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Wang H, Zhang L. Susceptibility evaluation and PK/PD integration of tulathromycin against Actinobacillus pleuropneumoniae during the mutant selection window. Front Vet Sci 2024; 11:1407907. [PMID: 39051006 PMCID: PMC11267949 DOI: 10.3389/fvets.2024.1407907] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2024] [Accepted: 06/13/2024] [Indexed: 07/27/2024] Open
Abstract
Introduction Actinobacillus pleuropneumoniae (APP) is a serious pathogen that affects the development of livestock breeding. Due to excessive use of antimicrobial drugs, many multidrug-resistant bacteria have emerged and spread, which have threatened the livestock industry. Therefore, we established a peristaltic pump infection model (PPIM) to evaluate the susceptibility change and pharmacokinetic/pharmacodynamic (PK/PD) integration of tulathromycin against APP during the mutant selection window (MSW) for preventing the emergence of mutant-resistant bacteria. Methods The 99% minimum inhibitory concentration (MIC99) and mutant prevention concentration (MPC) of tulathromycin against APP were measured using the agar-plate method. After the model of dynamic infection had been established based on tulathromycin data in lungs, different dosages were administered to make the drug concentrations located in different parts of the MSW. The population and sensitivity of APP were monitored. Tulathromycin concentrations were measured by high-performance liquid chromatography-tandem mass spectrometry. Finally, a sigmoid Emax model was used to analyze the relationships between PK/PD parameters and antibacterial effects. Results and discussion The values of MIC, MIC99, and MPC of tulathromycin against APP were 2, 1.4, and 44.8 μg/mL, respectively. The PPIM was stable. An elimination effect without regrowth was observed at 5.6 to 44.8 μg/mL (-4.48 to -7.05 Log10 CFU/mL, respectively). The MIC of APP increased 32-fold at 8 MIC99. AUC168 h/MIC99 had the best fit with the antibacterial effect (R 2 = 0.9867). The AUC168 h/MIC99 required to achieve bacteriostatic, bactericidal, and clearance effects were 1.80, 87.42, and 198 h, respectively. Our results could provide guidance for the clinical application of tulathromycin to treat APP infection and avoid the generation of drug-resistant bacteria.
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Affiliation(s)
- Hongjuan Wang
- College of Animal Science and Veterinary Medicine, Henan Institute of Science and Technology, Xinxiang, China
- Institute of Traditional Chinese Veterinary Medicine, College of Veterinary Medicine, Gansu Agricultural University, Lanzhou, China
| | - Longfei Zhang
- Institute of Traditional Chinese Veterinary Medicine, College of Veterinary Medicine, Gansu Agricultural University, Lanzhou, China
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Wang H, Liao C, Ding K, Zhang L, Wang L. Evaluation the kill rate and mutant selection window of danofloxacin against Actinobacillus pleuropneumoniae in a peristaltic pump model. BMC Vet Res 2024; 20:241. [PMID: 38831324 PMCID: PMC11145865 DOI: 10.1186/s12917-024-04016-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2023] [Accepted: 04/12/2024] [Indexed: 06/05/2024] Open
Abstract
BACKGROUND Actinobacillus pleuropneumoniae is a serious pathogen in pigs. The abundant application of antibiotics has resulted in the gradual emergence of drugresistant bacteria, which has seriously affected treatment of disease. To aid measures to prevent the emergence and spread of drug-resistant bacteria, herein, the kill rate and mutant selection window (MSW) of danofloxacin (DAN) against A. pleuropneumoniae were evaluated. METHODS For the kill rate study, the minimum inhibitory concentration (MIC) was tested using the micro dilution broth method and time-killing curves of DAN against A. pleuropneumoniae grown in tryptic soy broth (TSB) at a series drug concentrations (from 0 to 64 MIC) were constructed. The relationships between the kill rate and drug concentrations were analyzed using a Sigmoid Emax model during different time periods. For the MSW study, the MIC99 (the lowest concentration that inhibited the growth of the bacteria by ≥ 99%) and mutant prevention concentration (MPC) of DAN against A. pleuropneumoniae were measured using the agar plate method. Then, a peristaltic pump infection model was established to simulate the dynamic changes of DAN concentrations in pig lungs. The changes in number and sensitivity of A. pleuropneumoniae were measured. The relationships between pharmacokinetic/pharmacodynamic parameters and the antibacterial effect were analyzed using the Sigmoid Emax model. RESULTS In kill rate study, the MIC of DAN against A. pleuropneumoniae was 0.016 µg/mL. According to the kill rate, DAN exhibited concentration-dependent antibacterial activity against A. pleuropneumoniae. A bactericidal effect was observed when the DAN concentration reached 4-8 MIC. The kill rate increased constantly with the increase in DAN concentration, with a maximum value of 3.23 Log10 colony forming units (CFU)/mL/h during the 0-1 h period. When the drug concentration was in the middle part of the MSW, drugresistant bacteria might be induced. Therefore, the dosage should be avoided to produce a mean value of AUC24h/MIC99 (between 31.29 and 62.59 h. The values of AUC24h/MIC99 to achieve bacteriostatic, bactericidal, and eradication effects were 9.46, 25.14, and > 62.59 h, respectively. CONCLUSION These kill rate and MSW results will provide valuable guidance for the use of DAN to treat A. pleuropneumoniae infections.
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Affiliation(s)
- Hongjuan Wang
- College of Animal Science and Veterinary Medicine, Henan Institute of Science and Technology, Xinxiang, 453003, China
- Institute of Traditional Chinese Veterinary Medicine, College of Veterinary Medicine, Gansu Agricultural University, Lanzhou, 730070, China
| | - Chengshui Liao
- College of Animal Science and Veterinary Medicine, Henan Institute of Science and Technology, Xinxiang, 453003, China
- The Key Lab of Veterinary Biological Products, Henan University of Science and Technology, Luoyang, 471000, China
| | - Ke Ding
- College of Animal Science and Veterinary Medicine, Henan Institute of Science and Technology, Xinxiang, 453003, China
- Laboratory of Functional Microbiology and Animal Health, Henan University of Science and Technology, Luoyang, 471023, China
| | - Longfei Zhang
- College of Animal Science and Veterinary Medicine, Henan Institute of Science and Technology, Xinxiang, 453003, China.
| | - Lei Wang
- College of Animal Science and Veterinary Medicine, Henan Institute of Science and Technology, Xinxiang, 453003, China.
- Institute of Farmland Irrigation, Chinese Academy of Agricultural Sciences, Xinxiang, 453003, China.
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Zhang F, Liu F, Sheng X, Liu Q, Cui L, Cao Z, Hu T, Li D, Dai M. Bacitracin-resistant Staphylococcus aureus induced in chicken gut and in vitro under bacitracin exposure. Microb Pathog 2024; 191:106666. [PMID: 38685360 DOI: 10.1016/j.micpath.2024.106666] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2024] [Revised: 04/13/2024] [Accepted: 04/26/2024] [Indexed: 05/02/2024]
Abstract
It is common knowledge that prolonged and excessive use of antibiotics can lead to antimicrobial resistance. However, the characteristics and mechanism of resistant-bacteria induced by clinically recommended and prophylactic dose drugs remain largely unclear. This study aimed to observe the trends of drug resistance of the bacitracin-susceptible Staphylococcus aureus strain FS127 under exposure to bacitracin (BAC), which were induced in vitro and in chicken gut. Antimicrobial susceptibility testing was used to detect the susceptibility of S. aureus induced in vitro and in the chicken gut to gentamicin, chloramphenicol, tetracycline, doxycycline, penicillin and chloramphenicol. The research results showed that bacitracin could induce drug resistance in S. aureus both in vitro and in vivo. The bacitracin-resistance rate of S. aureus isolated from chicken gut was positively correlated with the dose and time of bacitracin administration. The findings revealed that bacitracin-resistant S. aureus induced in vivo had enhanced susceptibility to chloramphenicol but no such change in vitro. Meanwhile, RT-qPCR assay was used to detect the expression levels of vraD, braD, braR and bacA in typical strains with different bacitracin-resistance levels. It was found that BacA may play a key role in the bacitracin resistance of S. aureus. In conclusion, this work reveals the characteristics and mechanism of bacitracin-resistant S. aureus induced by bacitracin in vivo and in vitro respectively.
