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Home / Equine Research Bank / J Vet Intern Med / An evaluation of serum gentamicin concentrations and bacteri...
Journal of veterinary internal medicine2018; 32(3); 1194-1201; doi: 10.1111/jvim.15078

An evaluation of serum gentamicin concentrations and bacterial susceptibility to gentamicin in equine practice.

Abstract: Therapeutic drug monitoring and minimum inhibitory concentration (MIC) data allow more informed use of gentamicin. Objective: To measure peak and trough serum gentamicin concentrations in horses after a 6.6 mg/kg dose of gentamicin given IV and the MIC of gentamicin of bacteria for which gentamicin might be selected. Methods: Retrospective analysis of hospital records. Peak and trough plasma gentamicin concentrations were measured after 6.6 mg/kg gentamicin IV in 339 hospitalized horses. The MIC of gentamicin was measured for 503 isolates from ambulatory practice and 33 from hospital practice. The distribution of gentamicin concentrations and MIC results were compared to current recommendations for MIC breakpoints. Results: The median serum gentamicin concentration at 60 minutes after administration (C ) was 21.4 μg/mL with a distribution indicating that bacteria with MIC ≥2 μg/mL were unlikely to be exposed to sufficient gentamicin for effective killing. Approximately 90% of isolates from ambulatory practice and 36% of hospital isolates had MICs at or below breakpoints for susceptibility with most of the remainder unlikely to be responsive, even to higher IV doses. Conclusions: Gentamicin at a dosage of 6.6 mg/kg IV is likely to be effective against the majority of infections encountered in ambulatory practice, but less effective in an equine hospital. Because there was a dichotomy of most bacteria as being clearly susceptible or clearly resistant to gentamicin, it appears unlikely that higher doses would have been more efficacious, especially in the hospitalized population in our study.
Copyright © 2018 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of the American College of Veterinary Internal Medicine.
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Publication Date: 2018-03-25 PubMed ID: 29575239PubMed Central: PMC5980452DOI: 10.1111/jvim.15078Google Scholar: Lookup
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  • Journal Article

Summary

This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.

The research article investigates the effectiveness of the antibiotic gentamicin in treating infections in horses, by analyzing serum concentrations in the horse’s body and bacterial susceptibility to the drug.

Objective & Methodology

  • The goal of this research was to measure both the peak and trough concentrations of gentamicin in the bloodstream of horses after being given a Intravenous (IV) dose of 6.6 mg/kg. Additionally, the minimum inhibitory concentration (MIC) of gentamin – the lowest concentration that prevents bacterial growth – was measured for various bacterial strains.
  • To perform these measurements, a retrospective analysis of hospital records were explored.
  • 339 hospitalised horses were part of the study for the analysis of peak and trough gentamicin concentration.
  • The MIC was measured for 536 bacterial strains in total, from which 503 originated from ambulatory practices, and 33 from a hospital environment.
  • The distribution of gentamicin concentrations and the MIC results were weighed against current recommendations for MIC thresholds.

Findings

  • The study found that the median concentration of gentamicin in the horses’ bloodstream was 21.4 μg/mL, 60 minutes after administration.
  • From this data distribution, it was inferred that bacteria with a MIC of 2 μg/mL or higher were less likely to be exposed to sufficient quantities of gentamicin for effective bacterial elimination.
  • About 90% of the bacterial strains from ambulatory practices and 36% from the hospital had MICs at or below the defined breakpoints, indicating successful drug susceptibility. The remaining strains were predicted to be unresponsive, even to larger doses.

Conclusion

  • Based on the study findings, it was concluded that a 6.6 mg/kg IV dose of gentamicin is likely to be effective against most infections found in ambulatory practices, but the treatment appears less effective in a hospital environment for horses.
  • Moreover, due to the clear division showcasing bacteria either being susceptible or resistant to gentamicin, it was suggested that increasing the medication dosage would not increase the efficacy, especially in the considered hospitalised population.

