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Amini P, Okeme JO. Tear Fluid as a Matrix for Biomonitoring Environmental and Chemical Exposures. Curr Environ Health Rep 2024:10.1007/s40572-024-00454-7. [PMID: 38967858 DOI: 10.1007/s40572-024-00454-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/10/2024] [Indexed: 07/06/2024]
Abstract
PURPOSE Exposures to hazardous chemicals have been linked to many detrimental health effects and it is therefore critical to have effective biomonitoring methods to better evaluate key environmental exposures that increase the risk of chronic disease and death. Traditional biomonitoring utilizing blood and urine is limited due to the specialized skills and invasiveness of collecting these fluid samples. This systematic review focuses on tear fluid, which is largely under-researched, as a promising complementary matrix to the traditional fluids used for biomonitoring. The objective is to evaluate the practicability of using human tear fluid for biomonitoring environmental exposures, highlighting potential pitfalls and opportunities. RECENT FINDING Tear fluid biomonitoring represents a promising method for assessing exposures because it can be collected with minimal invasiveness and tears contain exposure markers from both the external and internal environments. Tear fluid uniquely interfaces with the external environment at the air-tear interface, providing a surface for airborne chemicals to diffuse into the ocular environment and interact with biomolecules. Tear fluid also contains molecules from the internal environment that have travelled from the blood to tears by crossing the blood-tear barrier. This review demonstrates that tear fluid can be used to identify hazardous chemicals from the external environment and differentiate exposure groups.
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Affiliation(s)
- Parshawn Amini
- Department of Chemistry & Chemical Biology, McMaster University, Hamilton, ON, Ontario, L8S 4L8, Canada
| | - Joseph O Okeme
- Department of Chemistry & Chemical Biology, McMaster University, Hamilton, ON, Ontario, L8S 4L8, Canada.
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Goss R, Adams VJ, Heinrich C, Grundon R, Linn-Pearl R, Scurrell E, Hamzianpour N. Progressive ulcerative keratitis in dogs in the United Kingdom: Microbial isolates, antimicrobial sensitivity, and resistance patterns. Vet Ophthalmol 2024; 27:330-346. [PMID: 37933885 DOI: 10.1111/vop.13160] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2023] [Revised: 10/17/2023] [Accepted: 10/24/2023] [Indexed: 11/08/2023]
Abstract
OBJECTIVES The objective of the study was to identify bacterial pathogens and their antimicrobial sensitivity profile associated with cases of canine progressive ulcerative keratitis. MATERIALS AND METHODS Analysis of microbial culture and sensitivity results from dogs with progressive ulcerative keratitis presenting to a UK referral practice between December 2018 and August 2020. RESULTS Positive bacterial cultures were obtained from 80/148 (54%) of the canine ulcers sampled with 99 bacterial isolates cultured. Streptococcus canis (n = 29), Pseudomonas aeruginosa (n = 19), and Staphylococcus pseudintermedius (n = 16) were the most common isolates. Pseudomonas aeruginosa was more likely to be isolated whether the ulcer was clinically malacic at the time of sampling (OR = 10.1, p < .001). Ulcers treated prior to culture with fusidic acid were 7.6 times more likely to be positive than those treated with any other antimicrobial(s). Bacterial isolates demonstrated resistance against neomycin (85%), fusidic acid (78%), and tetracycline (68%). Conversely, isolates were most likely to be sensitive to gentamicin (88%), ofloxacin (77%), ciprofloxacin (73%), and chloramphenicol (64%). Antimicrobial combinations of chloramphenicol or gentamicin with a fluoroquinolone (ofloxacin or ciprofloxacin) or chloramphenicol combined with gentamicin were the most effective on in vitro analysis (over 90% susceptibility of all isolates). CONCLUSION The most common bacterial species associated with canine progressive ulcerative keratitis in a UK referral population were S. canis, P. aeruginosa, and S. pseudintermedius. Combination antimicrobial therapy is recommended pending culture and sensitivity results given the varied antimicrobial susceptibility profiles and significant bacterial in vitro resistance to antimicrobial monotherapy.