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Affiliation(s)
- Fan Zhang
- The Cooperative Innovation Center for Sustainable Pig Production, Huazhong Agricultural University, Wuhan, 430070, China; MOA Key Laboratory of Food Safety Evaluation/National Reference Laboratory of Veterinary Drug Residue (HZAU), Huazhong Agricultural University, Wuhan, 430070, China
| | - Fangjia Liu
- The Cooperative Innovation Center for Sustainable Pig Production, Huazhong Agricultural University, Wuhan, 430070, China; MOA Key Laboratory of Food Safety Evaluation/National Reference Laboratory of Veterinary Drug Residue (HZAU), Huazhong Agricultural University, Wuhan, 430070, China
| | - Xijing Sheng
- The Cooperative Innovation Center for Sustainable Pig Production, Huazhong Agricultural University, Wuhan, 430070, China; MOA Key Laboratory of Food Safety Evaluation/National Reference Laboratory of Veterinary Drug Residue (HZAU), Huazhong Agricultural University, Wuhan, 430070, China
| | - Quan Liu
- The Cooperative Innovation Center for Sustainable Pig Production, Huazhong Agricultural University, Wuhan, 430070, China; MOA Key Laboratory of Food Safety Evaluation/National Reference Laboratory of Veterinary Drug Residue (HZAU), Huazhong Agricultural University, Wuhan, 430070, China
| | - Luqing Cui
- The Cooperative Innovation Center for Sustainable Pig Production, Huazhong Agricultural University, Wuhan, 430070, China; MOA Key Laboratory of Food Safety Evaluation/National Reference Laboratory of Veterinary Drug Residue (HZAU), Huazhong Agricultural University, Wuhan, 430070, China
| | - Zhengzheng Cao
- The Cooperative Innovation Center for Sustainable Pig Production, Huazhong Agricultural University, Wuhan, 430070, China; MOA Key Laboratory of Food Safety Evaluation/National Reference Laboratory of Veterinary Drug Residue (HZAU), Huazhong Agricultural University, Wuhan, 430070, China
| | - Tianyu Hu
- The Cooperative Innovation Center for Sustainable Pig Production, Huazhong Agricultural University, Wuhan, 430070, China; MOA Key Laboratory of Food Safety Evaluation/National Reference Laboratory of Veterinary Drug Residue (HZAU), Huazhong Agricultural University, Wuhan, 430070, China
| | - Donghua Li
- The Cooperative Innovation Center for Sustainable Pig Production, Huazhong Agricultural University, Wuhan, 430070, China; MOA Key Laboratory of Food Safety Evaluation/National Reference Laboratory of Veterinary Drug Residue (HZAU), Huazhong Agricultural University, Wuhan, 430070, China
| | - Menghong Dai
- The Cooperative Innovation Center for Sustainable Pig Production, Huazhong Agricultural University, Wuhan, 430070, China; MOA Key Laboratory of Food Safety Evaluation/National Reference Laboratory of Veterinary Drug Residue (HZAU), Huazhong Agricultural University, Wuhan, 430070, China.
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Strukova EN, Golikova MV, Dovzhenko SA, Kobrin MB, Zinner SH. Pharmacodynamics of Doripenem Alone and in Combination with Relebactam in an In Vitro Hollow-Fiber Dynamic Model: Emergence of Resistance of Carbapenemase-Producing Klebsiella pneumoniae and the Inoculum Effect. Antibiotics (Basel) 2023; 12:1705. [PMID: 38136739 PMCID: PMC10741200 DOI: 10.3390/antibiotics12121705] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2023] [Revised: 12/01/2023] [Accepted: 12/05/2023] [Indexed: 12/24/2023] Open
Abstract
The emergence of bacteria resistant to beta-lactam/beta-lactamase inhibitor combinations is insufficiently studied, wherein the role of the inoculum effect (IE) in decreased efficacy is unclear. To address these issues, 5-day treatments with doripenem and doripenem/relebactam combination at different ratios of the agents were simulated in a hollow-fiber dynamic model against carbapenemase-producing K. pneumoniae at standard and high inocula. Minimal inhibitory concentrations (MICs) of doripenem alone and in the presence of relebactam at two inocula were determined. Combination MICs were tested using traditional (fixed relebactam concentration) and pharmacokinetic-based approach (fixed doripenem-to-relebactam concentration ratio equal to the therapeutic 24-h area under the concentration-time curve (AUC) ratio). In all experiments, resistant subpopulations were noted, but combined simulations reduced their numbers. With doripenem, the IE was apparent for both K. pneumoniae isolates in combined treatments for one strain. The pharmacokinetic-based approach to combination MIC estimation compared to traditional showed stronger correlation between DOSE/MIC and emergence of resistance. These results support (1) the constraint of relebactam combined with doripenem against the emergence of resistance and IE; (2) the applicability of a pharmacokinetic-based approach to estimate carbapenem MICs in the presence of an inhibitor to predict the IE and to describe the patterns of resistance occurrence.
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Affiliation(s)
- Elena N. Strukova
- Department of Pharmacokinetics & Pharmacodynamics, Gause Institute of New Antibiotics, 11 Bolshaya Pirogovskaya Street, 119021 Moscow, Russia; (E.N.S.); (S.A.D.); (M.B.K.)
| | - Maria V. Golikova
- Department of Pharmacokinetics & Pharmacodynamics, Gause Institute of New Antibiotics, 11 Bolshaya Pirogovskaya Street, 119021 Moscow, Russia; (E.N.S.); (S.A.D.); (M.B.K.)
| | - Svetlana A. Dovzhenko
- Department of Pharmacokinetics & Pharmacodynamics, Gause Institute of New Antibiotics, 11 Bolshaya Pirogovskaya Street, 119021 Moscow, Russia; (E.N.S.); (S.A.D.); (M.B.K.)
| | - Mikhail B. Kobrin
- Department of Pharmacokinetics & Pharmacodynamics, Gause Institute of New Antibiotics, 11 Bolshaya Pirogovskaya Street, 119021 Moscow, Russia; (E.N.S.); (S.A.D.); (M.B.K.)
| | - Stephen H. Zinner
- Harvard Medical School, Department of Medicine, Mount Auburn Hospital, 330 Mount Auburn St., Cambridge, MA 02138, USA;
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Zhang L, Wang H, Bai Y, Wang L, Bai Y, Hu J. Evaluation of the mutant selection window of danofloxacin against Actinobacillus pleuropneumoniae in an in vitro dynamic model. Front Vet Sci 2023; 10:1107608. [PMID: 36793382 PMCID: PMC9923107 DOI: 10.3389/fvets.2023.1107608] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2022] [Accepted: 01/11/2023] [Indexed: 01/31/2023] Open
Abstract
Introduction The rapid emergence and widespread spread of multidrug-resistant bacteria is a serious threat to the health of humans and animals. The pharmacokinetic/pharmacodynamic (PK/PD) integration model based on mutant selection window (MSW) theory is an important method to optimize the dosage regimen to prevent the emergence and spread of drug-resistant bacteria. Actinobacillus pleuropneumoniae (AP) is a pathogen that can cause pleuropneumonia in pigs. Methods We employed an in vitro dynamic infection model (DIM) to study the prevention of drug-resistant mutations of danofloxacin against AP. A peristaltic pump was applied to establish an in vitro DIM to simulate the PK of danofloxacin in plasma, and to study the MSW of danofloxacin against AP. A peristaltic-pump in vitro infection model was established to simulate dynamic changes in the danofloxacin concentration in pig plasma. PK and PD data were obtained. Then, the relationship between PK/PD parameters and antibacterial activity was analyzed by the sigmoid Emax model. Results and discussion The area under the curve during 24 h/ the minimum concentration that inhibits colony formation by 99% (AUC24h/MIC99) had the best-fitting relationship with antibacterial activity. The AUC24h/MIC99 values for a bacteriostatic effect, bactericidal effect, and eradication effect were 2.68, 33.67, and 71.58 h, respectively. We hope these results can provide valuable guidance when using danofloxacin to treat AP infection.
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Affiliation(s)
- Longfei Zhang
- College of Animal Science and Veterinary Medicine of Henan Institute of Science and Technology, Xinxiang, China
| | - Hongjuan Wang
- College of Animal Science and Veterinary Medicine of Henan Institute of Science and Technology, Xinxiang, China
| | - Yilin Bai
- School of Agricultural Sciences, Zhengzhou University, Zhengzhou, China
| | - Lei Wang
- College of Animal Science and Veterinary Medicine of Henan Institute of Science and Technology, Xinxiang, China,*Correspondence: Lei Wang ✉
| | - Yueyu Bai
- College of Animal Science and Veterinary Medicine of Henan Institute of Science and Technology, Xinxiang, China,School of Agricultural Sciences, Zhengzhou University, Zhengzhou, China,Yueyu Bai ✉
| | - Jianhe Hu
- College of Animal Science and Veterinary Medicine of Henan Institute of Science and Technology, Xinxiang, China,Jianhe Hu ✉
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Singh A, Zhao X, Drlica K. Fluoroquinolone heteroresistance, antimicrobial tolerance, and lethality enhancement. Front Cell Infect Microbiol 2022; 12:938032. [PMID: 36250047 PMCID: PMC9559723 DOI: 10.3389/fcimb.2022.938032] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2022] [Accepted: 07/21/2022] [Indexed: 11/13/2022] Open
Abstract
With tuberculosis, the emergence of fluoroquinolone resistance erodes the ability of treatment to interrupt the progression of MDR-TB to XDR-TB. One way to reduce the emergence of resistance is to identify heteroresistant infections in which subpopulations of resistant mutants are likely to expand and make the infections fully resistant: treatment modification can be instituted to suppress mutant enrichment. Rapid DNA-based detection methods exploit the finding that fluoroquinolone-resistant substitutions occur largely in a few codons of DNA gyrase. A second approach for restricting the emergence of resistance involves understanding fluoroquinolone lethality through studies of antimicrobial tolerance, a condition in which bacteria fail to be killed even though their growth is blocked by lethal agents. Studies with Escherichia coli guide work with Mycobacterium tuberculosis. Lethal action, which is mechanistically distinct from blocking growth, is associated with a surge in respiration and reactive oxygen species (ROS). Mutations in carbohydrate metabolism that attenuate ROS accumulation create pan-tolerance to antimicrobials, disinfectants, and environmental stressors. These observations indicate the existence of a general death pathway with respect to stressors. M. tuberculosis displays a variation on the death pathway idea, as stress-induced ROS is generated by NADH-mediated reductive stress rather than by respiration. A third approach, which emerges from lethality studies, uses a small molecule, N-acetyl cysteine, to artificially increase respiration and additional ROS accumulation. That enhances moxifloxacin lethality with M. tuberculosis in culture, during infection of cultured macrophages, and with infection of mice. Addition of ROS stimulators to fluoroquinolone treatment of tuberculosis constitutes a new direction for suppressing the transition of MDR-TB to XDR-TB.