Cite This Article

APA
Durham AE. (2018). An evaluation of serum gentamicin concentrations and bacterial susceptibility to gentamicin in equine practice. J Vet Intern Med, 32(3), 1194-1201. https://doi.org/10.1111/jvim.15078

Publication

Journal of veterinary internal medicine
ISSN: 1939-1676
NlmUniqueID: 8708660
Country: United States
Language: English
Volume: 32
Issue: 3
Pages: 1194-1201

Researcher Affiliations

Durham, Andy E
  • Liphook Equine Hospital, Liphook, Hampshire, United Kingdom.

MeSH Terms

  • Animals
  • Anti-Bacterial Agents / administration & dosage
  • Anti-Bacterial Agents / blood
  • Anti-Bacterial Agents / therapeutic use
  • Bacterial Infections / drug therapy
  • Bacterial Infections / microbiology
  • Bacterial Infections / veterinary
  • Gentamicins / administration & dosage
  • Gentamicins / blood
  • Gentamicins / therapeutic use
  • Horse Diseases / blood
  • Horse Diseases / drug therapy
  • Horse Diseases / microbiology
  • Horses
  • Microbial Sensitivity Tests / veterinary
  • Retrospective Studies

References

This article includes 28 references
  1. MacGowan AP, Wise R. Establishing MIC breakpoints and the interpretation of in vitro susceptibility tests.. J Antimicrob Chemother 2001 Jul;48 Suppl 1:17-28.
    pubmed: 11420334doi: 10.1093/jac/48.suppl_1.17google scholar: lookup
  2. Schwarz S, Silley P, Simjee S, Woodford N, van Duijkeren E, Johnson AP, Gaastra W. Editorial: assessing the antimicrobial susceptibility of bacteria obtained from animals.. J Antimicrob Chemother 2010 Apr;65(4):601-4.
    pubmed: 20181573doi: 10.1093/jac/dkq037google scholar: lookup
  3. Magdesian KG, Hogan PM, Cohen ND, Brumbaugh GW, Bernard WV. Pharmacokinetics of a high dose of gentamicin administered intravenously or intramuscularly to horses.. J Am Vet Med Assoc 1998 Oct 1;213(7):1007-11.
    pubmed: 9776999
  4. Tudor RA, Papich MG, Redding WR. Drug disposition and dosage determination of once daily administration of gentamicin sulfate in horses after abdominal surgery.. J Am Vet Med Assoc 1999 Aug 15;215(4):503-6.
    pubmed: 10461634
  5. Moore RD, Lietman PS, Smith CR. Clinical response to aminoglycoside therapy: importance of the ratio of peak concentration to minimal inhibitory concentration.. J Infect Dis 1987 Jan;155(1):93-9.
    pubmed: 3540140doi: 10.1093/infdis/155.1.93google scholar: lookup
  6. Kashuba AD, Nafziger AN, Drusano GL, Bertino JS Jr. Optimizing aminoglycoside therapy for nosocomial pneumonia caused by gram-negative bacteria.. Antimicrob Agents Chemother 1999 Mar;43(3):623-9.
    pmc: PMC89170pubmed: 10049277doi: 10.1128/aac.43.3.623google scholar: lookup
  7. Roberts JA, Norris R, Paterson DL, Martin JH. Therapeutic drug monitoring of antimicrobials.. Br J Clin Pharmacol 2012 Jan;73(1):27-36.
    pmc: PMC3248253pubmed: 21831196doi: 10.1111/j.1365-2125.2011.04080.xgoogle scholar: lookup
  8. Bauquier JR, Boston RC, Sweeney RW, Wilkins PA, Nolen-Walston RD. Plasma Peak and Trough Gentamicin Concentrations in Hospitalized Horses Receiving Intravenously Administered Gentamicin.. J Vet Intern Med 2015 Nov-Dec;29(6):1660-6.
    pmc: PMC4895685pubmed: 26426540doi: 10.1111/jvim.13626google scholar: lookup
  9. Dowling PM. Therapeutic drug monitoring. Equine Internal Medicine 3rd ed. St. Louis, MO: Saunders Elsevier; 2010:161–164.
  10. nClinical Laboratory Standards Institute (CLSI)n. VET01S, 3rd edition. Performance standards for antimicrobial disk and dilution susceptibility tests for bacteria isolated from animals; second informational supplement. 2015. nhttp://shop.clsi.org/veterinary-medicine-documents/. Accessed February 2, 2018.n
  11. nEuropean Committee on Antimicrobial Susceptibility Testing (EUCAST)n. Breakpoint tables for interpretation of MICs and zone diameters, version 5.0. 2015. nhttp://www.eucast.org/fileadmin/src/media/PDFs/EUCAST_files/Breakpoint_tables/v_5.0_Breakpoint_Table_01.pdf. Accessed February 2, 2018.n
  12. nClinical Laboratory Standards Institute (CLSI)n. VET05‐R. Generation, application and presentation of antimicrobial susceptibility test data for bacteria of animal origin; a report. 2011. nhttp://shop.clsi.org/veterinary-medicine-documents/. Accessed February 2, 2018.n
