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Marsella R, White S, Fadok VA, Wilson D, Mueller R, Outerbridge C, Rosenkrantz W. Equine allergic skin diseases: Clinical consensus guidelines of the World Association for Veterinary Dermatology. Vet Dermatol 2023; 34:175-208. [PMID: 37154488 DOI: 10.1111/vde.13168] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2022] [Revised: 02/03/2023] [Accepted: 02/26/2023] [Indexed: 05/10/2023]
Abstract
BACKGROUND Allergic skin diseases are common in horses worldwide. The most common causes are insect bites and environmental allergens. OBJECTIVES To review the current literature and provide consensus on pathogenesis, diagnosis, treatment and prevention. MATERIALS AND METHODS The authors reviewed the literature up to November 2022. Results were presented at North America Veterinary Dermatology Forum (2021) and European Veterinary Dermatology Congress (2021). The report was available to member organisations of the World Association for Veterinary Dermatology for feedback. CONCLUSIONS AND CLINICAL RELEVANCE Insect bite hypersensitivity (IBH) is the best characterised allergic skin disease. An immunoglobulin (Ig)E response against Culicoides salivary antigens is widely documented. Genetics and environmental factors play important roles. Tests with high sensitivity and specificity are lacking, and diagnosis of IBH is based on clinical signs, seasonality and response to insect control. Eosinophils, interleukin (IL)-5 and IL-31 are explored as therapeutic targets. Presently, the most effective treatment is insect avoidance. Existing evidence does not support allergen-specific immunotherapy (ASIT) using commercially available extracts of Culicoides. Hypersensitivity to environmental allergens (atopic dermatitis) is the next most common allergy. A role for IgE is supported by serological investigation, skin test studies and positive response to ASIT. Prospective, controlled, randomised studies are limited, and treatment relies largely on glucocorticoids, antihistamines and ASIT based on retrospective studies. Foods are known triggers for urticaria, yet their role in pruritic dermatitis is unknown. Recurrent urticaria is common in horses, yet our understanding is limited and focussed on IgE and T-helper 2 cell response. Prospective, controlled studies on treatments for urticaria are lacking. Glucocorticoids and antihistamines are primary reported treatments.
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Affiliation(s)
- R Marsella
- Department of Small Animal Clinical Sciences, College of Veterinary Medicine, University of Florida, Gainesville, Florida, USA
| | - S White
- Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis, California, USA
| | - V A Fadok
- Zoetis, US PET CARE, Bellaire, Texas, USA
| | - D Wilson
- School of Clinical Veterinary Sciences, University of Bristol, Bristol, UK
| | - R Mueller
- Medizinische Keleintierklinik, Zentrum für klinische Tiermedizin, LMU, Munich, Germany
| | - C Outerbridge
- Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis, California, USA
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Krager KL, Pigott AM. Retrospective review of diphenhydramine vs diphenhydramine plus glucocorticoid for the treatment of allergic reaction in cats. J Feline Med Surg 2023; 25:1098612X231173521. [PMID: 37278221 PMCID: PMC10811981 DOI: 10.1177/1098612x231173521] [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] [Indexed: 06/07/2023]
Abstract
OBJECTIVES The aims of the present study were to report the outcomes of treating allergic reactions in cats with diphenhydramine vs diphenhydramine plus glucocorticoid and to determine whether signs recurred or additional veterinary intervention was needed in the days after initial treatment. METHODS This retrospective study evaluated 73 cats treated for allergic reaction with diphenhydramine alone or in combination with a glucocorticoid at a 24 h emergency and specialty referral veterinary hospital between 1 January 2012 and 31 March 2021. RESULTS In total, 44 cats were treated with diphenhydramine alone, and 29 were treated with diphenhydramine plus dexamethasone sodium phosphate. The inciting cause was known or highly suspected in 50 patients. Vaccines were the most common (31 patients), followed by insect envenomation (17 cases). No cat in either group progressed to anaphylaxis. There was no difference in resolution of clinical signs between the groups. Follow-up contact was successfully made with 40/73 cat owners. All 40 cats were alive. Eight had persistent signs. There was no difference in the number of cats with persistent signs between groups. Five cats required additional treatment after the initial emergency visit. There was no difference between the two groups for persistent signs at follow-up. CONCLUSIONS AND RELEVANCE There was no difference in measured outcomes between cats treated with diphenhydramine alone vs those treated with a glucocorticoid in addition to diphenhydramine in this population. The ideal treatment for allergic reactions is unknown. Based on currently available data in human and veterinary literature, glucocorticoids are not indicated to treat acute allergic reactions. The role of antihistamines as part of a symptomatic supportive treatment plan to shorten the duration of signs is unclear at this time and may be considered.
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Affiliation(s)
- Kayla L Krager
- Emergency and Critical Care, BluePearl PVSEC North Hills, Pittsburgh, PA, USA
| | - Armi M Pigott
- Clinical Sciences, Cornell University College of Veterinary Medicine, Ithaca, NY, USA
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3
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White SD. Approach to the pruritic horse. J Am Vet Med Assoc 2023; 261:S66-S74. [PMID: 36638000 DOI: 10.2460/javma.22.10.0444] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2022] [Accepted: 12/05/2022] [Indexed: 01/14/2023]
Abstract
Pruritus in the horse may be due to several causes, the most common being a hypersensitivity response to salivary proteins in the Culicoides genera, which may coexist with atopic dermatitis, also known as an environmental allergy to pollens, molds, dust, storage mites, etc. Less common etiologies are food allergy and contact allergy, the latter often caused by owners applying various products to the skin. Other ectoparasites, such as Chorioptes mites, may also initiate pruritus. Secondary bacterial infections (usually Staphylococcus spp) may be pruritic in and of themselves. This article reviews the questions that need to be asked of owners to obtain a relevant history, always important for any organ system, but perhaps none more so than the skin. The various clinical findings such as alopecia and crusts and their location on the horse, diagnostic methods such as intradermal or serum testing for allergies, and subsequent hyposensitization are also discussed. Therapeutic options currently available for the potential underlying diseases, in particular for the hypersensitivity reactions to Culicoides spp or environmental allergens, are reviewed with the studies of hyposensitization over the last 40 years, as well as medications that may be effective. While the most common causes of pruritus in the horse are known, the current understanding of the pathophysiology still needs to be investigated, and consequently, the most effective treatments for those causes need to be improved. Newer research is discussed that may eventually add to the diagnostic and therapeutic options currently available for the pruritic horse.
