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Zúñiga MP, Badillo E, Abalos P, Valencia ED, Marín P, Escudero E, Galecio JS. Antimicrobial susceptibility of Rhodococcus equi strains isolated from foals in Chile. World J Microbiol Biotechnol 2023; 39:231. [PMID: 37347336 PMCID: PMC10287571 DOI: 10.1007/s11274-023-03677-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Accepted: 06/12/2023] [Indexed: 06/23/2023]
Abstract
Rhodococcus equi is responsible for foal pneumonia worldwide, with a significant economic impact on the production and breeding of horses. In Chile, the first case was reported in 2000, and since then, its incidence has been increasing. Distinctive characteristics of R. equi as an intracellular pathogen in macrophages, emergence of virulence plasmids encoding surface lipoprotein antigens, and appearance of antibiotic resistance against macrolides and rifampicin have significantly complicated the treatment of R. equi pneumonia in foals. Therefore, in vitro susceptibility studies of first-line and newer antibiotics against R. equi are the first step to establishing effective treatments and optimizing new therapeutic options. The aim of the present study is to determine the susceptibility profile of fourteen strains of R. equi isolated from foals in Chile to several antibiotics of the macrolide group including azithromycin, amikacin, tildipirosin and gamithromycin as well as others such as rifampicin, doxycycline and ceftiofur. Identification of R. equi in collected isolates from foals in Chile has been performed by CAMP test and PCR based on detecting of the gene encoding the 16 S rRNA. The presence of genes encoding virulence plasmids was also determined using PCR. Results obtained have demonstrated presence of virulent R. equi strains in Chile. In vitro susceptibility pattern to different antibiotics has shown better results for doxycycline and rifampicin similar to previous studies performed. Current macrolides have been evaluated in order to consider alternative treatment options in a context of emerging resistance to classic macrolides and rifampicin, obtaining better results with gamithromycin (MIC range of 0.125 to 128 mg/ml) than with tildipirosin (MIC range of 16 to 128 mg/ml). An adequate diagnosis of bacterial susceptibility based on antibiograms is necessary to treat the Rhodococcus equi infection in foals.
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Affiliation(s)
- María Paz Zúñiga
- Facultad de Agronomía y Veterinaria, Universidad Nacional de Rio Cuarto, Córdova, Argentina
- Escuela de Medicina Veterinaria, Facultad de Ciencias, Universidad Mayor, Santiago de Chile, Chile
| | - Elena Badillo
- Department of Pharmacology, Faculty of Veterinary Medicine, University of Murcia, Murcia, 30100, Spain
| | - Pedro Abalos
- Facultad de Ciencias Veterinarias y Pecuarias, Universidad de Chile, La Pintana, 8820808, Chile
| | - Eduardo David Valencia
- Instituto de Microbiología, Colegio de Ciencias Biológicas y Ambientales, Universidad San Francisco de Quito, Quito, EC, 170157, Ecuador
| | - Pedro Marín
- Department of Pharmacology, Faculty of Veterinary Medicine, University of Murcia, Murcia, 30100, Spain
| | - Elisa Escudero
- Department of Pharmacology, Faculty of Veterinary Medicine, University of Murcia, Murcia, 30100, Spain
| | - Juan Sebastian Galecio
- Department of Pharmacology, Faculty of Veterinary Medicine, University of Murcia, Murcia, 30100, Spain.
- Colegio de Ciencias de la Salud, Escuela de Medicina Veterinaria, Universidad San Francisco de Quito, Quito, EC, 170157, Ecuador.
