Fluoroquinolone-resistance mechanisms and molecular epidemiology of ciprofloxacin-resistant Klebsiella pneumoniae isolates in Iran.
Folia Microbiol (Praha)
; 68(4): 633-644, 2023 Aug.
Article
em En
| MEDLINE
| ID: mdl-36870040
ABSTRACT
Klebsiella pneumoniae is an important cause of nosocomial infections and displays increasing resistance to fluoroquinolones (FQ). This study surveyed the mechanisms of FQ resistance and molecular typing of K. pneumoniae isolates from intensive care units patients in Tehran, Iran. A total of 48 ciprofloxacin (CIP) resistant K. pneumoniae isolates from urine samples were included in this study. Broth microdilution assays revealed high-level CIP resistance (MIC > 32 µg/mL) in 31.25% of the isolates. Plasmid-mediated quinolone resistance genes were detected in 41 (85.4%) isolates. Among which, qnrS (41.67%) was the most prevalent followed by qnrD (35.42%), qnrB (27.1%), qnrA (25%), qepA (22.9%), aac(6')-Ib-cr (20.83%), and qnrC (6.25%). Target site mutations (gyrA and parC) were assessed using PCR and sequencing on all isolates. A single mutation in gyrA (S83I) was found in 13 (27.1%) isolates and two isolates harbored six simultaneous mutations. Fourteen isolates (29.2%) had mutations in parC and S129A and A141V mutations were the most prevalent. Real time PCR showed an increase in the expression level of acrB and oqxB efflux genes in 68.75 and 29.16% isolates, respectively. Enterobacterial repetitive intergenic consensus (ERIC)-PCR revealed 14 genotypes and 11 of them were classified by multilocus sequence typing (MLST) into 11 different sequence types belonging to seven clonal complexes and two singletons, most of them have not been reported in Iran yet. We are concerned about the spread of these clones throughout our country. Most FQ resistance mechanisms were detected among our isolates. However, target site mutation had the greatest effect on CIP resistance among our isolates.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Ciprofloxacina
/
Fluoroquinolonas
Tipo de estudo:
Screening_studies
Limite:
Humans
País/Região como assunto:
Asia
Idioma:
En
Revista:
Folia Microbiol (Praha)
Ano de publicação:
2023
Tipo de documento:
Article
País de afiliação:
Irã