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Affiliation(s)
- Stephen D. White
- School of Veterinary Medicine, University of California-Davis, Davis, CA
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Adamič N, Prpar Mihevc S, Blagus R, Kramarič P, Krapež U, Majdič G, Viel L, Hoffman AM, Bienzle D, Vengust M. Effect of intrabronchial administration of autologous adipose-derived mesenchymal stem cells on severe equine asthma. Stem Cell Res Ther 2022; 13:23. [PMID: 35063028 PMCID: PMC8777441 DOI: 10.1186/s13287-022-02704-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Accepted: 01/04/2022] [Indexed: 01/20/2023] Open
Abstract
BACKGROUND Severe equine asthma (SEA) is a common chronic respiratory disease and a significant health and well-being problem in horses. Current therapeutic strategies improve pulmonary function and clinical signs in some horses, but in the long-term, return to full athletic function appears to be rare. The aim of this study was to assess the safety and the effect of intrabronchial administration of adipose-derived mesenchymal stem cells (AD-MSC) on pulmonary inflammatory and clinical parameters in horses with SEA. METHODS This was a randomized controlled trial. Twenty adult horses diagnosed with SEA were randomly divided into two groups (n = 10), and treated either with a single intrabronchial application of autologous AD-MSC or oral dexamethasone for three weeks. A targeted clinical examination with determination of clinical score, maximal change in pleural pressure during the breathing cycle, and an endoscopic examination of the airways were performed at baseline and three weeks after treatment. Bronchoalveolar lavage fluid was analyzed cytologically, and IL-1β, IL-4, IL-8, IL-17, TNFα and IFNγ mRNA and protein concentrations were measured at baseline and three weeks. The horses were then monitored over one year for recurrence of SEA. A non-inferiority analysis and a linear mixed-effects model were performed to assess differences between treatments. RESULTS The non-inferiority of AD-MSC treatment was not established. However, AD-MSC administration significantly ameliorated the clinical score (P = 0.01), decreased the expression of IL-17 mRNA (P = 0.05) and IL-1β (P ≤ 0.001), IL-4 (P ≤ 0.001), TNFα (P = 0.02) protein levels, and had a positive long-term effect on SEA-associated clinical signs (P = 0.02). CONCLUSIONS Intrabronchial administration of AD-MSC had limited short-term anti-inflammatory effects but improved the clinical signs of SEA at one year.
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Affiliation(s)
- Neža Adamič
- Veterinary Faculty, University of Ljubljana, 1000, Ljubljana, Slovenia
| | | | - Rok Blagus
- Institute for Biostatistics and Medical Informatics, Faculty of Medicine, University of Ljubljana, 1000, Ljubljana, Slovenia
| | - Petra Kramarič
- Veterinary Faculty, University of Ljubljana, 1000, Ljubljana, Slovenia
| | - Uroš Krapež
- Veterinary Faculty, University of Ljubljana, 1000, Ljubljana, Slovenia
| | - Gregor Majdič
- Veterinary Faculty, University of Ljubljana, 1000, Ljubljana, Slovenia
| | - Laurent Viel
- Clinical Studies, University of Guelph, Guelph, ON, Canada
| | - Andrew M Hoffman
- School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Dorothee Bienzle
- Department of Pathobiology, University of Guelph, Guelph, ON, Canada
| | - Modest Vengust
- Veterinary Faculty, University of Ljubljana, 1000, Ljubljana, Slovenia.
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Mainguy-Seers S, Lavoie JP. Glucocorticoid treatment in horses with asthma: A narrative review. J Vet Intern Med 2021; 35:2045-2057. [PMID: 34085342 PMCID: PMC8295667 DOI: 10.1111/jvim.16189] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2021] [Revised: 05/13/2021] [Accepted: 05/18/2021] [Indexed: 12/15/2022] Open
Abstract
Despite substantial research efforts to improve the treatment and outcome of horses with asthma, glucocorticoids (GC) remain the cornerstone of drug treatment of this prevalent disease. The high efficacy of GC to relieve airway obstruction explains their extensive use despite potential deleterious effects. However, much is yet to be uncovered concerning GC use in horses with asthma, including the comparative efficacy of the different drugs, the determination of minimal effective doses and the mechanisms underlying their variable modulation of airway inflammation. The objectives of this structured review were to report and compare the plethora of effects of the various GC used in asthmatic horses with a focus on impact on lung function, airway inflammation, and bronchial remodeling. Adverse effects are also briefly described, with an emphasis on those that have been specifically reported in horses with asthma. Ultimately, we aimed to highlight gaps in the literature and to identify future research areas.