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Hung JH, Ford MM, Sanders MT, Stanley RG. Surgical management of unilateral restrictive strabismus in an 8-month-old dog. N Z Vet J 2024:1-7. [PMID: 38885962 DOI: 10.1080/00480169.2024.2361619] [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: 11/27/2023] [Accepted: 05/23/2024] [Indexed: 06/20/2024]
Abstract
CASE HISTORY An 8-month-old male, entire, mixed-breed dog was presented with a 1-month history of left exophthalmos and green mucopurulent ocular discharge. Subsequently, exophthalmos resolved but esotropia (medial strabismus) developed in the left eye, prompting referral to an ophthalmologist. CLINICAL FINDINGS At the initial referral consultation, enophthalmos and esotropia of the left eye were identified. The patient showed mild improvement after a 3-week tapering course of oral prednisolone and doxycycline. MRI was performed and showed left medial rectus muscle atrophy with increased contrast enhancement which was consistent with chronic extraocular muscle myositis (EOM). A forced duction test was performed to confirm the diagnosis of fibrosing esotropia, which is likely a sequela of chronic EOM. DIAGNOSIS Fibrosing esotropia presumably caused by untreated EOM. TREATMENT AND OUTCOME One month later, esotropia progressed to a marked ventro-medial strabismus resulting in visual deprivation. Surgical release of the ventral oblique, medial and ventral recti muscles was performed, resulting in immediate resolution of the enophthalmos. Despite a tapering post-operative course of oral prednisolone, mild esotropia was present 4 weeks later. In an effort to stabilise the globe position, the low dose of prednisolone was increased to a higher anti-inflammatory dose before slowly tapering over 2 months. The vision in the left eye was improved after surgery and has been maintained since without further treatment. CLINICAL RELEVANCE This is the first documented case of fibrosing esotropia in a young dog with prior signs of acute exophthalmos. Fibrosing esotropia has been documented in certain breeds or as a sequela to chronic EOM. In this patient, it was presumably caused by EOM, which was strongly supported by the case history, progression and MRI findings. Most historical reports of EOM described it as a bilateral condition that resolves with systemic corticosteroids at an anti-inflammatory dose. EOM has been shown to also present unilaterally and it can progress to strabismus if not promptly recognised and treated with systemic steroids. Surgical management can restore vision when severe strabismus results in visual deprivation.
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Affiliation(s)
- J H Hung
- Animal Eye Care, Melbourne, Australia
| | - M M Ford
- Animal Eye Care, Melbourne, Australia
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Dulaurent T, Rozoy M, Steun L, Isard PF. Multidirectional corneoconjunctival transposition in the treatment of large keratomalacia in 7 dogs and 5 cats. Vet Ophthalmol 2023. [PMID: 36943897 DOI: 10.1111/vop.13086] [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: 11/23/2022] [Revised: 02/14/2023] [Accepted: 03/02/2023] [Indexed: 03/23/2023]
Abstract
OBJECTIVE To describe the use of multidirectional corneoconjunctival transposition (CCT) as a surgical treatment for large keratomalacia. METHOD A prospective study including dogs and cats initially presenting with keratomalacia larger than 6 × 6 mm and affecting more than half of the corneal thickness. Signalment, concurrent eye diseases, ulcer size, bacterial culture and susceptibility testing results, follow-up, and outcome were recorded. The surgery consisted of harvesting of two or three opposite corneoconjunctival grafts, after removal of the malacic tissue using a square-edge keratectomy. The medical treatment consisted of administration of topical and systemic antibiotics, topical atropine, and N-acetylcysteine. Follow-up examinations were performed at D7, D14, D21, and D28, and then at various time points. The corneal clarity score (CCS) was recorded upon completion of the follow-up period. RESULTS Seven dogs and five cats were included. Brachycephalic dogs were overrepresented, with no breed predisposition in cats. Concurrent eye diseases were corneal pigmentation in three dogs, hypopyon in two dogs, nictitating membrane wound in one dog, and corneal perforation in one cat. The size of the keratomalacia ranged from 6 × 6 to 9.5 × 11.5 mm. The short-term complications were suture dehiscence (two of 12) and progression of the keratomalacia (one of 12). The long-term complications were corneal pigmentation (10 of 12), corneal epithelial inclusion cyst (two of 12), and marginal synechiae (one of 12). All animals were sighted at the last follow-up. The median CCS was G3 (range G2-G4). CONCLUSION Multidirectional CCT is an effective surgical treatment for large keratomalacia in dogs and cats.