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Wang J, Zhou X, Elazab ST, Park SC, Hsu WH. Should Airway Interstitial Fluid Be Used to Evaluate the Pharmacokinetics of Macrolide Antibiotics for Dose Regimen Determination in Respiratory Infection? Antibiotics (Basel) 2023; 12:antibiotics12040700. [PMID: 37107062 PMCID: PMC10135031 DOI: 10.3390/antibiotics12040700] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2023] [Revised: 03/07/2023] [Accepted: 03/08/2023] [Indexed: 04/07/2023] Open
Abstract
Macrolide antibiotics are important drugs to combat infections. The pharmacokinetics (PK) of these drugs are essential for the determination of their optimal dose regimens, which affect antimicrobial pharmacodynamics and treatment success. For most drugs, the measurement of their concentrations in plasma/serum is the surrogate for drug concentrations in target tissues for therapy. However, for macrolides, simple reliance on total or free drug concentrations in serum/plasma might be misleading. The macrolide antibiotic concentrations of serum/plasma, interstitial fluid (ISF), and target tissue itself usually yield very different PK results. In fact, the PK of a macrolide antibiotic based on serum/plasma concentrations alone is not an ideal predictor for the in vivo efficacy against respiratory pathogens. Instead, the PK based on drug concentrations at the site of infection or ISF provide much more clinically relevant information than serum/plasma concentrations. This review aims to summarize and compare/discuss the use of drug concentrations of serum/plasma, airway ISF, and tissues for computing the PK of macrolides. A better understanding of the PK of macrolide antibiotics based on airway ISF concentrations will help optimize the antibacterial dose regimen as well as minimizing toxicity and the emergence of drug resistance in clinical practice.
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Affiliation(s)
- Jianzhong Wang
- Shanxi Key Laboratory for Modernization of TCVM, College of Veterinary Medicine, Shanxi Agricultural University, Taigu, Jinzhong 030810, China
| | - Xueying Zhou
- Department of Veterinary Clinical Science, College of Veterinary Medicine, China Agricultural University, Beijing 100107, China
| | - Sara T. Elazab
- Department of Pharmacology, Faculty of Veterinary Medicine, Mansoura University, El-Mansoura 35516, Egypt
| | - Seung-Chun Park
- Laboratory of Veterinary Pharmacokinetics and Pharmacodynamics, College of Veterinary Medicine, Kyungpook National University, Daegu 41566, Republic of Korea
| | - Walter H. Hsu
- Department of Biomedical Sciences, College of Veterinary Medicine, Iowa State University, Ames, IA 50011-2042, USA
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PK-PD Modeling and Optimal Dosing Regimen of Acetylkitasamycin against Streptococcus suis in Piglets. Antibiotics (Basel) 2022; 11:antibiotics11020283. [PMID: 35203885 PMCID: PMC8868236 DOI: 10.3390/antibiotics11020283] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Revised: 02/16/2022] [Accepted: 02/19/2022] [Indexed: 02/04/2023] Open
Abstract
Streptococcus suis (S. suis) causes severe respiratory diseases in pigs and is also an important pathogen causing hidden dangers to public health and safety. Acetylkitasamycin is a new macrolide agent that has shown good activity to Gram-positive cocci such as Streptococcus. The purpose of this study was to perform pharmacokinetic–pharmacodynamic (PK-PD) modeling to formulate a dosing regimen of acetylkitasamycin for treatment of S. suis and to decrease the emergence of acetylkitasamycin-resistant S. suis. The minimal inhibitory concentration (MIC) of 110 S. suis isolates was determined by broth micro dilution method. The MIC50 of the 55 sensitive S. suis isolates was 1.21 μg/mL. The strain HB1607 with MIC close to MIC50 and high pathogenicity was used for the PK-PD experiments. The MIC and MBC of HB1607 in both MH broth and pulmonary epithelial lining fluid (PELF) was 1 and 2 μg/mL, respectively. The liquid chromatography–tandem mass spectrometry (LC-MS/MS) method was used to determine the concentration change of acetylkitasamycin in piglet plasma and PELF after intragastric administration of a single dose of 50 mg/kg b.w. acetylkitasamycin. The PK parameters were calculated by WinNolin software. The PK data showed that the maximum concentration (Cmax), peak time (Tmax), and area under the concentration–time curve (AUC) were 9.84 ± 0.39 μg/mL, 4.27 ± 0.19 h and 248.58 ± 21.17 h·μg/mL, respectively. Integration of the in vivo PK data and ex vivo PD data, an inhibition sigmoid Emax equation was established. The dosing regimen of acetylkitasamycin for the treatment S. suis infection established as 33.12 mg/kg b.w. every 12 h for 3 days. This study provided a reasonable dosing regimen for a new drug used in clinical treatment, which can effectively be used to treat S. suis infection and slow down the generation of drug resistance.