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Affiliation(s)
- Sophie Mainguy-Seers
- Faculty of Veterinary Medicine, Department of Clinical Sciences, Université de Montréal, St-Hyacinthe, Quebec, Canada
| | - Jean-Pierre Lavoie
- Faculty of Veterinary Medicine, Department of Clinical Sciences, Université de Montréal, St-Hyacinthe, Quebec, Canada
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de Wasseige S, Picotte K, Lavoie JP. Nebulized dexamethasone sodium phosphate in the treatment of horses with severe asthma. J Vet Intern Med 2021; 35:1604-1611. [PMID: 33817859 PMCID: PMC8162592 DOI: 10.1111/jvim.16113] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2020] [Revised: 03/10/2021] [Indexed: 02/06/2023] Open
Abstract
Background A study reported low systemic availability of injectable dexamethasone nebulized to healthy horses using the Flexineb mask. When used in horses with severe asthma and a different nebulizer, lack of efficacy and cortisol suppression were observed. Hypothesis Nebulized dexamethasone is as effective as PO administration for the treatment of severe asthma in horses. Animals Twelve horses with severe asthma from a research herd. Methods Randomized clinical trial. Horses were divided into 2 groups and received 5 mg of dexamethasone sodium phosphate by nebulization using a Flexineb mask (NE, n = 6) or PO (OR, n = 6) q24h for 7 days. Lung function and serum cortisol concentrations were evaluated at baseline, after 4 days of treatment (D4) and 1 day after the last treatment (D8). Data were analyzed using linear mixed models with Benjamini‐Hochberg adjustments. Results Lung resistance significantly improved at D4 (mean decrease ± SD, −1.5 ± 0.45 cm H₂O/L/s; 95% confidence interval [CI], −2; −0.6) and D8 (−1.4 ± 0.45 cm H₂O/L/s; 95% CI, −2.4; −0.5) compared to baseline in the OR group only (P = .004 and .01, respectively). Serum cortisol concentration was significantly decreased at D4 and D8 for both groups (maximum decrease, −1.2 ± 0.3 μg/dL; 95% CI, −1.9; −0.6 at D4 for NE group and −2.2 ± 0.3 μg/dL; 95% CI, −2.8; −1.6 at D8 for OR group; P < .001). Conclusions and Clinical Importance Oral, but not nebulized dexamethasone is an effective therapy for horses with severe asthma and both treatment modalities inhibit the hypothalamic‐pituitary‐adrenal axis.
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Affiliation(s)
- Selena de Wasseige
- Department of Clinical Sciences, Faculty of Veterinary Medicine, University of Montreal, Saint-Hyacinthe, Quebec, Canada
| | - Khristine Picotte
- Department of Clinical Sciences, Faculty of Veterinary Medicine, University of Montreal, Saint-Hyacinthe, Quebec, Canada
| | - Jean-Pierre Lavoie
- Department of Clinical Sciences, Faculty of Veterinary Medicine, University of Montreal, Saint-Hyacinthe, Quebec, Canada
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Pirie RS, Mueller HW, Engel O, Albrecht B, von Salis-Soglio M. Inhaled ciclesonide is efficacious and well tolerated in the treatment of severe equine asthma in a large prospective European clinical trial. Equine Vet J 2021; 53:1094-1104. [PMID: 33403727 PMCID: PMC8518630 DOI: 10.1111/evj.13419] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2020] [Revised: 10/22/2020] [Accepted: 12/17/2020] [Indexed: 01/15/2023]
Abstract
Background Ciclesonide is a glucocorticoid prodrug, already registered for human use. Due to its mode of action and inhaled route of administration, it was considered an appropriate treatment option for horses with severe equine asthma. Although the efficacy of inhaled ciclesonide has been demonstrated in horses with asthma exacerbations under controlled mouldy hay challenge conditions, it has not yet been reported under field conditions. Objectives To assess the effectiveness and safety of inhaled ciclesonide for the treatment of severe equine asthma. Study design Prospective, multicentre, placebo‐controlled, randomised, double‐blinded study. Methods Two‐hundred and twenty‐four client‐owned horses with severe equine asthma were randomised (1:1 ratio) to receive either ciclesonide inhalation (343 µg/actuation) solution or placebo (0 µg/actuation). Treatments (placebo or ciclesonide) were administered with a nonpressurised Soft Mist™ inhaler specifically developed for horses (Aservo® EquiHaler®) at doses of 8 actuations twice daily for the first 5 days and 12 actuations once daily for the following 5 days. Primary outcome was a success/failure analysis with the a priori definition of treatment success as a 30% or greater reduction in weighted clinical score (WCS) between Day 0 and Day 10 (±1). Results The treatment success rate (as defined above) in ciclesonide‐treated horses was 73.4% (80/109) after 10 (±1) days of treatment, being significantly higher than in the placebo group with 43.2% (48/111; P < 0.0001). Few systemic and local adverse events of ciclesonide were observed. Main limitations The severity of clinical signs of severe equine asthma varies over time; despite the prohibition of environmental management changes during the study, a placebo effect was also identified. This potentially contributed, in part, to the clinical improvement observed in the ciclesonide‐treated group. Conclusions Ciclesonide inhalation solution administered by the Aservo® EquiHaler® effectively reduced severity of clinical signs in a majority of horses with severe equine asthma and was well tolerated.