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Affiliation(s)
- Thomas Dulaurent
- Centre Hospitalier Vétérinaire Saint-Martin, Allonzier-la-Caille, France
| | - Manon Rozoy
- Universitatea de Stiinte Agricole si Medicina Veterinara, Cluj-Napoca, Romania
| | - Laure Steun
- Centre Hospitalier Vétérinaire Saint-Martin, Allonzier-la-Caille, France
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Armstrong SK, Blacklock B, Keen J, Peck FS. Successful management of a unilateral persistent epithelial defect secondary to meibomian gland dysfunction in an Irish Sports Horse using a multi‐modal treatment plan. VETERINARY RECORD CASE REPORTS 2022. [DOI: 10.1002/vrc2.496] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Susan K. Armstrong
- The Royal (Dick) School of Veterinary Studies and the Roslin Institute University of Edinburgh Edinburgh UK
| | - Ben Blacklock
- The Royal (Dick) School of Veterinary Studies and the Roslin Institute University of Edinburgh Edinburgh UK
| | - John Keen
- The Royal (Dick) School of Veterinary Studies and the Roslin Institute University of Edinburgh Edinburgh UK
| | - Fraser S. Peck
- Ophthalmology Kent, Surrey, and Sussex Health Education London UK
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Bowden AC, Allbaugh RA, Smith JS, Mochel JP, Sebbag L. Kinetics and minimal inhibitory concentrations of ceftiofur in tear film following extended-release parenteral administration (Excede®) in dogs. Front Vet Sci 2022; 9:975113. [PMID: 36213401 PMCID: PMC9535610 DOI: 10.3389/fvets.2022.975113] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2022] [Accepted: 08/22/2022] [Indexed: 12/05/2022] Open
Abstract
Purpose Describe the pharmacokinetics of extended-release parenteral ceftiofur (Excede®) in canine tear film and compare these concentrations to minimal inhibitory concentrations (MICs) of ceftiofur against common ocular pathogens in dogs. Method Six dogs of various breeds were enrolled. Disruption of blood-tear barrier was achieved with histamine-induced conjunctivitis to ensure clinical relevance of the results. Each dog received a single subcutaneous injection of 5 mg/kg Excede®, followed by tear collection with Schirmer strips at times 0, 0.25, 0.5, 1, 2, 4, 8, 12, 24, 36, 48, 72, 96, 120, 144, 168, 192, 216 and 240 h. Drug quantification was performed with liquid chromatography-mass spectrometry. MICs were determined for Staphylococcus pseudintermedius, Streptococcus canis and Pseudomonas aeruginosa by assessing bacterial growth (n = 10 per bacterial species) in the presence of ceftiofur at increasing concentrations. Results Blood-tear barrier breakdown provided tear film concentrations of ceftiofur 3.2–28.9-fold higher than in the contralateral healthy eye (n = 1 dog, pilot experiment). In all six dogs, ceftiofur concentrations in tears varied from 2.3 to 637.5 ng/mL and were detectable up to 10 days (240 h) after subcutaneous injection. However, tear levels always remained below MICs for common ocular isolates (≥640 ng/mL). Conclusions Ceftiofur reached the tear compartment (for up to 10 days) after a single parenteral injection, however tear concentrations were extremely variable and too low to be effective against common bacterial pathogens in dogs. Further studies with different ceftiofur dosage or other long-acting injectable antibiotics are warranted.