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Affiliation(s)
- Amit Singh
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore, India
- Centre for Infectious Disease Research, Indian Institute of Science, Bangalore, India
- *Correspondence: Amit Singh, ; Karl Drlica,
| | - Xilin Zhao
- Public Health Research Institute and Department of Microbiology, Biochemistry and Molecular Genetics, New Jersey Medical School, Rutgers Biomedical and Health Sciences, Rutgers University, Newark, NJ, United States
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, Xiamen, China
| | - Karl Drlica
- Public Health Research Institute and Department of Microbiology, Biochemistry and Molecular Genetics, New Jersey Medical School, Rutgers Biomedical and Health Sciences, Rutgers University, Newark, NJ, United States
- *Correspondence: Amit Singh, ; Karl Drlica,
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Chen X, Han J, Wang S. Integrated evolutionary analysis reveals the resistance risk to antimicrobial peptides in Staphylococcus aureus. Food Control 2022. [DOI: 10.1016/j.foodcont.2022.108966] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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Nemonoxacin enhances antibacterial activity and anti-resistant mutation ability of vancomycin against methicillin-resistant Staphylococcus aureus in an in vitro dynamic pharmacokinetic/pharmacodynamic model. Antimicrob Agents Chemother 2021; 66:e0180021. [PMID: 34902266 DOI: 10.1128/aac.01800-21] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Reduced susceptibility and emergence of resistance to vancomycin in methicillin-resistant Staphylococcus aureus (MRSA) have led to the development of various vancomycin based combinations. Nemonoxacin is a novel nonfluorinated quinolone with antibacterial activity against MRSA. The present study aimed to investigate the effects of nemonoxacin on antibacterial activity and the anti-resistant mutation ability of vancomycin for MRSA and explore whether quinolone resistance genes are associated with a reduction in the vancomycin minimal inhibitory concentration (MIC) and mutant prevention concentration (MPC) when combined with nemonoxacin. Four isolates, all with a vancomycin MIC of 2 μg/mL, were used in a modified in vitro dynamic pharmacokinetic/pharmacodynamic model to investigate the effects of nemonoxacin on antibacterial activity (M04, M23 and M24) and anti-resistant mutation ability (M04, M23 and M25, all with MPC ≥19.2 μg/mL) of vancomycin. The mutation sites of gyrA, gyrB, parC, and parE of 55 clinical MRSA isolates were sequenced. We observed that in M04 and M23, the combination of vancomycin (1g q12h) and nemonoxacin (0.5g qd) showed a synergistic bactericidal activity and resistance enrichment suppression. All clinical isolates resistant to nemonoxacin harbored gyrA (S84→L) mutation; gyrA (S84→L) and parC (E84→K) mutations were the two independent risk factors for the unchanged vancomycin MPC in combination. Nemonoxacin enhances the bactericidal activity and suppresses resistance enrichment ability of vancomycin against MRSA with a MIC of 2 μg/mL. Our in vitro data support the combination of nemonoxacin and vancomycin for the treatment of MRSA infection with a high MIC.
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Reding C, Catalán P, Jansen G, Bergmiller T, Wood E, Rosenstiel P, Schulenburg H, Gudelj I, Beardmore R. The Antibiotic Dosage of Fastest Resistance Evolution: gene amplifications underpinning the inverted-U. Mol Biol Evol 2021; 38:3847-3863. [PMID: 33693929 PMCID: PMC8382913 DOI: 10.1093/molbev/msab025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
To determine the dosage at which antibiotic resistance evolution is most rapid, we treated Escherichia coli in vitro, deploying the antibiotic erythromycin at dosages ranging from zero to high. Adaptation was fastest just below erythromycin’s minimal inhibitory concentration (MIC) and genotype-phenotype correlations determined from whole genome sequencing revealed the molecular basis: simultaneous selection for copy number variation in three resistance mechanisms which exhibited an “inverted-U” pattern of dose-dependence, as did several insertion sequences and an integron. Many genes did not conform to this pattern, however, reflecting changes in selection as dose increased: putative media adaptation polymorphisms at zero antibiotic dosage gave way to drug target (ribosomal RNA operon) amplification at mid dosages whereas prophage-mediated drug efflux amplifications dominated at the highest dosages. All treatments exhibited E. coli increases in the copy number of efflux operons acrAB and emrE at rates that correlated with increases in population density. For strains where the inverted-U was no longer observed following the genetic manipulation of acrAB, it could be recovered by prolonging the antibiotic treatment at subMIC dosages.
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Affiliation(s)
- Carlos Reding
- Biosciences, College of Life and Environmental Sciences, University of Exeter, Exeter EX4 4QD, UK
| | - Pablo Catalán
- Biosciences, College of Life and Environmental Sciences, University of Exeter, Exeter EX4 4QD, UK.,Grupo Interdisciplinar de Sistemas Complejos (GISC), Departamento de Matemáticas, Universidad Carlos III, Madrid, Spain
| | | | | | - Emily Wood
- Biosciences, College of Life and Environmental Sciences, University of Exeter, Exeter EX4 4QD, UK
| | - Phillip Rosenstiel
- Institute of Clinical Molecular Biology (IKMB), CAU Kiel, Kiel 24105, Germany
| | - Hinrich Schulenburg
- Evolutionary Ecology and Genetics, Zoological Institute, CAU Kiel, Kiel 24118, Germany
| | - Ivana Gudelj
- Biosciences, College of Life and Environmental Sciences, University of Exeter, Exeter EX4 4QD, UK
| | - Robert Beardmore
- Biosciences, College of Life and Environmental Sciences, University of Exeter, Exeter EX4 4QD, UK
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Huang Z, Mao C, Wei Y, Gu X, Cai Q, Shen X, Ding H. Analysis of the mutant selection window and killing of Mycoplasma hyopneumoniae for doxycycline, tylosin, danofloxacin, tiamulin, and valnemulin. PLoS One 2020; 15:e0220350. [PMID: 32544163 PMCID: PMC7297357 DOI: 10.1371/journal.pone.0220350] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2019] [Accepted: 05/14/2020] [Indexed: 11/20/2022] Open
Abstract
Mycoplasma hyopneumoniae is the major pathogenic microorganism causing enzootic pneumonia in pigs. With increasing resistance of M. hyopneumoniae to conventional antibiotics, treatment is becoming complicated. Herein, we investigated the mutant selection window (MSW) of doxycycline, tylosin, danofloxacin, tiamulin, and valnemulin for treating the M. hyopneumoniae type strain (ATCC 25934) to determine the likelihood of promoting resistance with continued use of these antibiotics. Minimum inhibitory concentration (MIC) values against M. hyopneumoniae were determined for each antimicrobial agent based on microdilution broth and agar dilution methods (bacterial numbers ranged from 105 colony-forming units (CFU)/mL to 109 CFU/mL). The minimal concentration inhibiting colony formation by 99% (MIC99) and the mutant prevention concentration (MPC) were determined by the agar dilution method with three inoculum sizes. Antimicrobial killing was determined based on MIC99 and MPC values for all five agents. MIC values ranged from 0.001 to 0.25 μg/mL based on the microdilution broth method, and from 0.008 to 1.0 μg/mL based on the agar dilution method. MPC values ranged from 0.0016 to 10.24 μg/mL. MPC/MIC99 values were ordered tylosin > doxycycline > danofloxacin > tiamulin > valnemulin. MPC achieved better bactericidal action than MIC99. Based on pharmacodynamic analyses, danofloxacin, tylosin, and doxycycline are more likely to select resistant mutants than tiamulin and valnemulin.
