1. Oxytetracycline concentrations in interstitial fluid from tissue chambers inoculated with Corynebacterium pseudotuberculosis after intramuscular or intrachamber administration in sheep.
- Author
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Washburn KE, Fajt VR, Polasek AN, Lawhon SD, Padgett AL, Lo CP, Mays TP, and Washburn SE
- Subjects
- Abscess drug therapy, Abscess prevention & control, Abscess veterinary, Animals, Anti-Bacterial Agents pharmacokinetics, Anti-Bacterial Agents therapeutic use, Corynebacterium Infections metabolism, Corynebacterium Infections prevention & control, Disease Models, Animal, Extracellular Fluid metabolism, Female, Lymphadenitis drug therapy, Lymphadenitis veterinary, Oxytetracycline pharmacokinetics, Oxytetracycline therapeutic use, Random Allocation, Sheep, Sheep Diseases prevention & control, Anti-Bacterial Agents administration & dosage, Corynebacterium Infections veterinary, Corynebacterium pseudotuberculosis, Injections, Intralesional veterinary, Injections, Intramuscular veterinary, Oxytetracycline administration & dosage, Sheep Diseases drug therapy
- Abstract
Objective: To determine oxytetracycline concentrations in plasma and in fluid from Corynebacterium pseudotuberculosis (CPT)-inoculated tissue chambers (used as experimental abscess models) and uninoculated (control) tissue chambers in sheep after IM or local administration of the drug and to investigate whether CPT growth was reduced or eliminated by these treatments., Animals: 10 clinically normal female sheep., Procedures: Sterile tissue chambers were surgically implanted in both paralumbar fossae of each sheep; ≥ 2 weeks later (day -6), 1 randomly selected chamber was inoculated with CPT, and the opposite chamber was injected with sterile growth medium. Sheep received oxytetracycline IM (n = 5) or by percutaneous injection into CPT-inoculated (4) or uninoculated (1) chambers on day 0. Tissue fluid from each chamber and venous blood samples for plasma collection were obtained at predetermined times over 6 days for bacterial counts (tissue chambers) and analysis of oxytetracycline concentrations (tissue chambers and plasma). Sheep were euthanized on day 6. Regional lymph nodes were collected bilaterally from each sheep for culture., Results: Measurable concentrations of oxytetracycline were present in each chamber throughout the study, regardless of administration route or presence of CPT. No CPT growth was detected after the 48-hour time point in inoculated chambers injected with oxytetracycline; however, CPT was isolated from all inoculated chambers throughout the study after IM drug administration. One regional lymph node (ipsilateral to a CPT-inoculated, oxytetracycline-injected chamber with no CPT growth after 48 hours) was culture positive for CPT., Conclusions and Clinical Relevance: Intralesional administration of oxytetracycline may eliminate growth of CPT locally, but complete elimination of the organism remains difficult.
- Published
- 2019
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