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Bordin AI, Huber L, Sanz M, Cohen N. Rhodococcus equi Foal Pneumonia: Update on Epidemiology, Immunity, Treatment, and Prevention. Equine Vet J 2022; 54:481-494. [PMID: 35188690 DOI: 10.1111/evj.13567] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Revised: 02/03/2022] [Accepted: 02/17/2022] [Indexed: 11/25/2022]
Abstract
Pneumonia in foals caused by the bacterium Rhodococcus equi has a worldwide distribution and is a common cause of disease and death for foals. The purpose of this narrative review is to summarise recent developments pertaining to the epidemiology, immune responses, treatment, and prevention of rhodococcal pneumonia of foals. Screening tests have been used to implement earlier detection and treatment of foals with presumed subclinical R. equi pneumonia to reduce mortality and severity of disease. Unfortunately, this practice has been linked to the emergence of antimicrobial resistant R. equi in North America. Correlates of protective immunity for R. equi infections of foals remain elusive, but recent evidence indicates that innate immune responses are important both for mediating killing and orchestrating adaptive immune responses. A macrolide antimicrobial in combination with rifampin remains the recommended treatment for foals with R. equi pneumonia. Great need exists to identify which antimicrobial combination is most effective for treating foals with R. equi pneumonia and to limit emergence of antimicrobial-resistant strains. In the absence of an effective vaccine against R. equi, passive immunisation remains the only commercially-available method for effectively reducing the incidence of R. equi pneumonia. Because passive immunisation is expensive, labour-intensive, and carries risks for foals, great need exists to develop alternative approaches for passive and active immunisation.
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Affiliation(s)
- Angela I Bordin
- Equine Infectious Disease Laboratory, Department of Large Animal Clinical Sciences, College of Veterinary Medicine & Biomedical Sciences, Texas A&M University, College Station, Texas, 77843-4475, USA
| | - Laura Huber
- Department of Pathobiology, College of Veterinary Medicine, Auburn University, Auburn, Alabama, 36849, USA
| | - Macarena Sanz
- Department of Veterinary Clinical Sciences, College of Veterinary Medicine, Washington State University, Pullman, Washington, 99164-6610, USA
| | - Noah Cohen
- Equine Infectious Disease Laboratory, Department of Large Animal Clinical Sciences, College of Veterinary Medicine & Biomedical Sciences, Texas A&M University, College Station, Texas, 77843-4475, USA
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Erol E, Shaffer CL, Lubbers BV. Synergistic combinations of clarithromycin with doxycycline or minocycline reduce the emergence of antimicrobial resistance in Rhodococcus equi. Equine Vet J 2021; 54:799-806. [PMID: 34480367 DOI: 10.1111/evj.13508] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Revised: 07/08/2021] [Accepted: 08/27/2021] [Indexed: 12/28/2022]
Abstract
BACKGROUND The alarming increase in rifampin and macrolide resistance among Rhodococcus equi isolates highlights the need to identify alternative therapeutic options that can effectively control rhodococcosis in foals while limiting the further development of drug resistance. OBJECTIVES To evaluate bacterial killing, antibiotic synergism and mutant prevention concentrations (MPCs) of clarithromycin alone and in combination with doxycycline, minocycline or rifampin against clinical isolates of R equi. STUDY DESIGN In vitro experiments. METHODS Bacterial time-kill, fractional inhibitory concentration (checkerboard) and mutant prevention concentration assays were evaluated in four clarithromycin- and rifampin-susceptible (ClaS /RifS ) and two clarithromycin- and rifampin-resistant (ClaR /RifR ) R equi clinical strains. RESULTS In this study evaluating a limited number of isolates, combinations of clarithromycin with doxycycline or minocycline, but not with rifampin, were generally synergistic in both ClaS /RifS and ClaR /RifR strains as determined by checkerboard testing. In time-kill assays, all antibiotics, both alone and in combination, reduced viable ClaS /RifS R equi by more than 3 log10 at 24 hours compared with control cultures without antibiotics. Combinations of clarithromycin with doxycycline, minocycline or rifampin induced significantly lower MPC values compared with the individual antimicrobials alone for all ClaS /RifS R equi strains, resulting in a narrower mutant selection window (MSW). However, clarithromycin/rifampin combination did not markedly decrease MPCs of the individual antimicrobials in ClaR /RifR R equi isolates, and the observed decrease in MPCs for doxycycline or minocycline did not generally differ when combined with clarithromycin. MAIN LIMITATIONS The number of analysed R equi isolates was limited. In vitro outcomes require clinical confirmation. CONCLUSIONS Dual therapy combinations consisting of clarithromycin with doxycycline or minocycline merit consideration as a treatment protocol against R equi in foals due to in vitro synergy. These combination therapies may also minimise the emergence of antimicrobial resistance in cases of rhodococcosis.