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Affiliation(s)
- Zilong Huang
- Guangdong Key Laboratory for Veterinary Drug Development and Safety Evaluation, South China Agricultural University, Guangzhou, China
| | - Chunxiao Mao
- Guangdong Key Laboratory for Veterinary Drug Development and Safety Evaluation, South China Agricultural University, Guangzhou, China
| | - Yanzhe Wei
- Guangdong Key Laboratory for Veterinary Drug Development and Safety Evaluation, South China Agricultural University, Guangzhou, China
| | - Xiaoyan Gu
- Guangdong Key Laboratory for Veterinary Drug Development and Safety Evaluation, South China Agricultural University, Guangzhou, China
| | - Qinren Cai
- Technical Center for Inspection and Quarantine, Zhuhai Entry-Exit Inspection and Quarantine Bureau, Zhuhai, China
| | - Xiangguang Shen
- Guangdong Key Laboratory for Veterinary Drug Development and Safety Evaluation, South China Agricultural University, Guangzhou, China
| | - Huanzhong Ding
- Guangdong Key Laboratory for Veterinary Drug Development and Safety Evaluation, South China Agricultural University, Guangzhou, China
- * E-mail:
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Acosta MM, Bram JT, Sim D, Read AF. Effect of drug dose and timing of treatment on the emergence of drug resistance in vivo in a malaria model. Evol Med Public Health 2020; 2020:196-210. [PMID: 33209305 PMCID: PMC7652304 DOI: 10.1093/emph/eoaa016] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Revised: 05/15/2020] [Accepted: 05/26/2020] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND AND OBJECTIVES There is a significant interest in identifying clinically effective drug treatment regimens that minimize the de novo evolution of antimicrobial resistance in pathogen populations. However, in vivo studies that vary treatment regimens and directly measure drug resistance evolution are rare. Here, we experimentally investigate the role of drug dose and treatment timing on resistance evolution in an animal model. METHODOLOGY In a series of experiments, we measured the emergence of atovaquone-resistant mutants of Plasmodium chabaudi in laboratory mice, as a function of dose or timing of treatment (day post-infection) with the antimalarial drug atovaquone. RESULTS The likelihood of high-level resistance emergence increased with atovaquone dose. When varying the timing of treatment, treating either very early or late in infection reduced the risk of resistance. When we varied starting inoculum, resistance was more likely at intermediate inoculum sizes, which correlated with the largest population sizes at time of treatment. CONCLUSIONS AND IMPLICATIONS (i) Higher doses do not always minimize resistance emergence and can promote the emergence of high-level resistance. (ii) Altering treatment timing affects the risk of resistance emergence, likely due to the size of the population at the time of treatment, although we did not test the effect of immunity whose influence may have been important in the case of late treatment. (iii) Finding the 'right' dose and 'right' time to maximize clinical gains and limit resistance emergence can vary depending on biological context and was non-trivial even in our simplified experiments. LAY SUMMARY In a mouse model of malaria, higher drug doses led to increases in drug resistance. The timing of drug treatment also impacted resistance emergence, likely due to the size of the population at the time of treatment.
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Affiliation(s)
- Mónica M Acosta
- Department of Biology, Center for Infectious Disease Dynamics, Pennsylvania State University, University Park, PA 16802, USA
| | - Joshua T Bram
- Department of Biology, Center for Infectious Disease Dynamics, Pennsylvania State University, University Park, PA 16802, USA
| | - Derek Sim
- Department of Biology, Center for Infectious Disease Dynamics, Pennsylvania State University, University Park, PA 16802, USA
| | - Andrew F Read
- Department of Biology, Center for Infectious Disease Dynamics, Pennsylvania State University, University Park, PA 16802, USA
- Department of Entomology, Pennsylvania State University, University Park, PA 16802, USA
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Wang R, Yang Q, Zhang S, Hong Y, Zhang M, Jiang S. Trends and correlation of antibiotic susceptibility and antibiotic consumption at a large teaching hospital in China (2007-2016): a surveillance study. Ther Clin Risk Manag 2019; 15:1019-1027. [PMID: 31692506 PMCID: PMC6708394 DOI: 10.2147/tcrm.s210872] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2019] [Accepted: 08/02/2019] [Indexed: 01/22/2023] Open
Abstract
PURPOSE To evaluate the trends and correlation between the antibiotic consumption and susceptibility of eight most frequent isolates in the First Affiliated Hospital of Zhejiang University (2007-2016). METHOD This study was based on the yearly surveillance data in a 2500-bed capacity tertiary-care teaching hospital. Trends and correlation were, respectively, analyzed by linear regression and Pearson's correlation coefficient. RESULTS The consumption of all antibiotics decreased by 10.8% over time, especially first-generation cephalosporins (p=0.001), fourth-generation cephalosporins (p=0.01), aminoglycosides (p<0.001), and fluoroquinolones (p<0.001), but increased remarkably in linezolid, carbapenems, glycopeptides, and third-generation cephalosporins (3GCs). 72.7% of trend analyses indicated increased susceptibility to antibiotics with remarkably decreased consumption. In particular, susceptibility to aminoglycosides and fluoroquinolones remarkably increased in seven of eight pathogens and negatively correlated with the corresponding antibiotic consumption (p<0.05). Isolation density significantly declined in methicillin-resistant Staphylococcus aureus (54.9-41.3%, p=0.009) and in extended-spectrum β-lactamase producing Klebsiella pneumoniae (42.4-15.6%, p=0.007), which positively correlated with the consumption of fluoroquinolones. The susceptibility to antibiotics with increased consumption was almost stable. Decreased trends were only found in K. pneumoniae to imipenem (81-71.3%, p=0.046) and cefoperazone/sulbactam (70.8-61.0%, p=0.014) and in Acinetobacter baumannii to cefoperazone/sulbactam (59-28%, p=0.007), which negatively correlated with the consumption of carbapenems (r=-0.649, p=0.042) and 3GCs/β-lactamase inhibitors (p<0.05), respectively. The consumption of glycopeptides even positively correlated with the growing susceptibility to vancomycin in Enterococcus faecium (r=0.633, p=0.049) and Enterococcus faecalis (r=0.752, p=0.012). CONCLUSION The susceptibility to antibiotics with decreased consumption increased remarkably, but maintained stable to those with growing consumption. The stricter management of carbapenems and 3GCs is necessary.
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Affiliation(s)
- Rongrong Wang
- Department of Pharmacy, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, People’s Republic of China
| | - Qing Yang
- Department of Clinical Laboratory, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, People’s Republic of China
| | - Shaojun Zhang
- Department of Pharmacy, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, People’s Republic of China
| | - Yun Hong
- Department of Pharmacy, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, People’s Republic of China
| | - MeiHua Zhang
- Department of Pharmacy, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, People’s Republic of China
| | - Saiping Jiang
- Department of Pharmacy, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, People’s Republic of China
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Zhang L, Kang Z, Yao L, Gu X, Huang Z, Cai Q, Shen X, Ding H. Pharmacokinetic/Pharmacodynamic Integration to Evaluate the Changes in Susceptibility of Actinobacillus pleuropneumoniae After Repeated Administration of Danofloxacin. Front Microbiol 2018; 9:2445. [PMID: 30369920 PMCID: PMC6194310 DOI: 10.3389/fmicb.2018.02445] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2018] [Accepted: 09/24/2018] [Indexed: 11/14/2022] Open
Abstract
To evaluate the relationship between pharmacokinetic/pharmacodynamic (PK/PD) parameters and changes in susceptibility and resistance frequency of Actinobacillus pleuropneumoniae CVCC 259, a piglet tissue cage (TC) infection model was established. After A. pleuropneumoniae populations maintained at 108 CFU/mL in TCs, piglets were treated with various doses of danofloxacin once daily for 5 consecutive days by intramuscular injection. Both the concentrations of danofloxacin and the population of vial cells were determined. Changes in susceptibility and resistance frequency were monitored. Polymerase chain reaction (PCR) amplification of quinolone resistance-determining regions (QRDRs) and DNA sequencing were performed to identify point mutations in gyrA, gyrB, parC, and parE genes. Furthermore, the susceptibility of mutants to danofloxacin and enrofloxacin was determined in the presence or absence of reserpine to assess whether the mutants were caused by efflux pumps. The MICs and resistant frequency of A. pleuropneumoniae both increased when danofloxacin concentrations fluctuated between MIC99 (0.05 μg/mL) and MPC (mutant prevention concentration, 0.4 μg/mL). As for PK/PD parameters, the resistant mutants were selected and enriched when AUC24h/MIC99 ranged from 34.68 to 148.65 h or AUC24h/MPC ranged from 4.33 to 18.58 h. Substitutions of Ser-83→Tyr or Ser-83→Phe in gyrA and Lys-53→Glu in parC were observed. The susceptibility of mutants obtained via danofloxacin treatment at 1.25 and 2.5 mg/kg were less affected by reserpine. These results demonstrate that maintaining the value of AUC24h/MPC above 18.58 h may produce a desirable antibacterial effect and protect against A. pleuropneumoniae resistance to danofloxacin.