  13. nEuropean Committee on Antimicrobial Susceptibility Testing (EUCAST)n. Setting breakpoints for new antimicrobial agents. EUCAST SOP 1.1. 2013. nhttp://www.eucast.org/fileadmin/src/media/PDFs/EUCAST_files/EUCAST_SOPs/EUCAST_SOP_1._1_Setting_breakpoints_new_agents_1_June_2013.pdf. Accessed February 2, 2018.n
  14. Levison ME, Levison JH. Pharmacokinetics and pharmacodynamics of antibacterial agents.. Infect Dis Clin North Am 2009 Dec;23(4):791-815, vii.
    pmc: PMC3675903pubmed: 19909885doi: 10.1016/j.idc.2009.06.008google scholar: lookup
  15. Brown MP, Stover SM, Kelly RH, Farver TB. Gentamicin sulfate in the horse: serum, synovial, peritoneal, and urine concentrations after single dose intramuscular administration.. J Vet Pharmacol Ther 1982 Jun;5(2):119-22.
    pubmed: 7109023doi: 10.1111/j.1365-2885.1982.tb00506.xgoogle scholar: lookup
  16. McKenzie HC 3rd, Murray MJ. Concentrations of gentamicin in serum and bronchial lavage fluid after once-daily aerosol administration to horses for seven days.. Am J Vet Res 2004 Feb;65(2):173-8.
    pubmed: 14974574doi: 10.2460/ajvr.2004.65.173google scholar: lookup
  17. Blaser J, Simmen HP, Gonzenbach HR, Sonnabend W, Lüthy R. Aminoglycoside monitoring: timing of peak levels is critical.. Ther Drug Monit 1985;7(3):303-7.
    pubmed: 4049468
  18. Sweeney RW, Divers TJ, Rossier Y. Disposition of gentamicin administered intravenously to horses with sepsis.. J Am Vet Med Assoc 1992 Feb 15;200(4):503-6.
    pubmed: 1559887
  19. Burrows GE, Morton RJ, Fales WH. Microdilution antimicrobial susceptibilities of selected gram-negative veterinary bacterial isolates.. J Vet Diagn Invest 1993 Oct;5(4):541-7.
    pubmed: 8286452doi: 10.1177/104063879300500407google scholar: lookup
  20. Albihn A, Båverud V, Magnusson U. Uterine microbiology and antimicrobial susceptibility in isolated bacteria from mares with fertility problems.. Acta Vet Scand 2003;44(3-4):121-9.
    pmc: PMC1831563pubmed: 15074625doi: 10.1186/1751-0147-44-121google scholar: lookup
  21. McCormack JP, Jewesson PJ. A critical reevaluation of the "therapeutic range" of aminoglycosides.. Clin Infect Dis 1992 Jan;14(1):320-39.
    pubmed: 1571447doi: 10.1093/clinids/14.1.320google scholar: lookup
  22. Freeman CD, Nicolau DP, Belliveau PP, Nightingale CH. Once-daily dosing of aminoglycosides: review and recommendations for clinical practice.. J Antimicrob Chemother 1997 Jun;39(6):677-86.
    pubmed: 9222035doi: 10.1093/jac/39.6.677google scholar: lookup
  23. Jiang M, Karasawa T, Steyger PS. Aminoglycoside-Induced Cochleotoxicity: A Review.. Front Cell Neurosci 2017;11:308.
    pmc: PMC5640705pubmed: 29062271doi: 10.3389/fncel.2017.00308google scholar: lookup
  24. Ensink JM, van Klingeren B, Houwers DJ, Klein WR, Vulto AG. In-vitro susceptibility to antimicrobial drugs of bacterial isolates from horses in The Netherlands.. Equine Vet J 1993 Jul;25(4):309-13.
    pubmed: 8354217doi: 10.1111/j.2042-3306.1993.tb02969.xgoogle scholar: lookup
  25. Ahmed MO, Clegg PD, Williams NJ, Baptiste KE, Bennett M. Antimicrobial resistance in equine faecal Escherichia coli isolates from North West England.. Ann Clin Microbiol Antimicrob 2010 Apr 7;9:12.
    pmc: PMC2867969pubmed: 20374640doi: 10.1186/1476-0711-9-12google scholar: lookup
  26. Wilson DW. Rational selection of antimicrobials for use in horses. Proceedings of the 47th Annual Convention of the American Association of Equine Practitioners (AAEP) Vol. 47; 2001; November, San Diego, CA:75–93.
  27. Theelen MJ, Wilson WD, Edman JM, Magdesian KG, Kass PH. Temporal trends in in vitro antimicrobial susceptibility patterns of bacteria isolated from foals with sepsis: 1979-2010.. Equine Vet J 2014 Mar;46(2):161-8.
    pubmed: 23808791doi: 10.1111/evj.12130google scholar: lookup
  28. Piette A, Verschraegen G. Role of coagulase-negative staphylococci in human disease.. Vet Microbiol 2009 Feb 16;134(1-2):45-54.
    pubmed: 18986783doi: 10.1016/j.vetmic.2008.09.009google scholar: lookup

