OBJECTIVE: To assess the occurrence of the genes of the AdeABC efflux system and their association with antimicrobial resistance in Acinetobacter baumannii. METHODS: A set of 116 strains selected for their diversity both in genotypic properties and geographic origin was investigated for the presence of the structural (adeA, adeB and adeC) and regulatory (adeR and adeS) genes of the AdeABC system by PCR, for resistance to 11 antimicrobials by disc diffusion, for MIC of netilmicin and for the presence of aacC2 and aacA4, encoding netilmicin-modifying enzymes. RESULTS: Ninety-five strains were positive for adeA, adeB, adeR and adeS, 10 were positive for 1 to 3 of these genes and 11 were negative for all genes. The adeC gene was found in 49 strains with one or more of the other genes. Forty-one strains were resistant to a maximum of one agent and 75 strains to two or more agents. Netilmicin MICs showed an almost bimodal distribution with respective peaks of 0.5-1 and 8 mg/L; aacC2 or aacA4 was found in six strains with netilmicin MIC of >or=64 mg/L. All 61 strains with netilmicin MICs >or= 4 mg/L were both adeABRS-positive and resistant to two or more agents, whereas netilmicin MICs
- MeSH
- ATP-Binding Cassette Transporters genetics metabolism MeSH
- Acinetobacter baumannii genetics metabolism drug effects MeSH
- Anti-Bacterial Agents pharmacology MeSH
- Genes, Bacterial genetics MeSH
- DNA Fingerprinting MeSH
- Genotype MeSH
- Acinetobacter Infections microbiology MeSH
- Humans MeSH
- Microbial Sensitivity Tests MeSH
- Drug Resistance, Multiple, Bacterial genetics MeSH
- Netilmicin pharmacology MeSH
- Reverse Transcriptase Polymerase Chain Reaction MeSH
- Up-Regulation drug effects MeSH
- Check Tag
- Humans MeSH
Význam gramnegatívnej baktérie Stenotrophomonas maltopbilia, spôsobujúcej infekcie u imunodeficientních pacientov, v poslednej dobe vzrastá hlavne kvôli prirodzenej rezistencii voči mnohým antimikróbnym látkam. Cieľom štúdie bolo zistiť postantibiotický účinok (PAE) vybraných aminoglykozidov a charakterizovať jeho pôsobenie na niektoré biologické vlastnosti klinických izolátor S. maltophilia. PAE sa určil použitím suprainhibičných koncentrácií 2x a 4x minimálna inhibičná koncentrácia (MIC) amikacínu, netilmicínu a tobramycínu pri 37 °C 24 h v Mulerovom-Hintonovom bujóne (MHB). Metódou adherencie na xylén a soľnoagregačným testom sa stanovila povrchová hydrofobicita buniek S. malíophilia, dalei sa hodnotila motilita a produkcia lipázy u testovaných kmeňov. Najdlhší PAE – priemerne 2 h indukoval netilmicín u kmeňa č. 5 777. Aminoglykozidy v suprainhibičných koncentráciách neovplyvnili výraznejšie povrchovú hydrofobicitu ani motilitu u testovaných kmeňov. Netilmicín najvýraznejšie inhiboval produkciu lipázy v koncentrácii 4x MIC u kmeňa č. 27 823. Zistené účinky suprainhibičných koncentrácií aminoglykozidov na S. ma/tophiiia boli všeobecne nižšie jako při iných gramnegatívnych baktériách.
Recently, the importance of a gramnegative bacterium Stenotrophomonas maltophilia, causing infection in immunocompromised patients, grows rapidly, mainly because of its primary resistance to many antibiotics. The aim of the study was to characterize a postantibiotic effect (PAE) of chosen aminoglycosides and their influence on some biological properties of clinical isolates of S. maltophilia. The PAE was detected using suprainhibitory concentrations of 2x and 4x minimal inhibitory concentration (MIC) of amikacin, netilmicin and tobramycin at 37 °C in Miiller-Hinton broth for 24 h. The surface hydrophobicity of S. maltophilia cells was determined by adherence to xylen and salt aggregation test. Further, motility and production of lipase in strains tested was evaluated as well. The longest PAE - on the average 2 h has been induced by netilmicin on the strain No. 5 777. The infuence of suprainhibitory concentrations of aminoglycosides tested on the surface hydrophobicity and motility of both strains was not very apparend. The production of lipase was inhibited by netilimcin at 4x MIC level at the strain No. 27 823. The effects of suprainhibitory concentrations of aminoglycosides on S. maltophilia were generally lower in comparison to other gramnegative bacteria.
- MeSH
- Ampicillin therapeutic use MeSH
- Anti-Bacterial Agents therapeutic use MeSH
- Bacteria isolation & purification drug effects MeSH
- Bacterial Infections drug therapy microbiology MeSH
- Child MeSH
- Infant MeSH
- Humans MeSH
- Infant, Newborn, Diseases drug therapy microbiology MeSH
- Netilmicin therapeutic use MeSH
- Infant, Newborn MeSH
- Check Tag
- Child MeSH
- Infant MeSH
- Humans MeSH
- Infant, Newborn MeSH
- MeSH
- Netilmicin pharmacology MeSH
- Norfloxacin pharmacology MeSH
- Salmonella drug effects MeSH
- Publication type
- Comparative Study MeSH
- MeSH
- Medical Oncology MeSH
- Humans MeSH
- Netilmicin administration & dosage blood MeSH
- Drug-Related Side Effects and Adverse Reactions MeSH
- Patients MeSH
- Check Tag
- Humans MeSH
- Male MeSH
- Female MeSH
- Publication type
- Comparative Study MeSH