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Affiliation(s)
- Longfei Zhang
- Guangdong Key Laboratory for Veterinary Drug Development and Safety Evaluation, South China Agricultural University, Guangzhou, China
| | - Zheng Kang
- Guangdong Key Laboratory for Veterinary Drug Development and Safety Evaluation, South China Agricultural University, Guangzhou, China
| | - Lihua Yao
- Guangdong Key Laboratory for Veterinary Drug Development and Safety Evaluation, South China Agricultural University, Guangzhou, China
| | - Xiaoyan Gu
- Guangdong Key Laboratory for Veterinary Drug Development and Safety Evaluation, South China Agricultural University, Guangzhou, China
| | - Zilong Huang
- Guangdong Key Laboratory for Veterinary Drug Development and Safety Evaluation, South China Agricultural University, Guangzhou, China
| | - Qinren Cai
- Technical Center for Inspection and Quarantine, Zhuhai Entry-Exit Inspection and Quarantine Bureau, Zhuhai, China
| | - Xiangguang Shen
- Guangdong Key Laboratory for Veterinary Drug Development and Safety Evaluation, South China Agricultural University, Guangzhou, China
| | - Huanzhong Ding
- Guangdong Key Laboratory for Veterinary Drug Development and Safety Evaluation, South China Agricultural University, Guangzhou, China
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Firsov AA, Alieva KN, Strukova EN, Golikova MV, Portnoy YA, Dovzhenko SA, Kobrin MB, Romanov AV, Edelstein MV, Zinner SH. Testing the mutant selection window hypothesis with Staphylococcus aureus exposed to linezolid in an in vitro dynamic model. J Antimicrob Chemother 2017; 72:3100-3107. [DOI: 10.1093/jac/dkx249] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2017] [Accepted: 06/22/2017] [Indexed: 11/13/2022] Open
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In Vitro Resistance Selection in Shigella flexneri by Azithromycin, Ceftriaxone, Ciprofloxacin, Levofloxacin, and Moxifloxacin. Antimicrob Agents Chemother 2017; 61:AAC.00086-17. [PMID: 28483960 DOI: 10.1128/aac.00086-17] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2017] [Accepted: 05/04/2017] [Indexed: 01/02/2023] Open
Abstract
Shigella flexneri continues to be a major cause of diarrhea-associated illness, and increasing resistance to first-line antimicrobials complicates the treatment of infections caused by this pathogen. We investigated the pharmacodynamics of current antimicrobial treatments for shigellosis to determine the likelihood of resistance promotion with continued global antimicrobial use. The mutant prevention concentration (MPC) and mutant selection window (MSW) were determined for azithromycin, ceftriaxone, ciprofloxacin, levofloxacin, and moxifloxacin against a wild-type strain of S. flexneri (ATCC 12022) and an isogenic gyrA mutant (m-12022). Time-kill assays were performed to determine antimicrobial killing. Concentrations of approved doses of ciprofloxacin, levofloxacin, and moxifloxacin are predicted to surpass the MPC for a majority of the dosage interval against ATCC 12022. However, against m-12022, concentrations of all fluoroquinolones are predicted to fall below the MPC and remain in the MSW for a majority of the dosage interval. Concentrations of ceftriaxone fall within the MSW for the majority of the dosage interval for both strains. All agents other than azithromycin displayed bactericidal activity in time-kill assays. Results of pharmacodynamic analyses suggest that all tested fluoroquinolones would achieve a favorable area under the concentration-time curve (AUC)/MPC ratio for ATCC 12022 and would restrict selective enrichment of mutants but that mutant selection in m-12022 would be likely if ciprofloxacin were used. Based on pharmacodynamic analyses, azithromycin and ceftriaxone are predicted to promote mutant selection in both strains. Confirmation of these findings and examination of novel treatment regimens using in vivo studies are warranted.
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Nan J, Hao H, Xie S, Pan Y, Xi C, Mao F, Liu Z, Huang L, Yuan Z. Pharmacokinetic and pharmacodynamic integration and modeling of acetylkitasamycin in swine for Clostridium perfringens. J Vet Pharmacol Ther 2017; 40:641-655. [PMID: 28464333 DOI: 10.1111/jvp.12404] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2016] [Accepted: 02/22/2017] [Indexed: 12/01/2022]
Abstract
The aim of this study was to establish an integrated pharmacokinetic/pharmacodynamic (PK/PD) modeling approach of acetylkitasamycin for designing dosage regimens and decreasing the emergence of drug-resistant bacteria. After oral administration of acetylkitasamycin to healthy and infected pigs at the dose of 50 mg/kg body weights (bw), a rapid and sensitive LC-MS/MS method was developed and validated for determining the concentration change of the major components of acetylkitasamycin and its possible metabolite kitasamycin in the intestinal samples taken from the T-shape ileal cannula. The PK parameters, including the integrated peak concentration (Cmax ), the time when the maximum concentration reached (Tmax ) and the area under the concentration-time curve (AUC), were calculated by WinNonlin software. The minimum inhibitory concentration (MIC) of 60 C. perfringens strains was determined following CLSI guideline. The in vitro and ex vivo activities of acetylkitasamycin in intestinal tract against a pathogenic strain of C. perfringens type A (CPFK122995) were established by the killing curve. Our PK data showed that the integrated Cmax , Tmax , and AUC were 14.57-15.81 μg/ml, 0.78-2.52 hR, and 123.84-152.32 μg hr/ml, respectively. The PD data show that MIC50 and MIC90 of the 60 C. perfringens isolates were 3.85 and 26.45 μg/ml, respectively. The ex vivo growth inhibition data were fitted to the inhibitory sigmoid Emax equation to provide the values of AUC/MIC to produce bacteriostasis (4.84 hr), bactericidal activity (15.46 hr), and bacterial eradication (24.99 hr). A dosage regimen of 18.63 mg/kg bw every 12 hr could be sufficient in the prevention of C. perfringens infection. The therapeutic dosage regimen for C. perfringens infection was at the dose of 51.36 mg/kg bw every 12 hr for 3 days. In summary, the dosage regimen for the treatment of C. perfringens in pigs administered with acetylkitasamycin was designed using PK/PD integrate model. The designed dose regimen could to some extent decrease the risk for emergence of macrolide resistance.
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Affiliation(s)
- J Nan
- National Reference Laboratory of Veterinary Drug Residues (HZAU) and MAO Key Laboratory for Detection of Veterinary Drug Residues, Huazhong Agricultural University, Wuhan, Hubei, China.,MOA Laboratory for Risk Assessment of Quality and Safety of Livestock and Poultry Products, Huazhong Agricultural University, Wuhan, Hubei, China
| | - H Hao
- National Reference Laboratory of Veterinary Drug Residues (HZAU) and MAO Key Laboratory for Detection of Veterinary Drug Residues, Huazhong Agricultural University, Wuhan, Hubei, China.,MOA Laboratory for Risk Assessment of Quality and Safety of Livestock and Poultry Products, Huazhong Agricultural University, Wuhan, Hubei, China
| | - S Xie
- MOA Laboratory for Risk Assessment of Quality and Safety of Livestock and Poultry Products, Huazhong Agricultural University, Wuhan, Hubei, China.,Hubei Collaborative Innovation Center for Animal Nutrition and Feed Safety, Huazhong Agricultural University, Wuhan, Hubei, China
| | - Y Pan
- MOA Laboratory for Risk Assessment of Quality and Safety of Livestock and Poultry Products, Huazhong Agricultural University, Wuhan, Hubei, China.,Hubei Collaborative Innovation Center for Animal Nutrition and Feed Safety, Huazhong Agricultural University, Wuhan, Hubei, China
| | - C Xi
- MOA Laboratory for Risk Assessment of Quality and Safety of Livestock and Poultry Products, Huazhong Agricultural University, Wuhan, Hubei, China.,Hubei Collaborative Innovation Center for Animal Nutrition and Feed Safety, Huazhong Agricultural University, Wuhan, Hubei, China
| | - F Mao
- MOA Laboratory for Risk Assessment of Quality and Safety of Livestock and Poultry Products, Huazhong Agricultural University, Wuhan, Hubei, China.,Hubei Collaborative Innovation Center for Animal Nutrition and Feed Safety, Huazhong Agricultural University, Wuhan, Hubei, China
| | - Z Liu
- MOA Laboratory for Risk Assessment of Quality and Safety of Livestock and Poultry Products, Huazhong Agricultural University, Wuhan, Hubei, China.,Hubei Collaborative Innovation Center for Animal Nutrition and Feed Safety, Huazhong Agricultural University, Wuhan, Hubei, China
| | - L Huang
- MOA Laboratory for Risk Assessment of Quality and Safety of Livestock and Poultry Products, Huazhong Agricultural University, Wuhan, Hubei, China.,Hubei Collaborative Innovation Center for Animal Nutrition and Feed Safety, Huazhong Agricultural University, Wuhan, Hubei, China
| | - Z Yuan
- National Reference Laboratory of Veterinary Drug Residues (HZAU) and MAO Key Laboratory for Detection of Veterinary Drug Residues, Huazhong Agricultural University, Wuhan, Hubei, China.,MOA Laboratory for Risk Assessment of Quality and Safety of Livestock and Poultry Products, Huazhong Agricultural University, Wuhan, Hubei, China.,Hubei Collaborative Innovation Center for Animal Nutrition and Feed Safety, Huazhong Agricultural University, Wuhan, Hubei, China
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Validation of the mutant selection window hypothesis with fosfomycin against Escherichia coli and Pseudomonas aeruginosa: an in vitro and in vivo comparative study. J Antibiot (Tokyo) 2016; 70:166-173. [PMID: 27756910 DOI: 10.1038/ja.2016.124] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2016] [Revised: 08/28/2016] [Accepted: 09/12/2016] [Indexed: 11/09/2022]
Abstract
The purpose of this study was to validate the mutant selection window (MSW) hypothesis in vitro and in vivo with Escherichia coli and Pseudomonas aeruginosa exposed to fosfomycin. Two standard strains of Gram-negative bacteria, those are E. coli ATCC 25922 and P. aeruginosa ATCC 27853, were exposed to fosfomycin at concentrations below MIC, between the MIC and the mutant prevention concentration (MPC), and above the MPC in Luria-Bertani broth and in a tissue-cage infection model, respectively. With the in vitro time-kill studies, there were bacterial re-growth and emergence of resistance thereafter for both strains at antibiotic concentrations of × 4, × 8 and × 16 MIC. In our animal model, the loss in susceptibility of P. aeruginosa at fosfomycin concentrations fluctuated between the lower and upper boundaries of the MSW. In contrast, the emergence of resistant mutants of E. coli was not observed in vivo, regardless of fosfomycin dosage. Interestingly, the in vitro-isolated resistant mutants of E. coli showed a decreased growth rate compared with the susceptible parental strains, whereas no fitness cost in P. aeruginosa was observed. The emergence of antibiotic resistance is shaped by several factors. MSW theory may not apply to all antimicrobial-pathogen combinations. Before it can be used as a framework for the design of antimicrobial therapy, the existence of the window must be demonstrated not only in vitro but also in vivo.