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Affiliation(s)
- Anna Catherine Bowden
- Department of Veterinary Clinical Sciences, College of Veterinary Medicine, Iowa State University, Ames, IA, United States
| | - Rachel A. Allbaugh
- Department of Veterinary Clinical Sciences, College of Veterinary Medicine, Iowa State University, Ames, IA, United States
| | - Joe S. Smith
- Department of Biomedical Sciences, SMART Pharmacology, College of Veterinary Medicine, Iowa State University, Ames, IA, United States
| | - Jonathan P. Mochel
- Department of Biomedical Sciences, SMART Pharmacology, College of Veterinary Medicine, Iowa State University, Ames, IA, United States
| | - Lionel Sebbag
- Department of Veterinary Clinical Sciences, College of Veterinary Medicine, Iowa State University, Ames, IA, United States
- Department of Biomedical Sciences, SMART Pharmacology, College of Veterinary Medicine, Iowa State University, Ames, IA, United States
- Koret School of Veterinary Medicine, Hebrew University of Jerusalem, Rehovot, Israel
- *Correspondence: Lionel Sebbag
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Mileva R, Milanova A. Doxycycline pharmacokinetics in mammalian species of veterinary interest – an overview. BULGARIAN JOURNAL OF VETERINARY MEDICINE 2022. [DOI: 10.15547/bjvm.2321] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Doxycycline is a broad-spectrum tetracycline antibiotic widely used in veterinary medicine. The current review aims to summarise the available data about pharmacokinetics in mammalian species of veterinary interest and to indicate the basic strategies for refining dosage regimens in order to use this antibiotic reasonably. Additionally, the available data about population pharmacokinetics are reviewed as this approach exhibits a number of benefits in terms of determination of drug pharmacokinetics, prediction of drug disposition and interpretation of the variations in the pharmacokinetic parameters. Further research with animal species of veterinary interest and pathogens causing diseases in animals is needed to clarify the pharmacokinetics and pharmacodynamics of doxycycline.
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Affiliation(s)
- R. Mileva
- Department of Pharmacology, Animal Physiology and Physiological Chemistry, Facul-ty of Veterinary Medicine, Trakia University, 6000 Stara Zagora, Bulgaria
| | - A. Milanova
- Department of Pharmacology, Animal Physiology and Physiological Chemistry, Facul-ty of Veterinary Medicine, Trakia University, 6000 Stara Zagora, Bulgaria
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Tsvetanova A, Powell RM, Tsvetanov KA, Smith KM, Gould DJ. Melting corneal ulcers (keratomalacia) in dogs: A 5-year clinical and microbiological study (2014-2018). Vet Ophthalmol 2021; 24:265-278. [PMID: 33794048 DOI: 10.1111/vop.12885] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2020] [Revised: 03/15/2021] [Accepted: 03/15/2021] [Indexed: 01/26/2023]
Abstract
OBJECTIVES To identify bacterial microorganisms associated with canine keratomalacia, review their antimicrobial sensitivity, and evaluate clinical outcomes compared to results of microbial culture. METHODS Retrospective analysis of clinical records of dogs diagnosed with a melting corneal ulcer presented to a referral hospital in Hertfordshire, UK between 2014 and 2018. RESULTS One hundred and ten melting corneal ulcers were sampled in 106 dogs. The most common pure bacterial isolate was Pseudomonas aeruginosa (n = 26) followed by β-hemolytic Streptococcus (n = 12). Melting corneal ulcers that cultured coagulase-positive Staphylococcus, coliform bacteria, Pasteurella multocida, Enterococcus, and Streptococcus viridans presented in smaller numbers and were analyzed together (n = 16). Multiple cultures were identified in nine cases (n = 9). Forty-seven cultures yielded no bacterial growth (n = 47). The susceptibility to fluoroquinolones remained high with the exception of β-hemolytic Streptococci. There was no significant difference in the ulcer severity at presentation in regard to the cultured bacteria. Overall, 63 eyes (57%) received surgical grafting in addition to medical treatment. In 14 cases (13%), the progression of corneal melting despite medical ± surgical treatment resulted in enucleation. Fifty-seven percent (8/14) of the enucleated eyes cultured pure Pseudomonas aeruginosa isolates. In contrast, all β-hemolytic Streptococcus-associated ulcers healed. CONCLUSIONS The most common bacterial species associated with canine keratomalacia were Pseudomonas aeruginosa and β-hemolytic Streptococcus. Because of the variation in antibacterial sensitivity between these two species, bacterial culture and sensitivity testing should be performed in all dogs presenting with keratomalacia. Melting corneal ulcers associated with pure Pseudomonas infection were significantly more likely to result in globe loss than melting corneal ulcers associated with other cultures.