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Affiliation(s)
- Robert Scott Pirie
- Royal (Dick) School of Veterinary Studies, University of Edinburgh, Easter Bush Veterinary Centre, Roslin, UK
| | | | - Odilo Engel
- Boehringer Ingelheim Vetmedica GmbH, Ingelheim, Germany
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Symonds NE, Dart AJ, Keledjian J, Lau ML, Ennis LC, McIver VC, Tsang AS, Biasutti SA, Jeffcott LB. Pilot study to quantify the time to clear dexamethasone from plasma and urine of adult horses following a single nebulisation. Aust Vet J 2019; 97:144-148. [PMID: 31025330 DOI: 10.1111/avj.12800] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2018] [Revised: 01/09/2019] [Accepted: 02/21/2019] [Indexed: 11/28/2022]
Abstract
OBJECTIVE To quantify the time to clear dexamethasone from plasma and urine of horses following a single nebulisation. DESIGN Experimental using six Standardbred mares. METHODS Dexamethasone sodium phosphate (0.04 mg/kg) diluted in 0.9% sodium chloride was administered as an aerosol using a Flexineb E2® nebuliser. Blood samples (0, 2, 4, 6, 8, 10, 12, 24, 32, 48, 72 and 96 h) and urine samples (0, 1, 4, 8, 24, 32, 48, 72 and 96 h) were collected for analysis using liquid chromatography mass spectrometry. RESULTS Maximum plasma concentrations (tmax ) were reached by the earliest detection point (2 h) after nebulisation (0.6-1.8 ng/mL), but was no longer detectable at 48 h. However, in one horse 0.1 ng/mL was found at 96 h after three consecutive readings of 0 ng/mL. The tmax in urine was reached by the earliest collection point (1 h) after nebulisation (3.2-23.8 ng/mL), but was no longer present in urine at 72 h in five horses, while detectable levels (0.1 ng/mL) were still present at 96 h in one horse. CONCLUSIONS A single dose of 0.04 mg/kg of DSP administered as an aerosol through a FlexinebE2® mask was no longer detectable in blood at 48 h in six horses tested, but one horse returned a reading of 0.1 ng/mL at 96 h after having no detectable levels. Dexamethasone was not detectable in urine at 72 h in five horses but was detectable at a low concentration (0.1 ng/mL) at 96 h in one horse.
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Affiliation(s)
- N E Symonds
- Research and Clinical Trials Unit, University Veterinary Teaching Hospital Camden, University of Sydney, 410 Werombi Road, Camden, New South Wales, 2570, Australia
| | - A J Dart
- Research and Clinical Trials Unit, University Veterinary Teaching Hospital Camden, University of Sydney, 410 Werombi Road, Camden, New South Wales, 2570, Australia
| | - J Keledjian
- Australian Racing Forensic Laboratory - Racing NSW, Sydney, NSW, Australia
| | - M Liu Lau
- Australian Racing Forensic Laboratory - Racing NSW, Sydney, NSW, Australia
| | - L C Ennis
- Australian Racing Forensic Laboratory - Racing NSW, Sydney, NSW, Australia
| | - V C McIver
- Research and Clinical Trials Unit, University Veterinary Teaching Hospital Camden, University of Sydney, 410 Werombi Road, Camden, New South Wales, 2570, Australia
| | - A S Tsang
- Research and Clinical Trials Unit, University Veterinary Teaching Hospital Camden, University of Sydney, 410 Werombi Road, Camden, New South Wales, 2570, Australia
| | - S A Biasutti
- Research and Clinical Trials Unit, University Veterinary Teaching Hospital Camden, University of Sydney, 410 Werombi Road, Camden, New South Wales, 2570, Australia
| | - L B Jeffcott
- Research and Clinical Trials Unit, University Veterinary Teaching Hospital Camden, University of Sydney, 410 Werombi Road, Camden, New South Wales, 2570, Australia
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Lavoie JP, Bullone M, Rodrigues N, Germim P, Albrecht B, von Salis-Soglio M. Effect of different doses of inhaled ciclesonide on lung function, clinical signs related to airflow limitation and serum cortisol levels in horses with experimentally induced mild to severe airway obstruction. Equine Vet J 2019; 51:779-786. [PMID: 30854685 PMCID: PMC7379559 DOI: 10.1111/evj.13093] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2018] [Accepted: 03/02/2019] [Indexed: 12/20/2022]
Abstract
Background Inhaled corticosteroids are effective for the treatment of equine asthma but they induce cortisol suppression with potential side effects. Objectives To study the efficacy of ciclesonide, an inhaled corticosteroid with an improved safety profile, on lung function, clinical signs related to airway obstruction, and serum cortisol levels in asthmatic horses exposed to a mouldy hay challenge. Study design Cross‐over placebo controlled, blinded, randomised experiment. Methods Sixteen horses were enrolled in three subsequent dose‐titration studies (8 horses/study) to investigate the effects of inhaled ciclesonide administered for 2 weeks at doses ranging from 450 to 2700 μg twice daily or 3712.5 μg once daily. Systemic dexamethasone (0.066 mg/kg per os) was our positive control. A placebo group was also studied. Lung function and clinical scores were blindly performed before and after 7 and 14 days of treatment. Serum cortisol was measured before and after 3, 5, 7, 10, 14 days of treatment as well as 3 and 7 days post treatment. Results After 7 days, dexamethasone induced a significant reduction in pulmonary resistance (from 2.5 ± 0.6 at day 0 to 1.1 ± 0.7 cm H2O/L/s), pulmonary elastance (5.0 ± 2.6 to 1.2 ± 1.0 cm H2O/L), and of the weighted clinical score (14.8 ± 4.7 to 8.0 ± 4.4). Similarly, ciclesonide 1687.5 μg twice daily significantly improved pulmonary resistance (2.7 ± 1.1 to 1.6 ± 0.8 cm H2O/L/s), pulmonary elastance (5.2 ± 3.1 to 2.2 ± 1.3 cm H2O/L), and weighted clinical score (13 ± 2.9 to 10.8 ± 4.2). Serum cortisol suppression (<50 nmol/L) systematically occurred with dexamethasone from day 3 of treatment up to day 3 post treatment, but not with ciclesonide at any tested doses. Placebo did not exert any significant beneficial effect. Main limitations Experimentally induced asthma exacerbations in horses might respond differently to treatment than naturally occurring exacerbations. Conclusions Inhaled ciclesonide is an effective treatment for horses with equine asthma. Serum cortisol was unaffected by treatment.