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Xiong M, Wu X, Ye X, Zhang L, Zeng S, Huang Z, Wu Y, Sun J, Ding H. Relationship between Cefquinome PK/PD Parameters and Emergence of Resistance of Staphylococcus aureus in Rabbit Tissue-Cage Infection Model. Front Microbiol 2016; 7:874. [PMID: 27375594 PMCID: PMC4896111 DOI: 10.3389/fmicb.2016.00874] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2016] [Accepted: 05/24/2016] [Indexed: 11/13/2022] Open
Abstract
In order to explore the relationship between different antibiotic dosing regimens and selective enrichment of resistant strains, tissue-cage infection model was established in rabbits to study relationship between cefquinome pharmacokinetic/pharmacodynamic parameters and the change of susceptibility of Staphylococcus aureus (S. aureus). In this model, above 108 CFU/mL of S. aureus culture were exposed to cefquinome concentrations below the MIC99 (the minimal concentration that inhibits colony formation by 99% in vitro, 0.3 μg/mL), between the MIC99 and the MPC (the mutant prevent concentration in vitro, 1.6 μg/mL), and above the MPC after intramuscular injection with cefquinome at doses of 4, 8, 16, and 32 mg/kg of body weight (bw) once daily for 5 days or 4, 8, 16, and 24 mg/kg of bw twice daily for 2.5 days. Samples of tissue-cage fluid were collected from the tissue-cage at 2, 4, 6, 8, 10, 12, 24 h after each dosing (one dosing daily) or at 2, 4, 6, 8, 10, and 12 h (two dosing daily). Cefquinome concentration, susceptibility of S. aureus to cefquinome, and bacterial numbers at the infected site were monitored. The MICs of S. aureus and the fraction of resistant bacteria both increased when cefquinome concentrations fluctuated between the MIC99 and MPC. Resistant bacteria were selected in vivo when %T > MPC was < 58% of administration interval or %T > MIC99 was ≥70% of administration interval. These findings demonstrate that low-level, cefquinome-resistant S. aureus were selected predominantly when drug concentrations fell inside a concentration window in in vivo model, which was evidenced by pulsed-field gel electrophoresis. The selection of resistant bacteria arose from both susceptible bacteria being killed and resistant bacteria re-growth. Keeping drug concentrations above the MPC for ≥58% of administration interval provides a strategy to achieve effective antibacterial activity and minimize the emergence of resistance to cefquinome.
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Affiliation(s)
- Mingpeng Xiong
- National Risk Assessment Laboratory for Antimicrobial Resistance of Microorganisms of Animal Original Bacteria, College of Veterinary Medicine, South China Agricultural University Guangzhou, China
| | - Xun Wu
- National Risk Assessment Laboratory for Antimicrobial Resistance of Microorganisms of Animal Original Bacteria, College of Veterinary Medicine, South China Agricultural University Guangzhou, China
| | - Xiaomei Ye
- National Risk Assessment Laboratory for Antimicrobial Resistance of Microorganisms of Animal Original Bacteria, College of Veterinary Medicine, South China Agricultural University Guangzhou, China
| | - Longfei Zhang
- National Risk Assessment Laboratory for Antimicrobial Resistance of Microorganisms of Animal Original Bacteria, College of Veterinary Medicine, South China Agricultural University Guangzhou, China
| | - Shuyi Zeng
- National Risk Assessment Laboratory for Antimicrobial Resistance of Microorganisms of Animal Original Bacteria, College of Veterinary Medicine, South China Agricultural University Guangzhou, China
| | - Zilong Huang
- National Risk Assessment Laboratory for Antimicrobial Resistance of Microorganisms of Animal Original Bacteria, College of Veterinary Medicine, South China Agricultural University Guangzhou, China
| | - Yuzhi Wu
- National Risk Assessment Laboratory for Antimicrobial Resistance of Microorganisms of Animal Original Bacteria, College of Veterinary Medicine, South China Agricultural University Guangzhou, China
| | - Jian Sun
- National Risk Assessment Laboratory for Antimicrobial Resistance of Microorganisms of Animal Original Bacteria, College of Veterinary Medicine, South China Agricultural University Guangzhou, China
| | - Huanzhong Ding
- National Risk Assessment Laboratory for Antimicrobial Resistance of Microorganisms of Animal Original Bacteria, College of Veterinary Medicine, South China Agricultural University Guangzhou, China
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Li Y, Feng B, Gu X, Yang D, Zeng Z, Zhang B, Ding H. Correlation of PK/PD Indices with Resistance Selection for Cefquinome against Staphylococcus aureus in an In Vitro Model. Front Microbiol 2016. [PMCID: PMC4828644 DOI: 10.3389/fmicb.2016.00466] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- Yafei Li
- Laboratory of Veterinary Pharmacology, College of Veterinary Medicine, South China Agricultural UniversityGuangzhou, China
| | - Baoyi Feng
- Laboratory of Veterinary Pharmacology, College of Veterinary Medicine, South China Agricultural UniversityGuangzhou, China
| | - Xiaoyan Gu
- Centre for Veterinary Drug Residues, College of Veterinary Medicine, South China Agricultural UniversityGuangzhou, China
| | - Dawei Yang
- China Institute of Veterinary Drug ControlBeijing, China
| | - Zhenling Zeng
- Laboratory of Veterinary Pharmacology, College of Veterinary Medicine, South China Agricultural UniversityGuangzhou, China
| | - Bingxu Zhang
- Laboratory of Veterinary Pharmacology, College of Veterinary Medicine, South China Agricultural UniversityGuangzhou, China
| | - Huanzhong Ding
- Laboratory of Veterinary Pharmacology, College of Veterinary Medicine, South China Agricultural UniversityGuangzhou, China
- *Correspondence: Huanzhong Ding,
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Application of PK/PD Modeling in Veterinary Field: Dose Optimization and Drug Resistance Prediction. BIOMED RESEARCH INTERNATIONAL 2016; 2016:5465678. [PMID: 26989688 PMCID: PMC4771886 DOI: 10.1155/2016/5465678] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/05/2015] [Revised: 12/21/2015] [Accepted: 01/11/2016] [Indexed: 12/14/2022]
Abstract
Among veterinary drugs, antibiotics are frequently used. The true mean of antibiotic treatment is to administer dose of drug that will have enough high possibility of attaining the preferred curative effect, with adequately low chance of concentration associated toxicity. Rising of antibacterial resistance and lack of novel antibiotic is a global crisis; therefore there is an urgent need to overcome this problem. Inappropriate antibiotic selection, group treatment, and suboptimal dosing are mostly responsible for the mentioned problem. One approach to minimizing the antibacterial resistance is to optimize the dosage regimen. PK/PD model is important realm to be used for that purpose from several years. PK/PD model describes the relationship between drug potency, microorganism exposed to drug, and the effect observed. Proper use of the most modern PK/PD modeling approaches in veterinary medicine can optimize the dosage for patient, which in turn reduce toxicity and reduce the emergence of resistance. The aim of this review is to look at the existing state and application of PK/PD in veterinary medicine based on in vitro, in vivo, healthy, and disease model.