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Affiliation(s)
- Agata Tsvetanova
- Davies Veterinary Specialists, Manor Farm Business Park, Hertfordshire, UK
| | | | - Kamen A Tsvetanov
- Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK
| | - Kerry M Smith
- Davies Veterinary Specialists, Manor Farm Business Park, Hertfordshire, UK
| | - David J Gould
- Davies Veterinary Specialists, Manor Farm Business Park, Hertfordshire, UK
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Sebbag L, Mochel JP. An eye on the dog as the scientist's best friend for translational research in ophthalmology: Focus on the ocular surface. Med Res Rev 2020; 40:2566-2604. [PMID: 32735080 DOI: 10.1002/med.21716] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2020] [Revised: 07/01/2020] [Accepted: 07/15/2020] [Indexed: 12/15/2022]
Abstract
Preclinical animal studies provide valuable opportunities to better understand human diseases and contribute to major advances in medicine. This review provides a comprehensive overview of ocular parameters in humans and selected animals, with a focus on the ocular surface, detailing species differences in ocular surface anatomy, physiology, tear film dynamics and tear film composition. We describe major pitfalls that tremendously limit the translational potential of traditional laboratory animals (i.e., rabbits, mice, and rats) in ophthalmic research, and highlight the benefits of integrating companion dogs with clinical analogues to human diseases into preclinical pharmacology studies. This One Health approach can help accelerate and improve the framework in which ophthalmic research is translated to the human clinic. Studies can be conducted in canine subjects with naturally occurring or noninvasively induced ocular surface disorders (e.g., dry eye disease, conjunctivitis), reviewed herein, and tear fluid can be easily retrieved from canine eyes for various bioanalytical purposes. In this review, we discuss common tear collection methods, including capillary tubes and Schirmer tear strips, and provide guidelines for tear sampling and extraction to improve the reliability of analyte quantification (drugs, proteins, others).
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Affiliation(s)
- Lionel Sebbag
- Department of Biomedical Sciences, SMART Pharmacology, College of Veterinary Medicine, Iowa State University, Ames, Iowa, USA.,Department of Veterinary Clinical Sciences, College of Veterinary Medicine, Iowa State University, Ames, Iowa, USA
| | - Jonathan P Mochel
- Department of Biomedical Sciences, SMART Pharmacology, College of Veterinary Medicine, Iowa State University, Ames, Iowa, USA
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Sigmund AB, Ward DA, Cox SK, Hendrix DVH. Tear film concentrations of topically applied 0.5% oxytetracycline ointment in normal canine eyes. Vet Ophthalmol 2020; 23:707-713. [PMID: 32524758 DOI: 10.1111/vop.12783] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2020] [Revised: 05/07/2020] [Accepted: 05/10/2020] [Indexed: 01/20/2023]
Abstract
OBJECTIVE To determine the tear film levels of oxytetracycline in normal canine eyes after application of the ophthalmic ointment, Terramycin™ (0.5% oxytetracycline, polymyxin B sulfate), to guide appropriate treatment frequency. ANIMALS STUDIED Ten research beagles. PROCEDURES Ten research beagles with confirmed normal eyes were administered 0.02 mL of Terramycin™ ophthalmic ointment onto the dorsal bulbar conjunctival surface of the right eye. Tear samples were collected via dye-less Schirmer tear strips at 2, 4, 6, 8, and 12 hours post-administration. The