, Yukie; Araake, Minako; Kawana, Akihiko; Yasuda, Hiroshi; Kuratsuji, Tadatoshi; Miyazaki, Hisayoshi; Kirikae, Teruo

doi:10.1007/s10156-007-0560-5

Cited by 26 publications

(16 citation statements)

References 5 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In particular, the resistance of multidrug resistant Pseudomonas aeruginosa (MDRP) to major antipseudomonal agents, such as carbapenems, quinolones, and aminoglycosides [1], [2], has been demonstrated and is known to cause nosocomial outbreaks in Japan [3], [4]. P. aeruginosa has natural intrinsic resistance tendencies, and MDRPs have complex resistance mechanisms [5], [6].…”

Section: Introductionmentioning

confidence: 99%

Evaluation of Multidrug Efflux Pump Inhibitors by a New Method Using Microfluidic Channels

et al. 2011

View full text Add to dashboard Cite

Fluorescein-di-β-d-galactopyranoside (FDG), a fluorogenic compound, is hydrolyzed by β-galactosidase in the cytoplasm of Escherichia coli to produce a fluorescent dye, fluorescein. We found that both FDG and fluorescein were substrates of efflux pumps, and have developed a new method to evaluate efflux-inhibitory activities in E. coli using FDG and a microfluidic channel device. We used E. coli MG1655 wild-type, ΔacrB (ΔB), ΔtolC (ΔC) and ΔacrBΔtolC (ΔBC) harboring plasmids carrying the mexAB-oprM (pABM) or mexXY-oprM (pXYM) genes of Pseudomonas aeruginosa. Two inhibitors, MexB-specific pyridopyrimidine (D13-9001) and non-specific Phe-Arg-β-naphthylamide (PAβN) were evaluated. The effects of inhibitors on pumps were observed using the microfluidic channel device under a fluorescence microscope. AcrAB-TolC and analogous pumps effectively prevented FDG influx in wild-type cells, resulting in no fluorescence. In contrast, ΔB or ΔC easily imported and hydrolyzed FDG to fluorescein, which was exported by residual pumps in ΔB. Consequently, fluorescent medium in ΔB and fluorescent cells of ΔC and ΔBC were observed in the microfluidic channels. D13-9001 substantially increased fluorescent cell number in ΔBC/pABM but not in ΔBC/pXYM. PAβN increased medium fluorescence in all strains, especially in the pump deletion mutants, and caused fluorescein accumulation to disappear in ΔC. The checkerboard method revealed that D13-9001 acts synergistically with aztreonam, ciprofloxacin, and erythromycin only against the MexAB-OprM producer (ΔBC/pABM), and PAβN acts synergistically, especially with erythromycin, in all strains including the pump deletion mutants. The results obtained from PAβN were similar to the results from membrane permeabilizer, polymyxin B or polymyxin B nonapeptide by concentration. The new method clarified that D13-9001 specifically inhibited MexAB-OprM in contrast to PAβN, which appeared to be a substrate of the pumps and permeabilized the membranes in E. coli.

show abstract

Section: Introductionmentioning

confidence: 99%

Evaluation of Multidrug Efflux Pump Inhibitors by a New Method Using Microfluidic Channels

et al. 2011

View full text Add to dashboard Cite

show abstract

“…The most serious problem has been the emergence of multidrug-resistant (MDR) P. aeruginosa strains with resistance to all ␤-lactams, aminoglycosides, and quinolones (39,40). In Japan, MDR P. aeruginosa is defined as having resistance to carbapenem (MIC Ն 16 g/ml), amikacin (AMK; MIC Ն 32 g/ml), and fluoroquinolone (MIC Ն 4 g/ml).…”

mentioning

confidence: 99%

AAC(6′)-Iaf, a Novel Aminoglycoside 6′- N -Acetyltransferase from Multidrug-Resistant Pseudomonas aeruginosa Clinical Isolates