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Linder KE, Nicolau DP, Nailor MD. Predicting and preventing antimicrobial resistance utilizing pharmacodynamics: Part I gram positive bacteria. Expert Opin Drug Metab Toxicol 2016; 12:267-80. [PMID: 26751348 DOI: 10.1517/17425255.2016.1141197] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
INTRODUCTION Antimicrobial resistance is a potentially inevitable consequence of widespread use of antibiotics in the healthcare system. An enhanced understanding of pharmacodynamic (PD) targets that prevent antimicrobial resistance development will improve currently availably therapies and help to guide future drug development strategies. Current in vitro methods to predict bacterial resistance to antimicrobials consist of serial dilution experiments, determination of the mutant prevention concentration (MPC), mutant selection window (MSW), and human simulated pharmacodynamics studies. Clinical trial data and real -world surveillance studies can help validate or disprove in vitro modeling. AREAS COVERED This review will discuss methods of predicting development of resistance and how the use of pharmacodynamics can reduce or eliminate the emergence of resistance among Staphylococcus aureus, Streptococcus pneumoniae, and Enterococcus species. EXPERT OPINION Pharmacodynamic targets can be used successfully to guide antimicrobial therapy to prevent resistance development. Currently, PD targets do not take into consideration horizontal resistance gene transfer and various factors may lead to different PD targets based on sites of infection. Further research is necessary to guide future drug development strategies and optimize new drug therapies.
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Affiliation(s)
- Kristin E Linder
- a Department of Pharmacy , Hartford Hospital , Hartford , CT , USA
| | - David P Nicolau
- b Center for Anti-infective Research and Development , Hartford Hospital , Hartford , CT , USA
| | - Michael D Nailor
- a Department of Pharmacy , Hartford Hospital , Hartford , CT , USA.,c Department of Pharmacy Practice , University of Connecticut School of Pharmacy , Storrs , CT , USA
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Day T, Read AF. Does High-Dose Antimicrobial Chemotherapy Prevent the Evolution of Resistance? PLoS Comput Biol 2016; 12:e1004689. [PMID: 26820986 PMCID: PMC4731197 DOI: 10.1371/journal.pcbi.1004689] [Citation(s) in RCA: 101] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2015] [Accepted: 11/30/2015] [Indexed: 12/25/2022] Open
Abstract
High-dose chemotherapy has long been advocated as a means of controlling drug resistance in infectious diseases but recent empirical studies have begun to challenge this view. We develop a very general framework for modeling and understanding resistance emergence based on principles from evolutionary biology. We use this framework to show how high-dose chemotherapy engenders opposing evolutionary processes involving the mutational input of resistant strains and their release from ecological competition. Whether such therapy provides the best approach for controlling resistance therefore depends on the relative strengths of these processes. These opposing processes typically lead to a unimodal relationship between drug pressure and resistance emergence. As a result, the optimal drug dose lies at either end of the therapeutic window of clinically acceptable concentrations. We illustrate our findings with a simple model that shows how a seemingly minor change in parameter values can alter the outcome from one where high-dose chemotherapy is optimal to one where using the smallest clinically effective dose is best. A review of the available empirical evidence provides broad support for these general conclusions. Our analysis opens up treatment options not currently considered as resistance management strategies, and it also simplifies the experiments required to determine the drug doses which best retard resistance emergence in patients. The evolution of antimicrobial resistant pathogens threatens much of modern medicine. For over one hundred years, the advice has been to ‘hit hard’, in the belief that high doses of antimicrobials best contain resistance evolution. We argue that nothing in evolutionary theory supports this as a good rule of thumb in the situations that challenge medicine. We show instead that the only generality is to either use the highest tolerable drug dose or the lowest clinically effective dose; that is, one of the two edges of the therapeutic window. This approach suggests treatment options not currently considered, and simplifies the experiments required to identify the dose that best retards resistance evolution.
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Affiliation(s)
- Troy Day
- Department of Mathematics and Statistics, Jeffery Hall, Queen’s University, Kingston, Ontario, Canada
- Department of Biology, Queen’s University, Kingston, Ontario, Canada
- The Fogarty International Center, National Institutes of Health, Bethesda, Maryland, United States of America
- * E-mail:
| | - Andrew F. Read
- The Fogarty International Center, National Institutes of Health, Bethesda, Maryland, United States of America
- Center for Infectious Disease Dynamics, Departments of Biology and Entomology, The Pennsylvania State University, University Park, Pennsylvania, United States of America
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Mei Q, Ye Y, Zhu YL, Cheng J, Yang HF, Liu YY, Li HR, Li JB. Use of Monte Carlo simulation to evaluate the development of vancomycin resistance in meticillin-resistant Staphylococcus aureus. Int J Antimicrob Agents 2015; 45:652-6. [PMID: 25813394 DOI: 10.1016/j.ijantimicag.2015.01.018] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2014] [Revised: 01/20/2015] [Accepted: 01/23/2015] [Indexed: 11/25/2022]
Abstract
Monte Carlo simulations were performed for various vancomycin dosage regimens to evaluate the potential for development of vancomycin resistance in meticillin-resistant Staphylococcus aureus (MRSA). When the target of free AUC(24)/MIC≥200 was considered (where AUC(24) is the area under the drug concentration-time curve in a 24-h interval and MIC is the minimum inhibitory concentration), a standard dose regimen (1000 mg every 12 h) yielded unacceptable simulated outcomes in patients with normal renal function; in particular, the probability of target attainment (PTA) was only 30.5% at an MIC of 1mg/L. For the same dosage regimens and the mutant prevention concentration (MPC)-based pharmacokinetic target (total AUC(24)/MPC>15), the cumulative fraction of response exceeded 80% for all renal function strata; low values of PTA (<80%) were obtained only for isolates with MPCs of ≥22.4 mg/L, which consisted of all 21 strains of heterogeneous vancomycin-intermediate S. aureus (hVISA) and a handful of non-hVISA strains with MICs of 2mg/L (32%; 16/50). Based on the current status of vancomycin resistance, we conclude that total AUC(24)/MPC>15, derived from in vivo experiments, is more suitable to predict the development of vancomycin resistance. In clinical practice, individualised vancomycin therapy should be considered to minimise selection of resistance mutations.
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Affiliation(s)
- Qing Mei
- Department of Infectious Diseases, First Affiliated Hospital of Anhui Medical University, Hefei, Anhui 230022, China
| | - Ying Ye
- Department of Infectious Diseases, First Affiliated Hospital of Anhui Medical University, Hefei, Anhui 230022, China; Anhui Center for Surveillance of Bacterial Resistance, Hefei, Anhui 230022, China; Institute of Bacterium Resistance, Anhui Medical University, Hefei, Anhui 230022, China
| | - Yu-lin Zhu
- Department of Pediatrics, First Affiliated Hospital of Anhui Medical University, Hefei, Anhui 230022, China
| | - Jun Cheng
- Department of Infectious Diseases, First Affiliated Hospital of Anhui Medical University, Hefei, Anhui 230022, China
| | - Hai-fei Yang
- Department of Infectious Diseases, First Affiliated Hospital of Anhui Medical University, Hefei, Anhui 230022, China
| | - Yan-yan Liu
- Anhui Center for Surveillance of Bacterial Resistance, Hefei, Anhui 230022, China; Institute of Bacterium Resistance, Anhui Medical University, Hefei, Anhui 230022, China
| | - Hong-ru Li
- Class 7 Grade 2012, The Eight-year Program on Clinical Medicine, Xiangya School of Medicine, Central South University, Changsha, Hunan 410008, China
| | - Jia-bin Li
- Department of Infectious Diseases, First Affiliated Hospital of Anhui Medical University, Hefei, Anhui 230022, China; Anhui Center for Surveillance of Bacterial Resistance, Hefei, Anhui 230022, China; Institute of Bacterium Resistance, Anhui Medical University, Hefei, Anhui 230022, China; Department of Infectious Diseases, Chaohu Hospital Affiliated to Anhui Medical University, Chaohu, Anhui 238000, China.
