Research Articles >
College of Science >
Please use this identifier to cite or link to this item:
|Title: ||Chromosomal and plasmid-mediated fluoroquinolone resistance in human Salmonella enterica infection in Ghana|
|Authors: ||Acheampong, Godfred|
Sylverken, A. A.
|Keywords: ||Fluoroquinolone resistance|
|Issue Date: ||2019|
|Publisher: ||BMC Infectious Diseases|
|Citation: ||BMC Infectious Diseases|
|Abstract: ||Background: Salmonella infection poses significant public health threat globally, especially in resource-limited
countries. Emergence and spread of antibiotic resistant strains to fluoroquinolones have led to treatment failures
and increased mortality in Salmonella infection. However, there is dearth of information regarding mechanisms of
resistance to fluoroquinolones in Ghana. This study therefore sought to identify chromosomal mutations and
plasmid-mediated resistance as possible mechanisms of fluoroquinolone resistance from clinical isolates in Ghana.
Methods: This was a retrospective study of archived isolates biobanked at Kumasi Centre for Collaborative Research
in Tropical Medicine, Ghana. Isolates were obtained from blood, stool and oropharynx samples at two hospitals,
between May, 2016 and January, 2018. Salmonella identification was done using standard microbiological protocols
and antibiotic susceptibility testing performed by Kirby-Bauer disc diffusion method. Isolates with intermediate
susceptibility and/or resistance to nalidixic acid and/or ciprofloxacin were selected and examined for chromosomal
mutations by Sanger sequencing and plasmid-mediated resistance by PCR.
Results: Of 133 biobanked isolates cultured, 68 (51.1%) and 16 (12%) were identified as Salmonella Typhi and nontyphoidal Salmonella (NTS), respectively. Sequence analysis of gyrA gene revealed the presence of 5 different
nonsynonymous mutations, with the most frequent mutation (Ile203Ser) occurring in 12 out of 13 isolates tested.
Gyrase B (gyrB) gene had 1 nonsynonymous mutation in 3 out of 13 isolates, substituting phenylalanine with leucine at
codon 601 (Phe601Leu). No mutation was observed in parC and parE genes. Two NTS isolates were found to harbour
qnrS plasmid-mediated resistant gene of molecular size 550 bp with high ciprofloxacin MIC of 0.5 μg/ml.
Conclusion: This study reports for the first time in Ghana plasmid-mediated fluoroquinolone resistant gene qnrS in
Salmonella clinical isolates. Nonsynonymous mutations of gyrA and gyrB genes likely to confer Salmonella reduced
susceptibility to ciprofloxacin were also reported.|
|Description: ||This article is published in BMC Infectious Diseases and also available at
|Appears in Collections:||College of Science|
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.