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Affiliation(s)
- J-P Lavoie
- Department of Clinical Sciences, Université de Montréal, St-Hyacinthe, Quebec, Canada
| | - M Bullone
- Department of Clinical Sciences, Université de Montréal, St-Hyacinthe, Quebec, Canada
| | - N Rodrigues
- Department of Clinical Sciences, Université de Montréal, St-Hyacinthe, Quebec, Canada
| | - P Germim
- Department of Clinical Sciences, Université de Montréal, St-Hyacinthe, Quebec, Canada
| | - B Albrecht
- Boehringer Ingelheim Vetmedica GmbH, Ingelheim am Rhein, Germany
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Haspel AD, Giguère S, Hart KA, Berghaus LJ, Davis JL. Bioavailability and tolerability of nebulised dexamethasone sodium phosphate in adult horses. Equine Vet J 2017; 50:85-90. [PMID: 28719014 DOI: 10.1111/evj.12724] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2017] [Accepted: 07/11/2017] [Indexed: 12/21/2022]
Abstract
BACKGROUND Nebulisation of the injectable dexamethasone sodium phosphate (DSP) would offer an inexpensive way of delivering a potent corticosteroid directly to the lungs of horses with asthma. However, this approach would be advantageous only if systemic absorption is minimal and if the preservatives present in the formulation do not induce airway inflammation. OBJECTIVE To investigate the bioavailability of nebulised DSP and determine whether it induces airway inflammation or hypothalamic-pituitary-adrenal (HPA) axis suppression in healthy adult horses. STUDY DESIGN Randomised crossover experiment. METHODS Dexamethasone sodium phosphate was administered to six healthy adult horses at a dose of 5 mg q. 24 h for 5 days via nebulised, or intravenous (i.v.) routes. Plasma dexamethasone concentrations were measured by UPLC/MS-MS to calculate bioavailability. Cytological examination of bronchoalveolar fluid was performed at baseline and after the last dose of DSP. A validated chemiluminescent immunoassay was used to measure basal serum cortisol concentrations. RESULTS After nebulisation to adult horses, dexamethasone had a mean (±s.d.) maximum plasma concentration of 0.774 ± 0.215 ng/mL and systemic bioavailability of 4.3 ± 1.2%. Regardless of route of administration, there was a significant decrease in the percentage of neutrophils in bronchoalveolar lavage fluid over time. During i.v. administration, basal serum cortisol concentration decreased significantly from baseline to Day 3 and remained low on Day 5. In contrast, basal serum cortisol concentration did not change significantly during administration via nebulisation. MAIN LIMITATIONS Small sample size and short period of drug administration. CONCLUSIONS Dexamethasone sodium phosphate administered via nebulisation had minimal systemic bioavailability and did not induce lower airway inflammation or HPA axis suppression in healthy horses.
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Affiliation(s)
- A D Haspel
- Department of Large Animal Medicine, College of Veterinary Medicine, University of Georgia, Athens, Georgia, USA
| | - S Giguère
- Department of Large Animal Medicine, College of Veterinary Medicine, University of Georgia, Athens, Georgia, USA
| | - K A Hart
- Department of Large Animal Medicine, College of Veterinary Medicine, University of Georgia, Athens, Georgia, USA
| | - L J Berghaus
- Department of Large Animal Medicine, College of Veterinary Medicine, University of Georgia, Athens, Georgia, USA
| | - J L Davis
- Department of Biomedical Sciences and Pathobiology, VA-MD College of Veterinary Medicine, Blacksburg, Virginia, USA
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Leclere M. Corticosteroids and Immune Suppressive Therapies in Horses. Vet Clin North Am Equine Pract 2017; 33:17-27. [PMID: 28325178 DOI: 10.1016/j.cveq.2016.11.008] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Immune suppressive therapies target exaggerated and deleterious responses of the immune system. Triggered by exogenous or endogenous factors, these improper responses can lead to immune or inflammatory manifestations, such as urticaria, equine asthma, or autoimmune and immune-mediated diseases. Glucocorticoids are the most commonly used immune suppressive drugs and the only ones supported by robust evidence of clinical efficacy in equine medicine. In some conditions, combining glucocorticoids with other pharmacologic and nonpharmacologic treatments, such as azathioprine, antihistamine, bronchodilators, environmental management, or desensitization, can help to decrease dosages and associated side effects.
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Affiliation(s)
- Mathilde Leclere
- Department of Clinical Sciences, Faculty of Veterinary Medicine, Université de Montréal, 3200 Sicotte, St-Hyacinthe, Quebec J2S 7C6, Canada.
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Calzetta L, Roncada P, di Cave D, Bonizzi L, Urbani A, Pistocchini E, Rogliani P, Matera MG. Pharmacological treatments in asthma-affected horses: A pair-wise and network meta-analysis. Equine Vet J 2017; 49:710-717. [PMID: 28295526 DOI: 10.1111/evj.12680] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2016] [Accepted: 02/21/2017] [Indexed: 12/14/2022]
Abstract
BACKGROUND Equine asthma is a disease characterised by reversible airflow obstruction, bronchial hyper-responsiveness and airway inflammation following exposure of susceptible horses to specific airborne agents. Although clinical remission can be achieved in a low-airborne dust environment, repeated exacerbations may lead to irreversible airway remodelling. The available data on the pharmacotherapy of equine asthma result from several small studies, and no head-to-head clinical trials have been conducted among the available medications. OBJECTIVES To assess the impact of the pharmacological interventions in equine asthma and compare the effect of different classes of drugs on lung function. STUDY DESIGN Pair-wise and network meta-analysis. METHODS Literature searches for clinical trials on the pharmacotherapy of equine asthma were performed. The risk of publication bias was assessed by funnel plots and Egger's test. Changes in maximum transpulmonary or pleural pressure, pulmonary resistance and dynamic lung compliance vs. control were analysed via random-effects models and Bayesian networks. RESULTS The results obtained from 319 equine asthma-affected horses were extracted from 32 studies. Bronchodilators, corticosteroids and chromones improved maximum transpulmonary or pleural pressure (range: -8.0 to -21.4 cmH2 O; P<0.001). Bronchodilators, corticosteroids and furosemide reduced pulmonary resistance (range: -1.2 to -1.9 cmH2 O/L/s; P<0.001), and weakly increased dynamic lung compliance. Inhaled β2 -adrenoreceptor (β2 -AR) agonists and inhaled corticosteroids had the highest probability of being the best therapies. Long-term treatments were more effective than short-term treatments. MAIN LIMITATIONS Weak publication bias was detected. CONCLUSIONS This study demonstrates that long-term treatments with inhaled corticosteroids and long-acting β2 -AR agonists may represent the first choice for treating equine asthma. Further high quality clinical trials are needed to clarify whether inhaled bronchodilators should be preferred to inhaled corticosteroids or vice versa, and to investigate the potential superiority of combination therapy in equine asthma.