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Affiliation(s)
- Erdal Erol
- Department of Veterinary Science and the Veterinary Diagnostic Laboratory, University of Kentucky, Lexington, KY, USA
| | - Carrie L Shaffer
- Department of Veterinary Science and the Gluck Equine Research Center, University of Kentucky, Lexington, KY, USA
| | - Brian V Lubbers
- Department of Clinical Sciences, Kansas State University, Manhattan, KS, USA
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Leventhal HR, McKenzie HC, Estell K, Council-Troche M, Davis JL. Pharmacokinetics and pulmonary distribution of Draxxin ® (tulathromycin) in healthy adult horses. J Vet Pharmacol Ther 2021; 44:714-723. [PMID: 33719056 DOI: 10.1111/jvp.12968] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Revised: 10/27/2020] [Accepted: 02/27/2021] [Indexed: 11/28/2022]
Abstract
The objective of this study was to determine the pharmacokinetics and tolerability of tulathromycin (Draxxin® ; 2.5 mg/kg once) after intramuscular (IM), subcutaneous (SC), and slow intravenous (IV) administration to six adult horses. A three-phase design and 4-week washout period were used. Drug concentrations in blood and bronchoalveolar lavage (BAL) samples were determined by ultra-performance liquid chromatography tandem mass spectrometry and pharmacokinetic parameters calculated using noncompartmental analysis. Following SC and IM administration, all horses exhibited sweating, discomfort, and periods of recumbency. As signs were more severe after SC administration this route was only used in 3/6 horses. Intravenous administration of tulathromycin was well tolerated in all horses. Mean bioavailability was 99.4% IM and 115% SC. Mean maximum plasma concentration was 645 ng/ml IM and 373 ng/ml SC. Mean half-life was 59.8 h, 54.8 h, and 57.9 h for IV, IM, and SC administration, respectively. Mean clearance was 3.25 ml/kg/min, and mean volume of distribution was 16.8 L/kg following IV administration. Drug was detectable in plasma and BAL samples for 120 h following all routes; however, adverse effects may prevent IM use and SC use is not recommended. Tulathromycin may be a practical and affordable antimicrobial for use in adult equine patients.