sample for each timepoint was collected on a separate day, and concentrations of oxytetracycline were determined using high-performance liquid chromatography (HPLC). RESULTS There was a semi-logarithmic decline in the median tear concentration of oxytetracycline. The median (2.5th and 97.5th percentiles) tear concentrations of oxytetracycline at 2, 4, 6, 8, and 12 hours were 43.5 μg/mL (11.1-302.2 μg/mL), 28.7 μg/mL (8.04-113.7 μg/mL), 16.1 μg/mL (4.96-37.7 μg/mL), 9.2 μg/mL (4.52-28.1 μg/mL), and 6.11 μg/mL (4.36-26.7 μg/mL), respectively. Mean (±SD) drug recovery via HPLC was 88% (±7.5%). CONCLUSIONS Ophthalmic Terramycin™ achieves a substantially higher tear level than the MIC for common bacterial corneal pathogens up to 12 hours post-administration in normal eyes. Anti-collagenolytic tear levels were not achieved at the timepoints evaluated or with the manufacturer-prescribed dosing frequency. HPLC can be used to analyze tear concentrations of ophthalmic ointment formulations.
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Affiliation(s)
- Alex B Sigmund
- Small Animal Clinical Sciences, College of Veterinary Medicine, University of Tennessee, Knoxville, TN
| | - Daniel A Ward
- Small Animal Clinical Sciences, College of Veterinary Medicine, University of Tennessee, Knoxville, TN
| | - Sherry K Cox
- Biomedical and Diagnostic Sciences, College of Veterinary Medicine, University of Tennessee, Knoxville, TN
| | - Diane V H Hendrix
- Small Animal Clinical Sciences, College of Veterinary Medicine, University of Tennessee, Knoxville, TN
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Sebbag L, Yan Y, Smith JS, Allbaugh RA, Wulf LW, Mochel JP. Tear Fluid Pharmacokinetics Following Oral Prednisone Administration in Dogs With and Without Conjunctivitis. J Ocul Pharmacol Ther 2019; 35:341-349. [PMID: 31070497 PMCID: PMC6659750 DOI: 10.1089/jop.2019.0020] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Purpose: To describe the pharmacokinetics (PK) of prednisone and prednisolone in tear fluid of dogs receiving oral prednisone at anti-inflammatory to immunosuppressive doses and to assess the impact of induced conjunctivitis on lacrimal drug levels. Methods: Six healthy Beagle dogs were administered 4 courses of prednisone at 0.5, 1.0, 2.0, and 4.0 mg/kg given orally once a day for 5 days. At steady state, topical histamine was applied to induce mild (1 mg/mL) or severe (375 mg/mL) conjunctivitis in 1 eye of each dog and tear samples were collected from both eyes at selected times. Prednisone and prednisolone were quantified in tears by liquid chromatography-mass spectrometry. Results: Lacrimal prednisone and prednisolone concentrations ranged from 2 to 523 ng/mL and 5 to 191 ng/mL, respectively. Drug concentrations were overall greater in dogs receiving higher doses of prednisone, but were not correlated with tear flow rate. Eyes with conjunctivitis often had larger amounts of prednisone and prednisolone in tear fluid compared to control eyes (up to +64%), but differences were not statistically significant. Significantly greater, but clinically insignificant, levels of prednisolone were found in eyes with severe versus mild conjunctivitis for oral prednisone doses ≥1.0 mg/kg. Conclusions: Disruption of the blood-tear barrier with conjunctivitis did not significantly affect drug levels in tears. Based on drug PK in tears, oral prednisone is likely safe for the management of reflex uveitis and ocular surface diseases. However, further prospective trials using systemic corticotherapy in diseased animals are warranted to confirm findings from this preclinical study.
