Minimum Inhibitory Concentrations of Equine Corynebacterium pseudotuberculosis Isolates (1996–2012). (14th January 2015)

• Record Type: Journal Article
• Authors: Rhodes, D.M.; Magdesian, K.G.; Byrne, B.A.; Kass, P.H.; Edman, J.; Spier, S.J.
• Is Part Of: Journal of veterinary internal medicine. Volume 29:Number 1(2015:Jan./Feb.)
• Page Start: 327
• Page End: 332
• Publication Date: 2015-01-14
• Subjects: Veterinary medicine -- Periodicals; 636.0896
• DOI: 10.1111/jvim.12534
• Languages: English
• ISSNs: 0891-6640

Abstract

<abstract abstract-type="main" id="jvim12534-abs-0001"> <title> <x xml:space="preserve">Abstract</x> </title> <sec id="jvim12534-sec-0001" sec-type="section"> <title>Background</title> <p>Few studies report the minimum inhibitory concentrations for antimicrobials against equine <italic>Corynebacterium pseudotuberculosis</italic> isolates.</p> </sec> <sec id="jvim12534-sec-0002" sec-type="section"> <title>Hypothesis/Objectives</title> <p>To evaluate trends in the in vitro activities of 20 antimicrobials against equine <italic>Corynebacterium pseudotuberculosis</italic> isolates from 1996 to 2012 and to determine if a relationship exists between the minimum inhibitory concentration (MIC) and location of the abscess.</p> </sec> <sec id="jvim12534-sec-0003" sec-type="section"> <title>Animals</title> <p> <italic>Corynebacterium pseudotuberculosis</italic> isolates from 196 horses with naturally occurring disease.</p> </sec> <sec id="jvim12534-sec-0004" sec-type="section"> <title>Methods</title> <p>Retrospective and cross‐sectional design. Medical records were reviewed to obtain clinical and MIC data. Minimum inhibitory concentrations were determined by the microdilution technique. The MIC results over 3 periods were compared (1996–2001, 2002–2006, 2007–2012).</p> </sec> <sec id="jvim12534-sec-0005" sec-type="section"> <title>Results</title> <p>The MIC<sub>90</sub> values for clinically relevant antimicrobials were as follows: chloramphenicol ≤4 μg/mL, enrofloxacin ≤0.25 μg/mL, gentamicin ≤1 μg/mL, penicillin =0.25 μg/mL, rifampin ≤1 μg/mL, tetracycline ≤2 μg/mL, trimethoprim‐sulfamethoxazole (TMS) ≤0.5 μg/mL, ceftiofur =2 μg/mL, and doxycycline ≤2 μg/mL. There were no significant changes in MIC results over the study period. There was no relationship between MIC patterns and abscess location.</p> </sec> <sec id="jvim12534-sec-0006" sec-type="section"> <title>Conclusions and Clinical Importance</title> <p>The MIC<sub>50</sub> and MIC<sub>90</sub> values of antimicrobials evaluated in this study for equine isolates of <italic>C. pseudotuberculosis</italic> did not vary over time. Abscess location was not associated with different MIC patterns in cultured isolates. Several commonly used antimicrobials are active in vitro against <italic>C. pseudotuberculosis</italic> in vitro.</p> </sec> </abstract>