Trimethoprim-sulfamethoxazole (SXT) is the preferable treatment option of the infections caused by Achromobacter spp. Our study aimed to analyze the SXT resistance of 98 Achromobacter spp. isolates from pediatric patients, among which 33 isolates were SXT-resistant. The presence of intI1 was screened by PCR and genome sequence analyses. The intI1 gene was detected in 10 of SXT-resistant isolates that had shorter intI1 PCR fragments named intI1S. Structural changes in intI1S were confirmed by genome sequencing and analyses which revealed 86 amino acids deletion in IntI1S protein compared to canonical IntI1 protein. All IntI1S isolates were of non-CF origin. Pan-genome analysis of intI1S bearing A. xylosoxidans isolates comprised 9052 genes, with the core genome consisting of 5455 protein-coding genes. Results in this study indicate that IntI1S isolates were derived from clinical settings and that cystic fibrosis (CF) patients were potential reservoirs for healthcare-associated infections that occurred in non-CF patients.

• MeSH
• Achromobacter denitrificans * genetika   MeSH
• Achromobacter * MeSH
• antibakteriální látky terapeutické užití   MeSH
• cystická fibróza * MeSH
• dítě MeSH
• genomika MeSH
• gramnegativní bakteriální infekce * MeSH
• integrasy terapeutické užití   MeSH
• integrony genetika   MeSH
• kombinace léků trimethoprim a sulfamethoxazol MeSH
• lidé MeSH
• mikrobiální testy citlivosti MeSH
• Check Tag
• dítě MeSH
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Srbsko MeSH

The aim of this study was to evaluate the contribution of plasmid-mediated genes and efflux to fluoroquinolone resistance in collection of Achromobacter spp. gathered during a 3-year period. Susceptibility to ciprofloxacin and levofloxacin was tested by disk diffusion and microdilution tests for a collection of 98 Achromobacter spp. clinical isolates. Identification of fluoroquinolone-resistant isolates was performed by sequencing and phylogenetic analyses of the nrdA gene. Genetic relatedness among resistant isolates was determined by pulsed-field gel electrophoresis (PFGE) analysis. The influence of an H+ conductor cyanide m-chlorophenyl hydrazone (CCCP) and a resistance-nodulation-division-type efflux pump inhibitor phenylalanine-arginine beta-naphthylamide (PAβN) on minimal inhibitory concentration (MIC) value was evaluated by broth microdilution. The presence of the plasmid-mediated qnrA, qnrB, qnrC, qnrS, and aac-(6')-Ib-cr genes was investigated by PCR and sequencing. Achromobacter spp. isolates that were resistant or intermediately resistant to fluoroquinolones in disk diffusion tests (44/98) were subjected to microdilution. As a result, 20/98 isolates were confirmed to be resistant to ciprofloxacin while 10/98 was resistant to levofloxacin. CCCP decreased twofold MIC value for ciprofloxacin in six isolates and more than 16 times in one isolate, while MIC value for levofloxacin was decreased in all isolates (twofold to more than eightfold). Fluoroquinolone-resistant isolates were identified as A. xylosoxidans with the nrdA gene sequencing. PFGE revealed that resistant isolates belonged to seven different genotypes. Ten isolates belonging to four genotypes were positive for the aac-(6')-Ib-cr gene. Although resistance to fluoroquinolones was not widespread among analyzed isolates, detected contribution of efflux pumps and the presence of the aac-(6')-Ib-cr gene present a platform for emergence of more resistant strains.

• MeSH
• Achromobacter denitrificans klasifikace   účinky léků   genetika   izolace a purifikace   MeSH
• antibakteriální látky farmakologie   MeSH
• bakteriální geny * genetika   MeSH
• bakteriální léková rezistence genetika   MeSH
• fluorochinolony farmakologie   MeSH
• fylogeneze MeSH
• genotyp MeSH
• gramnegativní bakteriální infekce mikrobiologie   MeSH
• lidé MeSH
• mikrobiální testy citlivosti MeSH
• plazmidy genetika   MeSH
• polymerázová řetězová reakce MeSH
• pulzní gelová elektroforéza MeSH
• sekvenční analýza DNA MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Srbsko MeSH