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Affiliation(s)
- Hannah R Leventhal
- Department of Large Animal Clinical Sciences, Virginia-Maryland College of Veterinary Medicine, Blacksburg, VA, USA
| | - Harold C McKenzie
- Department of Large Animal Clinical Sciences, Virginia-Maryland College of Veterinary Medicine, Blacksburg, VA, USA
| | - Krista Estell
- Marion duPont Scott Equine Medical Center, Virginia-Maryland College of Veterinary Medicine, Leesburg, VA, USA
| | - McAlister Council-Troche
- Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Blacksburg, VA, USA
| | - Jennifer L Davis
- Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Blacksburg, VA, USA
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Bielas R, Siewniak A, Skonieczna M, Adamiec M, Mielańczyk Ł, Neugebauer D. Choline based polymethacrylate matrix with pharmaceutical cations as co-delivery system for antibacterial and anti-inflammatory combined therapy. J Mol Liq 2019. [DOI: 10.1016/j.molliq.2019.04.082] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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9
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Giguère S, Cohen ND. Controversies in therapy of infections caused byRhodococcus equiin foals. EQUINE VET EDUC 2017. [DOI: 10.1111/eve.12870] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- S. Giguère
- University of Georgia; Athens Georgia USA
| | - N. D. Cohen
- Texas A&M University; College Station Texas USA
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Giguère S. Treatment of Infections Caused by Rhodococcus equi. Vet Clin North Am Equine Pract 2017; 33:67-85. [DOI: 10.1016/j.cveq.2016.11.002] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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11
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Berlin S, Randow T, Scheuch E, Grube M, Venner M, Siegmund W. Pharmacokinetics and pulmonary distribution of gamithromycin after intravenous administration in foals. J Vet Pharmacol Ther 2017; 40:406-410. [DOI: 10.1111/jvp.12402] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2016] [Accepted: 02/14/2017] [Indexed: 01/29/2023]
Affiliation(s)
- S. Berlin
- Department of Clinical Pharmacology; Center of Drug Absorption and Transport (C_DAT); University Medicine of Greifswald; Greifswald Germany
| | | | - E. Scheuch
- Department of Clinical Pharmacology; Center of Drug Absorption and Transport (C_DAT); University Medicine of Greifswald; Greifswald Germany
| | - M. Grube
- Department of General Pharmacology; Center of Drug Absorption and Transport (C_DAT); University Medicine of Greifswald; Greifswald Germany
| | - M. Venner
- Veterinary Clinic for Horses; Destedt Germany
| | - W. Siegmund
- Department of Clinical Pharmacology; Center of Drug Absorption and Transport (C_DAT); University Medicine of Greifswald; Greifswald Germany
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12
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Acosta EP, Grigsby PL, Larson KB, James AM, Long MC, Duffy LB, Waites KB, Novy MJ. Transplacental transfer of Azithromycin and its use for eradicating intra-amniotic ureaplasma infection in a primate model. J Infect Dis 2014; 209:898-904. [PMID: 24179112 PMCID: PMC3935474 DOI: 10.1093/infdis/jit578] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2013] [Accepted: 09/20/2013] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Our goals were to describe azithromycin (AZI) pharmacokinetics in maternal plasma (MP), fetal plasma (FP), and amniotic fluid (AF) following intra-amniotic infection (IAI) with Ureaplasma in pregnant rhesus monkeys and to explore concentration-response relationships. METHODS Following intra-amniotic inoculation of Ureaplasma parvum, rhesus monkeys received AZI (12.5 mg/kg every 12 hours intravenously for 10 days; n = 10). Intensive pharmacokinetic sampling of MP, FP, and AF was scheduled following the first (ie, single) dose and the last (ie, multiple) dose. Noncompartmental and pharmacokinetic modeling methods were used. RESULTS The AF area under the concentration-time curve at 12 hours was 0.22 µg×h/mL following a single dose and 6.3 µg×h/mL at day 10. MP and AF accumulation indices were 8.4 and 19, respectively. AZI AF half-life following the single dose and multiple dose were 156 and 129 hours, respectively. The median MP:FP ratio in concomitantly drawn samples was 3.2 (range, 1.3-9.6; n = 9). Eradication of U. parvum occurred at 6.6 days, with a 95% effective concentration (EC95) of 39 ng/mL for the maximum AZI AF concentration. CONCLUSIONS Our study demonstrates that a maternal multiple-dose AZI regimen is effective in eradicating U. parvum IAI by virtue of intra-amniotic accumulation and suggests that antenatal therapy has the potential to mitigate complications associated with U. parvum infection in pregnancy, such as preterm labor and fetal sequelae.