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Affiliation(s)
- L Calzetta
- Department of Systems Medicine, University of Rome Tor Vergata, Rome, Italy
| | - P Roncada
- Istituto Sperimentale Italiano Lazzaro Spallanzani, Milan, Italy
| | - D di Cave
- Dipartimento di Scienze Cliniche e Medicina Traslazionale, University of Rome Tor Vergata, Rome, Italy
| | - L Bonizzi
- Dipartimento di Medicina Veterinaria, University of Milan, Milan, Italy
| | - A Urbani
- Istituto di Biochimica e Biochimica Clinica, Università Cattolica, Milan, Italy
| | | | - P Rogliani
- Department of Systems Medicine, University of Rome Tor Vergata, Rome, Italy
| | - M G Matera
- Department of Experimental Medicine, University of Campania Luigi Vanvitelli, Naples, Italy
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Mora Pereira M, Groover E, Wooldridge A, Caldwell F. Review of glucocorticoid therapy in horses. Part 2: Clinical use of systemic glucocorticoids in horses. EQUINE VET EDUC 2016. [DOI: 10.1111/eve.12624] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- M. Mora Pereira
- J. T. Vaughan Large Animal Teaching Hospital; Auburn University; Alabama USA
| | - E. Groover
- J. T. Vaughan Large Animal Teaching Hospital; Auburn University; Alabama USA
| | - A. Wooldridge
- J. T. Vaughan Large Animal Teaching Hospital; Auburn University; Alabama USA
| | - F. Caldwell
- J. T. Vaughan Large Animal Teaching Hospital; Auburn University; Alabama USA
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14
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Ivester KM, Couëtil LL. Management of chronic airway inflammation in the horse: A systematic review. EQUINE VET EDUC 2014. [DOI: 10.1111/eve.12238] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- K. M. Ivester
- College of Veterinary Medicine; Veterinary Clinical Sciences; Purdue University; West Lafayette Indiana USA
| | - L. L. Couëtil
- College of Veterinary Medicine; Veterinary Clinical Sciences; Purdue University; West Lafayette Indiana USA
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15
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Pirie RS. Recurrent airway obstruction: a review. Equine Vet J 2014; 46:276-88. [PMID: 24164473 DOI: 10.1111/evj.12204] [Citation(s) in RCA: 83] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2013] [Accepted: 10/05/2013] [Indexed: 12/01/2022]
Abstract
Recurrent airway obstruction is a widely recognised airway disorder, characterised by hypersensitivity-mediated neutrophilic airway inflammation and lower airway obstruction in a subpopulation of horses when exposed to suboptimal environments high in airborne organic dust. Over the past decade, numerous studies have further advanced our understanding of different aspects of the disease. These include clarification of the important inhaled airborne agents responsible for disease induction, improving our understanding of the underlying genetic basis of disease susceptibility and unveiling the fundamental immunological mechanisms leading to establishment of the classic disease phenotype. This review, as well as giving a clinical overview of recurrent airway obstruction, summarises much of the work in these areas that have culminated in a more thorough understanding of this debilitating disease.
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Affiliation(s)
- R S Pirie
- Royal (Dick) School of Veterinary Studies and Roslin Institute, University of Edinburgh, Roslin, Midlothian, UK
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16
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SOMA LR, UBOH CE, LIU Y, LI X, ROBINSON MA, BOSTON RC, COLAHAN PT. Pharmacokinetics of dexamethasone following intra-articular, intravenous, intramuscular, and oral administration in horses and its effects on endogenous hydrocortisone. J Vet Pharmacol Ther 2012; 36:181-91. [DOI: 10.1111/j.1365-2885.2012.01412.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Abstract
Animal models have been developed to investigate specific components of asthmatic airway inflammation, hyper-responsiveness or remodelling. However, all of these aspects are rarely observed in the same animal. Heaves is a naturally occurring disease of horses that combines these features. It is characterized by stable dust-induced inflammation, bronchospasm and remodelling. The evaluation of horses during well-controlled natural antigen exposure and avoidance in experimental settings allows the study of disease mechanisms in the asymptomatic and symptomatic stages, an approach rarely feasible in humans. Also, the disease can be followed over several years to observe the cumulative effect of repeated episodes of clinical exacerbation or to evaluate long-term treatment, contrasting most murine asthma models. This model has shown complex gene and environment interactions, the involvement of both innate and adaptive responses to inflammation, and the contribution of bronchospasm and tissue remodelling to airway obstruction, all occurring in a natural setting. Similarities with the human asthmatic airways are well described and the model is currently being used to evaluate airway remodelling and its reversibility in ways that are not possible in people for ethical reasons. Tools including antibodies, recombinant proteins or gene arrays, as well as methods for sampling tissues and assessing lung function in the horse are constantly evolving to facilitate the study of this animal model. Research perspectives that can be relevant to asthma include the role of neutrophils in airway inflammation and their response to corticosteroids, systemic response to pulmonary inflammation, and maintaining athletic capacities with early intervention.
