Carriage of plasmid-mediated qnr determinants and quinolone efflux pump (qepA) by ciprofloxacin-resistant bacteria recovered from Urinary Tract Infection (UTI) samples

Abstract

Background Bacterial resistance to commonly-used antibiotics has been on the increase especially in the clinical settings. This study focused on the detection of plasmid-mediated quinolone resistance (PMQR) determinants in ciprofloxacin-resistant bacteria recovered from Urinary Tract Infection (UTI) samples. Results Already characterized isolates from urine samples of UTI-diagnosed in- and out- patients were obtained from the culture pool of the Department of Medical Microbiology and Parasitology, University College Hospital (UCH), Ibadan, Nigeria. A total of seventy-three ciprofloxacin-resistant isolates were used in this study. Of the 73 UTI isolates, 43 carried at least one of the four PMQR genes targeted and they belonged to eight bacterial genera namely: Escherichia (25), Klebsiella (10), Pseudomonas (2), Proteus (2) and one isolate each belonging to Enterobacter, Acinetobacter, Citrobacter and Salmonella genera. qnrA was detected in 10.9% (8/73) of the isolates while the occurrence of qnrB and qnrS was 32.9% (24/73) and 20.5% (15/73), respectively. The quinolone efflux pump (qepA) was detected in 9/73 (12.3%) of the isolates. Thirty of the isolates carried only one PMQR gene, while thirteen carried two PMQR genes. There was no carriage of more than two PMQR genes in the forty-three isolates from which PMQR genes were detected. Conclusion This study reports the carriage of PMQR determinants by eight of the nine Gram-negative bacterial genera from urinary sources in patients attending the University College Hospital, Ibadan over the four-month period of study. This is quite worrisome as it suggests a high contribution of UTI cases to the burden of quinolone resistance. There is a need for more studies of this nature in other hospitals in Nigeria, to develop a database on the contribution of UTI cases to quinolone resistance.

Plasmid-mediated quinolone resistance genes detected in Ciprofloxacin non-susceptible Escherichia coli and Klebsiella isolated from children under five years at hospital discharge, Kenya

“…The qepA gene , one of the most recently identified PMQR determinants, has been associated with decreased susceptibility to fluoroquinolones and increased MIC levels [ 13 ]. This determinant was detected in (16/188, 8.5%) E. coli isolates which was slightly lower compared to previous studies in Nigeria (18.5%) and Sierra Leon (23%) [ 28 , 30 ]. DNA sequencing confirmed the existence of the qepA gene among E. coli isolates in Kenya with F95L and V134I amino acid substitution consistent with amino acid substitution reported in the qepA4 allele [ 40 ].…”

“…One of the six PMQR genes ( qepA ) had not previously been detected in clinical isolates in Kenya. The qepA gene has been reported in very few studies within the SSA region: Chad, Malawi, Egypt, Sierra Leon, and Nigeria [ 26 – 30 ]. Other PMQR determinants that have been identified in Kenya are aac(6’)-lb-cr , qnrB , qnrS in E. coli [ 31 ], qnrS, and oqxAB in K.pneumoniae [ 32 , 33 ].…”

Multiple PMQR genes including the rare qepA detected in Ciprofloxacin non-susceptible Escherichia coli and Klebsiella isolated from children under five years at hospital discharge, Kenya.

“…The qepA gene, one of the most recently identi ed PMQR determinants, has been associated with decreased susceptibility to uoroquinolones and increased MIC levels [24]. This determinant was detected in (16/188, 8.5%) E. coli isolates which was slightly lower compared to previous studies in Nigeria (18.5%) and Sierra Leon (23%) [27,29]. DNA sequencing con rmed the existence of the qepA gene among E. coli isolates in Kenya with F95L and V134I amino acid substitution consistent with amino acid substitution reported in the qepA4 allele [42].…”

“…One of the six PMQR genes (qepA) had not previously been detected in clinical isolates in Kenya. The qepA gene has been reported in very few studies within the SSA region: Chad, Malawi, Egypt, Sierra Leon, and Nigeria [25][26][27][28][29]. Other PMQR determinants that have been identi ed in Kenya are aac(6')-lb-cr, qnrB, qnrS in E. coli [30,31], qnrS, and oqxAB in K.pneumoniae [32,33].…”

Effect of Carbonyl Cyanide M-chlorophenylhydrazone on Ciprofloxacin Resistance and Biofilm Formation in Hospital-acquired Uropathogenic Escherichia coli and Klebsiella pneumoniae

“…14 Also efflux pump qepA was detected in 12.3% of CIP resistant bacteria isolated from UTI. 33 Higher rate of oqxAB was detected in K. pneumoniae but it was not detected in E. coli. Moreover, QepA was not detected in any of Enterobacteriaceae species in a study conducted in South Africa.…”