Kitao

Miyoshi‐Akiyama²,

Kirikae³

2009

Antimicrob Agents Chemother

Self Cite

View full text Add to dashboard Cite

We report here the characterization of a novel aminoglycoside resistance gene, aac(6)-Iaf, present in two multidrug-resistant (MDR) Pseudomonas aeruginosa clinical isolates. These isolates, IMCJ798 and IMCJ799, were independently obtained from two patients, one with a urinary tract infection and the other with a decubitus ulcer, in a hospital located in the western part of Japan. Although the antibiotic resistance profiles of IMCJ798 and IMCJ799 were similar to that of MDR P. aeruginosa IMCJ2.S1, which caused outbreaks in the eastern part of Japan, the pulsed-field gel electrophoresis patterns for these isolates were different from that for IMCJ2.S1. Both IMCJ798 and IMCJ799 were found to contain a novel chromosomal class 1 integron, In123, which included aac(6)-Iaf as the first cassette gene. The encoded protein, AAC(6)-Iaf, was found to consist of 183 amino acids, with 91 and 87% identity to AAC(6)-Iq and AAC(6)-Im, respectively. IMCJ798, IMCJ799, and Escherichia coli transformants carrying a plasmid containing the aac(6)-Iaf gene and its upstream region were highly resistant to amikacin, dibekacin, and kanamycin but not to gentamicin. The production of AAC(6)-Iaf in these strains was confirmed by Western blot analysis. Thin-layer chromatography indicated that AAC(6)-Iaf is a functional acetyltransferase that specifically modifies the amino groups at the 6 positions of aminoglycosides. Collectively, these findings indicate that AAC(6)-Iaf contributes to aminoglycoside resistance.

show abstract

“…Most previous studies have reported the contamination of computer interface surfaces by potential pathogens such as Methicillin-resistant Staphylococcus aureus (MRSA) [3,8]and Acinetobacter baumannii [9], but few have studied the relationship between contamination of the ward computers and clinical isolates in hospitals with improved hand hygiene compliance and during a non-outbreak period. Clinically, A. baumannii , P. aeruginosa , and MRSA cause the most common nosocomial infections and their presence correlates with environmental surface contamination [10-12]. We conducted a hospital-based surveillance study of these three important pathogens on computer interface surfaces in different ward settings and then examined the relationship of contaminated computer interface surfaces with the presence of clinical isolates in these wards during a non-outbreak period.…”

Section: Introductionmentioning

confidence: 99%

Methicillin-resistant Staphylococcus aureus and Acinetobacter baumanniion computer interface surfaces of hospital wards and association with clinical isolates

Siu

Chen

et al. 2009

BMC Infect Dis

View full text Add to dashboard Cite

BackgroundComputer keyboards and mice are potential reservoirs of nosocomial pathogens, but routine disinfection for non-water-proof computer devices is a problem. With better hand hygiene compliance of health-care workers (HCWs), the impact of these potential sources of contamination on clinical infection needs to be clarified.MethodsThis study was conducted in a 1600-bed medical center of southern Taiwan with 47 wards and 282 computers. With education and monitoring program of hand hygiene for HCWs, the average compliance rate was 74% before our surveillance. We investigated the association of methicillin-resistant Staphylococcus aureus (MRSA), Pseudomonas aeruginosa and Acinetobacter baumannii, three leading hospital-acquired pathogens, from ward computer keyboards, mice and from clinical isolates in non-outbreak period by pulsed field gel electrophoresis and antibiogram.ResultsOur results revealed a 17.4% (49/282) contamination rate of these computer devices by S. aureus, Acinetobacter spp. or Pseudomonas spp. The contamination rates of MRSA and A. baumannii in the ward computers were 1.1% and 4.3%, respectively. No P. aeruginosa was isolated. All isolates from computers and clinical specimens at the same ward showed different pulsotypes. However, A. baumannii isolates on two ward computers had the same pulsotype.ConclusionWith good hand hygiene compliance, we found relatively low contamination rates of MRSA, P. aeruginosa and A. baumannii on ward computer interface, and without further contribution to nosocomial infection. Our results suggested no necessity of routine culture surveillance in non-outbreak situation.

show abstract

Molecular epidemiology of outbreaks and containment of drug-resistant Pseudomonas aeruginosa in a Tokyo hospital

Cited by 26 publications

References 5 publications

Evaluation of Multidrug Efflux Pump Inhibitors by a New Method Using Microfluidic Channels

Evaluation of Multidrug Efflux Pump Inhibitors by a New Method Using Microfluidic Channels

AAC(6′)-Iaf, a Novel Aminoglycoside 6′- N -Acetyltransferase from Multidrug-Resistant Pseudomonas aeruginosa Clinical Isolates

Methicillin-resistant Staphylococcus aureus and Acinetobacter baumanniion computer interface surfaces of hospital wards and association with clinical isolates

Contact Info

Product

Resources

About