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Affiliation(s)
- Mathilde Leclere
- Department of Clinical Sciences, Faculty of Veterinary Medicine, Université de Montréal, St-Hyacinthe, Canada
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Gerber V, Schott Ii HC, Robinson NE. Owner assessment in judging the efficacy of airway disease treatment. Equine Vet J 2011; 43:153-8. [PMID: 21592208 DOI: 10.1111/j.2042-3306.2010.00156.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
REASONS FOR PERFORMING STUDY Efficacy of medications for recurrent airway obstruction is typically tested using clinical, cytological and lung function examinations of severely affected animals. These trials are technically challenging and may not adequately reflect the spectrum of disease and owner complaints encountered in clinical practice. OBJECTIVE To determine if owners of horses with chronic airway disease are better able to detect drug efficacy than a veterinarian who clinically examines horses infrequently. METHOD In a double-blinded randomised controlled trial, owners and a veterinarian compared the efficacy of dexamethasone (0.1 mg/kg bwt per os, q. 24 h, for 3 weeks; n = 9) to placebo (n = 8) in horses with chronic airway disease. Before and after treatment, owners scored performance, breathing effort, coughing and nasal discharge using a visual analogue scale (VAS). The clinician recorded vital parameters, respiratory distress, auscultation findings, cough and nasal discharge, airway mucus score, bronchoalveolar lavage fluid (BALF) cytology and arterial blood gases. RESULTS The VAS score improved significantly in dexamethasone- but not placebo-treated horses. In contrast, the clinician failed to differentiate between dexamethasone- and placebo-treated animals based on clinical observations, BALF cytology or endoscopic mucus score. Respiratory rate (RR) and arterial oxygen pressure (PaO(2)) improved with dexamethasone but not placebo. CONCLUSIONS AND CLINICAL RELEVANCE In the design of clinical trials of airway disease treatments, more emphasis should be placed on owner-assessed VAS than on clinical, cytological and endoscopic observations made during brief examinations by a veterinarian. Quantifiable indicators reflecting lung function such as RR and PaO(2) provide a good assessment of drug efficacy.
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Affiliation(s)
- V Gerber
- Department of Large Animal Clinical Sciences, Michigan State University, USA
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Leclere M, Lefebvre-Lavoie J, Beauchamp G, Lavoie JP. Efficacy of oral prednisolone and dexamethasone in horses with recurrent airway obstruction in the presence of continuous antigen exposure. Equine Vet J 2010; 42:316-21. [PMID: 20525049 DOI: 10.1111/j.2042-3306.2009.00022.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
REASONS FOR PERFORMING STUDY Orally administered prednisolone and dexamethasone are used commonly in the treatment of recurrent airway obstruction (RAO) in horses. However, the efficacy of prednisolone in improving pulmonary function during continuous antigen exposure has not been evaluated critically and there is little evidence supporting the efficacy of low-dose oral dexamethasone in the same conditions. HYPOTHESIS Oral prednisolone and dexamethasone improve pulmonary function in RAO under conditions of continuous antigen exposure, and dexamethasone is more effective than prednisolone at commonly used dosages. METHODS Using a randomised crossover design, prednisolone (2 mg/kg bwt) and dexamethasone (0.05 mg/kg bwt) were administered per os, s.i.d. for 7 days, to 7 horses during clinical exacerbation of the disease. Maximal difference in transpulmonary pressure (DeltaP(L)), lung resistance (R(L)) and elastance (E(L)) were measured before and after 3 and 7 days of treatment. RESULTS Prednisolone and dexamethasone improved pulmonary function significantly. However, the improvement was of greater magnitude after 3 and 7 days of treatment with dexamethasone compared to prednisolone. Also, after 7 days of treatment with dexamethasone, DeltaP(L) and R(L) were not different from values obtained when horses were on pasture, while all 3 pulmonary function parameters remained different from pasture values after prednisolone treatment. CONCLUSIONS Both corticosteroids improve pulmonary function, in spite of continuous antigen exposure. However, oral dexamethasone at 0.05 mg/kg bwt is more effective than prednisolone at 2 mg/kg bwt in the treatment of RAO. POTENTIAL RELEVANCE Prednisolone was shown, for the first time, to our knowledge, to improve the pulmonary function of horses with RAO in the presence of continuous antigen exposure. This study also demonstrates the efficacy of low-dose oral dexamethasone in reversing airway obstruction in these conditions.
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Affiliation(s)
- M Leclere
- Clinical Sciences Department, Faculté de Médecine Vétérinaire, Université de Montréal. 3200 Sicotte Saint-Hyacinthe, J2S 7C6, Quebec, Canada
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Robinson NE, Berney C, Behan A, Derksen FJ. Fluticasone propionate aerosol is more effective for prevention than treatment of recurrent airway obstruction. J Vet Intern Med 2009; 23:1247-53. [PMID: 19747193 DOI: 10.1111/j.1939-1676.2009.0382.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
BACKGROUND Efficacy of inhaled fluticasone propionate (FP) for management of recurrent airway obstruction (RAO) has only been evaluated after several weeks' treatment. OBJECTIVES To compare efficacy of (1) 3-day treatments with FP to dexamethasone (DEX) for management of RAO; and (2) FP and DEX to no treatment in prevention of acute RAO exacerbations. ANIMALS Nine RAO affected horses. METHODS Crossover studies in RAO-affected horses compared (a) 3-day treatment of RAO exacerbation with FP (3 and 6 mg q12h) and DEX (0.1 mg/kg q24h) and (b) FP (6 mg q12h) and DEX (0.1 mg/kg q24h) to no treatment for prevention of acute exacerbations of RAO. Treatment efficacy and unwanted effects were judged from maximal change in pleural pressure (DeltaPpl(max)), serum cortisol (COR), bronchoalveolar lavage (BAL) cytology, and subjective scores for respiratory distress and lameness. RESULTS In treatment trial, DEX and FP (6 mg) significantly decreased DeltaPpl(max) by 48 and 72 hours, respectively; FP (3 mg) had no significant effect. DEX decreased COR more than did FP. In prevention trial, both DEX and FP (6 mg) prevented the increase in DeltaPpl(max) that occurred in untreated horses. Both treatments decreased COR to the same degree. FP and DEX had no effects on bronchoalveolar lavage fluid (BALF) cytology and there was no evidence of laminitis. CONCLUSIONS AND CLINICAL IMPORTANCE FP (6 mg q12h) is as effective as DEX for prevention of acute exacerbations of RAO and lower doses should be evaluated. High-dose FP is not as effective as DEX for treatment of RAO exacerbations.