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Day T, Huijben S, Read AF. Is selection relevant in the evolutionary emergence of drug resistance? Trends Microbiol 2015; 23:126-33. [PMID: 25680587 DOI: 10.1016/j.tim.2015.01.005] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2014] [Revised: 01/12/2015] [Accepted: 01/13/2015] [Indexed: 10/24/2022]
Abstract
The emergence of drug-resistant pathogens is often considered a canonical case of evolution by natural selection. Here we argue that the strength of selection can be a poor predictor of the rate of resistance emergence. It is possible for a resistant strain to be under negative selection and still emerge in an infection or spread in a population. Measuring the right parameters is a necessary first step toward the development of evidence-based resistance-management strategies. We argue that it is the absolute fitness of the resistant strains that matters most and that a primary determinant of the absolute fitness of a resistant strain is the ecological context in which it finds itself.
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Affiliation(s)
- Troy Day
- Department of Mathematics and Statistics, Jeffery Hall, Queen's University, Kingston, ON K7L 3N6, Canada; Department of Biology, Queen's University, Kingston, ON K7L 3N6, Canada; The Fogarty International Center, National Institutes of Health, Bethesda, MD 20892, USA.
| | - Silvie Huijben
- ISGlobal, Barcelona Centre for International Health Research (CRESIB), Hospital Clínic, Universitat de Barcelona, Barcelona, Spain
| | - Andrew F Read
- The Fogarty International Center, National Institutes of Health, Bethesda, MD 20892, USA; Center for Infectious Disease Dynamics, Departments of Biology and Entomology, Pennsylvania State University, University Park, PA 16802, USA
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Zhang B, Gu X, Li Y, Li X, Gu M, Zhang N, Shen X, Ding H. In vivo evaluation of mutant selection window of cefquinome against Escherichia coli in piglet tissue-cage model. BMC Vet Res 2014; 10:297. [PMID: 25511985 PMCID: PMC4279896 DOI: 10.1186/s12917-014-0297-1] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2014] [Accepted: 12/08/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The resistance of cephalosporins is significantly serious in veterinary clinic. In order to inhibit the bacterial resistance production, the mutant selection window (MSW) hypothesis with Escherichia coli (E. coli) ATCC 25922 exposed to cefquinome in an animal tissue-cage model was investigated. RESULTS Localized infection with E. coli was established in piglets, and the infected animals were administrated intramuscularly with various doses and intervals of cefquinome to provide antibiotic concentrations below the MIC99, between the MIC99 and the mutant prevention concentration (MPC), and above the MPC. E. coli lost susceptibility when drug concentrations fluctuated between the lower and upper boundaries of the window, which defined in vitro as the MIC99 (0.06 μg/mL) and the MPC (0.16 μg/mL) respectively. For PK/PD parameters, there were no mutant selection enrichment when T>MIC99 was ≤ 25% or T>MPC was ≥ 50% of administration interval. When T>MIC99 was > 25% and T>MPC was <50% of administration interval, resistance selection was observed. When AUC24 h/MIC99 and AUC24 h/MPC were considered, the mutant selection window extended from 32.84 h to 125.64 h and from 12.83 h to 49.09 h, respectively. CONCLUSIONS These findings demonstrate that the MSW exists in vivo for time-dependent antimicrobial agents, and its boundaries fit well with those determined in vitro. Maintenance of antimicrobial concentrations above the MPC for > 50% of administration interval is a straightforward way to restrict the acquisition of resistance in this tissue cage model. This situation was achieved with daily intramuscular doses of 1 mg cefquinome/kg body weight.
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Affiliation(s)
- Bingxu Zhang
- National Reference Laboratory of Veterinary Drug Residues (SCAU), College of Veterinary Medicine, South China Agricultural University, Guangzhou, 510642, China.
| | - Xiaoyan Gu
- National Reference Laboratory of Veterinary Drug Residues (SCAU), College of Veterinary Medicine, South China Agricultural University, Guangzhou, 510642, China.
| | - Yafei Li
- National Reference Laboratory of Veterinary Drug Residues (SCAU), College of Veterinary Medicine, South China Agricultural University, Guangzhou, 510642, China.
| | - Xiaohong Li
- National Reference Laboratory of Veterinary Drug Residues (SCAU), College of Veterinary Medicine, South China Agricultural University, Guangzhou, 510642, China.
| | - Mengxiao Gu
- National Reference Laboratory of Veterinary Drug Residues (SCAU), College of Veterinary Medicine, South China Agricultural University, Guangzhou, 510642, China.
| | - Nan Zhang
- National Reference Laboratory of Veterinary Drug Residues (SCAU), College of Veterinary Medicine, South China Agricultural University, Guangzhou, 510642, China.
| | - Xiangguang Shen
- National Reference Laboratory of Veterinary Drug Residues (SCAU), College of Veterinary Medicine, South China Agricultural University, Guangzhou, 510642, China.
| | - Huanzhong Ding
- National Reference Laboratory of Veterinary Drug Residues (SCAU), College of Veterinary Medicine, South China Agricultural University, Guangzhou, 510642, China.
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26
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Mei Q, Ye Y, Zhu YL, Cheng J, Chang X, Liu YY, Li HR, Li JB. Testing the mutant selection window hypothesis in vitro and in vivo with Staphylococcus aureus exposed to fosfomycin. Eur J Clin Microbiol Infect Dis 2014; 34:737-44. [PMID: 25424036 DOI: 10.1007/s10096-014-2285-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2014] [Accepted: 11/13/2014] [Indexed: 01/29/2023]
Abstract
The purpose of this study was to test the mutant selection window (MSW) hypothesis in vitro and in vivo with Staphylococcus aureus exposed to fosfomycin. With the in vitro time-kill studies, S. aureus ATCC 29213 [with a minimal concentration that inhibits colony formation by 99% (MIC99) of 2.2 μg/mL and a mutant prevention concentration (MPC) of 57.6 μg/mL] lost fosfomycin susceptibility at antibiotic concentrations (2×, 4×, and 8× MIC) that are between the lower and upper boundaries of the MSW. In the tissue-cage model, S. aureus was exposed to fosfomycin pharmacokinetics at concentrations below the MIC99, between the MIC99 and the MPC, and above the MPC, respectively. Changes in susceptibility and counts of total and resistant viable bacteria were monitored in tissue-cage fluid obtained daily. However, the selection of resistant mutants was not observed during antibacterial treatment and 48 h after the termination of fosfomycin treatment, regardless of the fosfomycin dosage. Besides, we found no differences between the in vitro-isolated mutant and its sensitive parental strain, which indicates the absence of fitness cost of fosfomycin resistance in S. aureus ATCC 29213. These findings demonstrate that agar plate determinations do not fit the MSW for fosfomycin treatment of rabbits infected with S. aureus ATCC 29213; therefore, the existence of the window must be demonstrated not only in vitro but also in vivo. Further research is needed on the exact mechanism of resistance.
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Affiliation(s)
- Q Mei
- Department of Infectious Diseases, First Affiliated Hospital of Anhui Medical University, Hefei, 230022, Anhui, China
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Testing the mutant selection window hypothesis with Escherichia coli exposed to levofloxacin in a rabbit tissue cage infection model. Eur J Clin Microbiol Infect Dis 2013; 33:385-9. [DOI: 10.1007/s10096-013-1968-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2013] [Accepted: 08/23/2013] [Indexed: 10/26/2022]
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Soothill G, Hu Y, Coates A. Can we prevent antimicrobial resistance by using antimicrobials better? Pathogens 2013; 2:422-35. [PMID: 25437042 PMCID: PMC4235724 DOI: 10.3390/pathogens2020422] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2013] [Revised: 05/24/2013] [Accepted: 06/01/2013] [Indexed: 12/05/2022] Open
Abstract
Since their development over 60 years ago, antimicrobials have become an integral part of healthcare practice worldwide. Recently, this has been put in jeopardy by the emergence of widespread antimicrobial resistance, which is one of the major problems facing modern medicine. In the past, the development of new antimicrobials kept us one step ahead of the problem of resistance, but only three new classes of antimicrobials have reached the market in the last thirty years. A time is therefore approaching when we may not have effective treatment against bacterial infections, particularly for those that are caused by Gram-negative organisms. An important strategy to reduce the development of antimicrobial resistance is to use antimicrobials more appropriately, in ways that will prevent resistance. This involves a consideration of the pharmacokinetic and pharmacodynamics properties of antimicrobials, the possible use of combinations, and more appropriate choice of antimicrobials, which may include rapid diagnostic testing and antimicrobial cycling. Examples given in this review include Mycobacterium tuberculosis, Gram-negative and Gram-positive organisms. We shall summarise the current evidence for these strategies and outline areas for future development.
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Affiliation(s)
- Germander Soothill
- Barts and The London School of Medicine and Dentistry, Queen Mary, University of London, Garrod Building, Turner Street, Whitechapel, London, E1 2AD, UK.
| | - Yanmin Hu
- Medical Microbiology, Centre for Infection, Division of Clinical Studies, St George's, University of London, Cranmer Terrace, London SW17 0RE, UK.
| | - Anthony Coates
- Medical Microbiology, Centre for Infection, Division of Clinical Studies, St George's, University of London, Cranmer Terrace, London SW17 0RE, UK.
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