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Affiliation(s)
- Lionel Sebbag
- 1Department of Veterinary Clinical Sciences, College of Veterinary Medicine, Iowa State University, Ames, Iowa.,2Department of Biomedical Sciences, SMART Pharmacology, College of Veterinary Medicine, Iowa State University, Ames, Iowa
| | - Yuqi Yan
- 3Lloyd Veterinary Medical Center, College of Veterinary Medicine, Iowa State University, Ames, Iowa
| | - Joe S Smith
- 2Department of Biomedical Sciences, SMART Pharmacology, College of Veterinary Medicine, Iowa State University, Ames, Iowa.,4Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, Iowa
| | - Rachel A Allbaugh
- 1Department of Veterinary Clinical Sciences, College of Veterinary Medicine, Iowa State University, Ames, Iowa
| | - Larry W Wulf
- 5PhAST Laboratory, College of Veterinary Medicine, Iowa State University, Ames, Iowa
| | - Jonathan P Mochel
- 2Department of Biomedical Sciences, SMART Pharmacology, College of Veterinary Medicine, Iowa State University, Ames, Iowa
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Martin de Bustamante MG, Good KL, Leonard BC, Hollingsworth SR, Edwards SG, Knickelbein KE, Cooper AE, Thomasy SM, Maggs DJ. Medical management of deep ulcerative keratitis in cats: 13 cases. J Feline Med Surg 2019; 21:387-393. [PMID: 29767565 PMCID: PMC10814642 DOI: 10.1177/1098612x18770514] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
CASE SERIES SUMMARY Described are 13 cats diagnosed with deep ulcerative keratitis and successfully managed medically without grafting procedures. Typical treatment involved frequent topical application of serum and antibiotics (usually a fluoroquinolone and a cephalosporin). Seven cats also received systemic antibiotics. Analgesia was achieved using various combinations of topical atropine and systemic buprenorphine, robenacoxib or corticosteroids. Six cats were hospitalized for a median (range) period of 2.5 (1-8) days, typically because of frequent medication administration. Median (range) follow-up time was 41.5 (9-103) days. Median (range) number of recheck examinations was 4 (2-6). Median (range) time to corneal re-epithelialization was 21 (9-103) days. Median (range) topical antibiotic course was 29.5 (16-103) days. Median (range) duration of Elizabethan collar use was 28 (13-73) days. At the time of writing, no further recheck examinations were recommended for 10 cats; median (range) time between initial to final examinations in these cats was 35 (20-103) days. All cats retained the affected globes and were apparently comfortable and visual at the latest recheck examination. RELEVANCE AND NOVEL INFORMATION These cases reveal that aggressive medical management is highly successful in select cats with deep ulcerative keratitis, and can result in a cosmetically acceptable, apparently comfortable and visual globe. However, therapy is intensive with frequent administration of multiple topical and sometimes systemic medications, and requires multiple veterinary visits over many weeks. Referral to a veterinary ophthalmologist for consideration of surgical stabilization is recommended, as not all cases may be amenable to the medical therapy described here.