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Affiliation(s)
- N E Robinson
- Equine Pulmonary Laboratory, Department of Large Animal Clinical Sciences, Michigan State University, East Lansing, MI 48824, USA.
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Lecoq L, Vincent P, Lavoie-Lamoureux A, Lavoie JP. Genomic and non-genomic effects of dexamethasone on equine peripheral blood neutrophils. Vet Immunol Immunopathol 2008; 128:126-31. [PMID: 19036458 DOI: 10.1016/j.vetimm.2008.10.303] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
BACKGROUND Glucocorticoids have potent anti-inflammatory properties and are frequently used for the treatment of domestic animal species, including horses. They induce a down-regulation of multiple inflammatory pathways through both genomic and non-genomic effects. Currently, little is known on the effects of glucocorticoids on equine peripheral blood neutrophils. HYPOTHESIS Dexamethasone (DEX), a potent synthetic glucocorticoid, inhibits the functions of equine peripheral blood neutrophils through both genomic and non-genomic effects. ANIMALS Six healthy adult mixed breed female horses. METHODS To assess the genomic effects of DEX, peripheral blood neutrophils were isolated using a gradient technique and incubated 6 h with 100 ng/ml LPS and 10(-6) M DEX alone, or combined with the glucocorticoid receptor (GR) inhibitor RU486 (10(-5) M). Messenger RNA for IL-8, TNF-alpha and TLR-4 were measured using real-time RT-PCR. The non-genomic effects of DEX were studied in neutrophils incubated with 5 microM dichlorodihydrofluorescein (DCF) and 10(-6) M DEX 5, 10 and 15 min prior to being stimulated with 5 ng/ml phorbol myristate acetate. Neutrophils were similarly co-incubated with DEX (10(-6) M, 15 min) and RU486 (10(-5) M) to evaluate the contribution of the GR to these effects. The oxidation of DCF was studied using flow-cytometry. RESULTS Neutrophils stimulation with LPS resulted in a significant increase in IL-8, TNF-alpha and TLR-4 mRNA expressions (p<0.0001); incubation with DEX significantly down-regulated this process (p<0.0001). DEX significantly reduced oxidation of DCF after 10 and 15 min of incubation (p<0.0001). Those effects were mediated through the GRs. CONCLUSION DEX exerts anti-inflammatory effects on equine peripheral blood neutrophils through both genomic and non-genomic pathways.
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Affiliation(s)
- L Lecoq
- Department of Clinical Sciences, Faculty of Veterinary Medicine, Université de Montréal, 3200 Sicotte, Saint-Hyacinthe, Québec, Canada J2S 7C6
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Abstract
It is clear from a review of the current scientific literature that an evidence-based approach to medical treatment of equine respiratory disease can be applied, at least in the instance of common lower respiratory diseases. In particular, there is clear evidence for efficacious treatments for recurrent airway obstruction and exercise-induced pulmonary hemorrhage, and with the recognition of this evidence, these treatments should be the first to be considered by a practitioner when treating these conditions. The purpose of this article is not only to identify the existence of relevant high-quality studies for incorporation into an evidence-based veterinary medicine approach to patient care, but to highlight the features of those studies that should be considered when evaluating their value in individual situations.
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Affiliation(s)
- Katherine K Williamson
- Department of Physiological Sciences, Oklahoma State University Center for Veterinary Health Sciences, Stillwater, OK 74078, USA
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Cesarini C, Hamilton E, Picandet V, Lavoie JP. Theophylline does not potentiate the effects of a low dose of dexamethasone in horses with recurrent airway obstruction. Equine Vet J 2006; 38:570-3. [PMID: 17124849 DOI: 10.2746/042516407x153048] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
REASONS FOR PERFORMING STUDY Theophylline has been shown to have corticosteroid-sparing effects for the treatment of human asthma. A similar effect, if present in horses, would allow diminishing the dose of corticosteroids administered to equine patients with inflammatory airway diseases. OBJECTIVES To evaluate whether theophylline potentiates the effects of a low dose of dexamethasone when treating horses with recurrent airway obstruction (RAO). HYPOTHESIS Theophylline has steroid-sparing effects in horses with RAO. METHODS Ten mature mixed breed horses in clinical exacerbation of RAO were studied. Using an incomplete crossover design and 3 experimental periods of 7 days duration, horses were distributed randomly in 5 treatment groups; and administered dexamethasone s.i.d., at either 0.05 mg/kg bwt i.v. or per os, or 0.02 mg/kg bwt alone or combined with theophylline at 5 mg/kg bwt per os b.i.d. A fifth group was treated with theophylline alone at the above dosage. Lung function was evaluated prior to drug administration and then 3 and 7 days later. RESULTS Oral administration of dexamethasone alone or combined with theophylline failed to improve lung function significantly in RAO affected horses. Theophylline alone also failed to improve lung function in all treated horses. Conversely, dexamethasone administration at 0.05 mg/kg bwt i.v. resulted in a significant improvement in lung function starting on Day 3. CONCLUSIONS AND POTENTIAL RELEVANCE Oral theophylline for 7 days did not improve the effects of a low dose of dexamethasone for the treatment of horses with RAO.
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Affiliation(s)
- C Cesarini
- Département des Sciences Cliniques, Faculté de Médecine Vétérinaire, Université de Montréal, CP 5000, Saint-Hyacinthe, Québec J2S7C6, Canada
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