Citations

This article has been cited 5 times.
  1. Bookbinder LC, Mani R, Carr EA. Antibiograms of field and hospital acquired equine neonatal bacterial fluid cultures in the Midwestern United States: 149 samples (2007-2018).. J Vet Intern Med 2023 May-Jun;37(3):1193-1200.
    doi: 10.1111/jvim.16671pubmed: 37029453google scholar: lookup
  2. LuTheryn G, Hind C, Campbell C, Crowther A, Wu Q, Keller SB, Glynne-Jones P, Sutton JM, Webb JS, Gray M, Wilks SA, Stride E, Carugo D. Bactericidal and anti-biofilm effects of uncharged and cationic ultrasound-responsive nitric oxide microbubbles on Pseudomonas aeruginosa biofilms.. Front Cell Infect Microbiol 2022;12:956808.
    doi: 10.3389/fcimb.2022.956808pubmed: 35992170google scholar: lookup
  3. Aleman MR, True A, Scalco R, Crowe CM, Costa LRR, Chigerwe M. Gentamicin-induced sensorineural auditory loss in healthy adult horses.. J Vet Intern Med 2021 Sep;35(5):2486-2494.
    doi: 10.1111/jvim.16221pubmed: 34322916google scholar: lookup
  4. Redpath A, Hallowell GD, Bowen IM. Use of aminoglycoside antibiotics in equine clinical practice; a questionnaire-based study of current use.. Vet Med Sci 2021 Mar;7(2):279-288.
    doi: 10.1002/vms3.382pubmed: 33099884google scholar: lookup
  5. Potier JFN, Durham AE. Antimicrobial susceptibility of bacterial isolates from ambulatory practice and from a referral hospital.. J Vet Intern Med 2020 Jan;34(1):300-306.
    doi: 10.1111/jvim.15685pubmed: 31849110google scholar: lookup
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