Ciprofloxacin Concentrations 100-Fold Lower than the MIC Can Select for Ciprofloxacin Resistance in Neisseria subflava: An In Vitro Study
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Published:2024-06-14
Issue:6
Volume:13
Page:560
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ISSN:2079-6382
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Container-title:Antibiotics
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language:en
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Short-container-title:Antibiotics
Author:
Gestels Zina1, Abdellati Saïd2ORCID, Kenyon Chris13ORCID, Manoharan-Basil Sheeba Santhini1ORCID
Affiliation:
1. Sexually Transmitted Infections Unit, Department of Clinical Sciences, Institute of Tropical Medicine, 2000 Antwerp, Belgium 2. Clinical and Reference Laboratory, Department of Clinical Sciences, Institute of Tropical Medicine, 2000 Antwerp, Belgium 3. Division of Infectious Diseases and HIV Medicine, University of Cape Town, Cape Town 7700, South Africa
Abstract
Neisseria gonorrhoeae can acquire antimicrobial resistance (AMR) through horizontal gene transfer (HGT) from other Neisseria spp. such as commensals like Neisseria subflava. Low doses of antimicrobials in food could select for AMR in N. subflava, which could then be transferred to N. gonorrhoeae. In this study, we aimed to determine the lowest concentration of ciprofloxacin that can induce ciprofloxacin resistance (minimum selection concentration—MSC) in a N. subflava isolate (ID-Co000790/2, a clinical isolate collected from a previous community study conducted at ITM). In this study, Neisseria subflava was serially passaged on gonococcal (GC) medium agar plates containing ciprofloxacin concentrations ranging from 1:100 to 1:10,000 below its ciprofloxacin MIC (0.006 µg/mL) for 6 days. After 6 days of serial passaging at ciprofloxacin concentrations of 1/100th of the MIC, 24 colonies emerged on the plate containing 0.06 µg/mL ciprofloxacin, which corresponds to the EUCAST breakpoint for N. gonorrhoeae. Their ciprofloxacin MICs were between 0.19 to 0.25 µg/mL, and whole genome sequencing revealed a missense mutation T91I in the gyrA gene, which has previously been found to cause reduced susceptibility to fluoroquinolones. The N. subflava MSCde novo was determined to be 0.06 ng/mL (0.00006 µg/mL), which is 100×-fold lower than the ciprofloxacin MIC. The implications of this finding are that the low concentrations of fluoroquinolones found in certain environmental samples, such as soil, river water, and even the food we eat, may be able to select for ciprofloxacin resistance in N. subflava.
Funder
SOFI 2021 grant—“PReventing the Emergence of untreatable STIs via radical Prevention”
Reference42 articles.
1. Unemo, M., del Rio, C., and Shafer, W.M. (2016). Antimicrobial Resistance Expressed by Neisseria gonorrhoeae: A Major Global Public Health Problem in the 21st Century. Microbiol. Spectr., 4. 2. Gullberg, E., Cao, S., Berg, O.G., Ilbäck, C., Sandegren, L., Hughes, D., and Andersson, D.I. (2011). Selection of Resistant Bacteria at Very Low Antibiotic Concentrations. PLOS Pathog., 7. 3. Selection of a multidrug resistance plasmid by sublethal levels of antibiotics and heavy metals;Gullberg;mBio,2014 4. González, N., Abdellati, S., De Baetselier, I., Laumen, J.G.E., Van Dijck, C., de Block, T., Manoharan-Basil, S.S., and Kenyon, C. (2022). Ciprofloxacin Concentrations 1/1000th the MIC Can Select for Antimicrobial Resistance in N. gonorrhoeae—Important Implications for Maximum Residue Limits in Food. Antibiotics, 11. 5. EMEA (1998). Enrofloxacin (Extension to Sheep, Rabbits, and Lactating Cows), EMEA. Summary Report.
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