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Affiliation(s)
| | - Kathryn L Good
- Department of Surgical and Radiological Sciences, School of Veterinary Medicine, University of California, Davis, CA, USA
| | - Brian C Leonard
- Department of Surgical and Radiological Sciences, School of Veterinary Medicine, University of California, Davis, CA, USA
| | - Steven R Hollingsworth
- Department of Surgical and Radiological Sciences, School of Veterinary Medicine, University of California, Davis, CA, USA
| | - Sydney G Edwards
- Veterinary Medical Teaching Hospital, School of Veterinary Medicine, University of California, Davis, CA, USA
| | - Kelly E Knickelbein
- Veterinary Medical Teaching Hospital, School of Veterinary Medicine, University of California, Davis, CA, USA
| | - Ann E Cooper
- Veterinary Medical Teaching Hospital, School of Veterinary Medicine, University of California, Davis, CA, USA
| | - Sara M Thomasy
- Department of Surgical and Radiological Sciences, School of Veterinary Medicine, University of California, Davis, CA, USA
| | - David J Maggs
- Department of Surgical and Radiological Sciences, School of Veterinary Medicine, University of California, Davis, CA, USA
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Kimmitt BA, Moore GE, Stiles J. Comparison of the efficacy of various concentrations and combinations of serum, ethylenediaminetetraacetic acid, tetracycline, doxycycline, minocycline, and N-acetylcysteine for inhibition of collagenase activity in an in vitro corneal degradation model. Am J Vet Res 2018; 79:555-561. [DOI: 10.2460/ajvr.79.5.555] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Sebbag L, Showman L, McDowell EM, Perera A, Mochel JP. Impact of Flow Rate, Collection Devices, and Extraction Methods on Tear Concentrations Following Oral Administration of Doxycycline in Dogs and Cats. J Ocul Pharmacol Ther 2018; 34:452-459. [PMID: 29708819 PMCID: PMC6088255 DOI: 10.1089/jop.2018.0008] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Purpose: Compare the precision of doxycycline quantification in tear fluid collected with either Schirmer strips or polyvinyl acetal (PVA) sponges following oral drug administration. Methods: Three dogs and 3 cats were administered doxycycline orally at a dose of 4.2–5 mg/kg every 12 h for 6 consecutive days. At day 5 and 6, blood and tear fluid were sampled to capture doxycycline trough and maximal concentrations. Tear fluid was collected 3 times (spaced 10 min apart) at each session with the absorbent material placed in the lower conjunctival fornix until the 20-mm mark was reached (Schirmer strip, one eye) or for 1 min (PVA sponge, other eye). Tear extraction was performed with either centrifugation or elution in methanol. Doxycycline concentrations were measured with liquid chromatography–mass spectrometry. Low (100 ng/mL) and high (1,000 ng/mL) tear concentrations measured in vivo were spiked into each absorbent material in vitro to evaluate percentage drug recovery. Results: After oral administration of doxycycline, the drug reached the tear compartment at concentrations of 45.1–900.7 ng/mL in cats and 45.4–632.0 ng/mL in dogs, representing a tear-to-serum ratio of 12% and 16%, respectively. Doxycycline tear concentrations were significantly more precise when tear collection was performed with Schirmer strips rather than PVA sponges (P = 0.007), but were not correlated with tear flow rate. In vitro doxycycline recovery was poor to moderate (<75%). Conclusions: Schirmer strips represent a good option for lacrimal doxycycline quantification, although the collection and subsequent extraction have to be optimized to improve drug recovery.
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Affiliation(s)
- Lionel Sebbag
- 1 Department of Biomedical Sciences, Iowa State University , College of Veterinary Medicine, Ames, Iowa.,2 Department of Veterinary Clinical Sciences, Iowa State University , College of Veterinary Medicine, Ames, Iowa
| | - Lucas Showman
- 3 W.M. Keck Metabolomics Research Laboratory, Iowa State University , Ames, Iowa
| | - Emily M McDowell
- 4 Lloyd Veterinary Medical Center, Iowa State University , College of Veterinary Medicine, Ames, Iowa
| | - Ann Perera
- 3 W.M. Keck Metabolomics Research Laboratory, Iowa State University , Ames, Iowa
| | - Jonathan P Mochel
- 1 Department of Biomedical Sciences, Iowa State University , College of Veterinary Medicine, Ames, Iowa
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Sebbag L, Harrington DM, Mochel JP. Tear fluid collection in dogs and cats using ophthalmic sponges. Vet Ophthalmol 2017; 21:249-254. [DOI: 10.1111/vop.12502] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Lionel Sebbag
- Department of Veterinary Clinical Sciences; College of Veterinary Medicine; Iowa State University; Ames IA USA
| | - Danielle M. Harrington
- Lloyd Veterinary Medical Center; College of Veterinary Medicine; Iowa State University; Ames IA USA
| | - Jonathan P. Mochel
- Department of Biomedical Sciences; College of Veterinary Medicine; Iowa State University; Ames IA USA
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