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Affiliation(s)
| | - Peta L. Grigsby
- Oregon National Primate Research Center
- Division of Reproductive and Developmental Sciences
- Department of Obstetrics and Gynecology, Oregon Health and Science University, Beaverton
| | | | | | | | - Lynn B. Duffy
- Department of Pathology, University of Alabama at Birmingham
| | - Ken B. Waites
- Department of Pathology, University of Alabama at Birmingham
| | - Miles J. Novy
- Oregon National Primate Research Center
- Division of Reproductive and Developmental Sciences
- Department of Obstetrics and Gynecology, Oregon Health and Science University, Beaverton
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Berghaus LJ, Giguère S, Guldbech K. Mutant prevention concentration and mutant selection window for 10 antimicrobial agents against Rhodococcus equi. Vet Microbiol 2013; 166:670-5. [PMID: 23915992 DOI: 10.1016/j.vetmic.2013.07.006] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2013] [Revised: 07/01/2013] [Accepted: 07/10/2013] [Indexed: 12/23/2022]
Abstract
The objectives of this study were to determine the mutant prevention concentration (MPC), time above the MPC and mutant selection window for 10 antimicrobial agents against Rhodococcus equi and to determine if the combination of a macrolide with rifampin would decrease emergence of resistant mutants. Antimicrobial agents investigated (erythromycin, clarithromycin, azithromycin, rifampin, amikacin, gentamicin, enrofloxacin, vancomycin, imipenem, and doxycycline) were selected based on in vitro activity and frequency of use in foals or people infected with R. equi. Each antimicrobial agent or combination of agents was evaluated against four virulent strains of R. equi. MPC were determined using an agar plate assay. Pharmacodynamic parameters were calculated using published plasma and pulmonary pharmacokinetic variables. There was a significant (P<0.001) effect of the type of antimicrobial agent on the MPC. The MPC of clarithromycin (1.0 μg/ml) was significantly lower and the MPC of rifampin and amikacin (512 and 384 μg/ml, respectively) were significantly higher than that of all other antimicrobial agents tested. Combining erythromycin, clarithromycin, or azithromycin with rifampin resulted in a significant (P≤0.005) decrease in MPC and MPC/MIC ratio. When MIC and MPC were combined with pharmacokinetic variables, only gentamicin and vancomycin were predicted to achieve plasma concentrations above the MPC for any given periods of time. Only clarithromycin and the combination clarithromycin-rifampin were predicted to achieve concentrations in bronchoalveolar cells and pulmonary epithelial lining fluid above the MPC for the entire dosing interval. In conclusion, the combination of a macrolide with rifampin considerably decreases the emergence of resistant mutants of R. equi.
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Affiliation(s)
- Londa J Berghaus
- Department of Large Animal Medicine, College of Veterinary Medicine, University of Georgia, Athens, GA 30602, USA
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Villarino N, Martín-Jiménez T. Pharmacokinetics of macrolides in foals. J Vet Pharmacol Ther 2012; 36:1-13. [DOI: 10.1111/jvp.12010] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2011] [Revised: 08/10/2012] [Accepted: 08/13/2012] [Indexed: 11/29/2022]
Affiliation(s)
- N. Villarino
- Department of Microbiology; University of Tennessee; Knoxville TN USA
| | - T. Martín-Jiménez
- Department of Biomedical and Diagnostic Sciences; College of Veterinary Medicine; University of Tennessee; Knoxville TN USA
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15
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Winther L. Antimicrobial drug concentrations and sampling techniques in the equine lung. Vet J 2012; 193:326-35. [DOI: 10.1016/j.tvjl.2012.02.010] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2011] [Revised: 02/16/2012] [Accepted: 02/17/2012] [Indexed: 10/28/2022]
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16
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Rodvold KA, George JM, Yoo L. Penetration of anti-infective agents into pulmonary epithelial lining fluid: focus on antibacterial agents. Clin Pharmacokinet 2012; 50:637-64. [PMID: 21895037 DOI: 10.2165/11594090-000000000-00000] [Citation(s) in RCA: 177] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
The exposure-response relationship of anti-infective agents at the site of infection is currently being re-examined. Epithelial lining fluid (ELF) has been suggested as the site (compartment) of antimicrobial activity against lung infections caused by extracellular pathogens. There have been an extensive number of studies conducted during the past 20 years to determine drug penetration into ELF and to compare plasma and ELF concentrations of anti-infective agents. The majority of these studies estimated ELF drug concentrations by the method of urea dilution and involved either healthy adult subjects or patients undergoing diagnostic bronchoscopy. Antibacterial agents such as macrolides, ketolides, newer fluoroquinolones and oxazolidinones have ELF to plasma concentration ratios of >1. In comparison, β-lactams, aminoglycosides and glycopeptides have ELF to plasma concentration ratios of ≤1. Potential explanations (e.g. drug transporters, overestimation of the ELF volume, lysis of cells) for why these differences in ELF penetration occur among antibacterial classes need further investigation. The relationship between ELF concentrations and clinical outcomes has been under-studied. In vitro pharmacodynamic models, using simulated ELF and plasma concentrations, have been used to examine the eradication rates of resistant and susceptible pathogens and to explain why selected anti-infective agents (e.g. those with ELF to plasma concentration ratios of >1) are less likely to be associated with clinical treatment failures. Population pharmacokinetic modelling and Monte Carlo simulations have recently been used and permit ELF and plasma concentrations to be evaluated with regard to achievement of target attainment rates. These mathematical modelling techniques have also allowed further examination of drug doses and differences in the time courses of ELF and plasma concentrations as potential explanations for clinical and microbiological effects seen in clinical trials. Further studies are warranted in patients with lower respiratory tract infections to confirm and explore the relationships between ELF concentrations, clinical and microbiological outcomes, and pharmacodynamic parameters.
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LECLERE M, MAGDESIAN KG, COLE CA, SZABO NJ, RUBY RE, RHODES DM, EDMAN J, VALE A, WILSON WD, TELL LA. Pharmacokinetics and preliminary safety evaluation of azithromycin in adult horses. J Vet Pharmacol Ther 2011; 35:541-9. [DOI: 10.1111/j.1365-2885.2011.01351.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Giguère S, Cohen ND, Chaffin MK, Slovis NM, Hondalus MK, Hines SA, Prescott JF. Diagnosis, treatment, control, and prevention of infections caused by Rhodococcus equi in foals. J Vet Intern Med 2011; 25:1209-20. [PMID: 22092608 DOI: 10.1111/j.1939-1676.2011.00835.x] [Citation(s) in RCA: 93] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2011] [Revised: 09/22/2011] [Accepted: 10/04/2011] [Indexed: 11/29/2022] Open
Abstract
Rhodococcus equi, a gram-positive facultative intracellular pathogen, is one of the most common causes of pneumonia in foals. Although R. equi can be cultured from the environment of virtually all horse farms, the clinical disease in foals is endemic at some farms, sporadic at others, and unrecognized at many. On farms where the disease is endemic, costs associated with morbidity and mortality attributable to R. equi may be very high. The purpose of this consensus statement is to provide recommendations regarding the diagnosis, treatment, control, and prevention of infections caused by R. equi in foals.
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Affiliation(s)
- S Giguère
- Department of Large Animal Medicine, University of Georgia, Athens, GA 30602, USA.
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CREDILLE BC, GIGUÈRE S, BERGHAUS LJ, BURTON AJ, STURGILL TL, GROVER GS, DONECKER JM, BROWN SA. Plasma and pulmonary disposition of ceftiofur and its metabolites after intramuscular administration of ceftiofur crystalline free acid in weanling foals. J Vet Pharmacol Ther 2011; 35:259-64. [DOI: 10.1111/j.1365-2885.2011.01311.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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BERGHAUS LJ, GIGUÈRE S, STURGILL TL, BADE D, MALINSKI TJ, HUANG R. Plasma pharmacokinetics, pulmonary distribution, and in vitro activity of gamithromycin in foals. J Vet Pharmacol Ther 2011; 35:59-66. [DOI: 10.1111/j.1365-2885.2011.01292.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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JAVSICAS LH, GIGUÈRE S, WOMBLE ARIELY. Disposition of oral telithromycin in foals andin vitroactivity of the drug against macrolide-susceptible and macrolide-resistantRhodococcus equiisolates. J Vet Pharmacol Ther 2010; 33:383-8. [DOI: 10.1111/j.1365-2885.2009.01151.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Chaffin MK, Cohen ND, Martens RJ. Chemoprophylactic effects of azithromycin againstRhodococcus equi–induced pneumonia among foals at equine breeding farms with endemic infections. J Am Vet Med Assoc 2008; 232:1035-47. [DOI: 10.2460/javma.232.7.1035] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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