Equine uveitis: Outcome and adverse effects after one or two intravitreal low-dose gentamicin injections.

Moru00e9n, S
·
Kallberg, M
·
Strom, L

Abstract: Uveitis is common in horses, potentially turning chronic (persistent or recurrent) resulting in impaired vision or blindness. All mainstay therapeutics aims at controlling inflammation, but long-term or lifelong treatment is often needed with possibly severe side effects. Therefore, intravitreal injections with low-dose gentamicin (IVGI) have been used in attempt to give a long-lasting result with potentially less side effects. Objective: To retrospectively assess outcome and long-term complications following one or two low-dose IVGI in Swedish horses with chronic uveitis. Methods: Retrospective case series. Methods: Medical records of horses diagnosed with uveitis examined at the Equine Clinic of the University Animal Hospital of Sweden between 2016 and 2021 were reviewed. Inclusion criteria were horses with a diagnosis of chronic uveitis that were treated with 4 mg IVGI. After injection, tapering doses of anti-inflammatory medications were administered. Due to persistence or recurrence of uveitis despite IVGI, some horses received a second injection. A positive outcome was defined as controlled uveitis, despite no or minimal anti-inflammatory medication. Results: 32 eyes (29 horses) were included. Based on clinical evaluation, uveitis was classified as anterior (91%) or panuveitis (9%). 10 eyes were treated with IVGI twice. A positive outcome was observed in 13/32 eyes (41%). Inflammation in 9/32 eyes was controlled after the first, and in 4/10 eyes after the second IVGI treatment. Long-term complications included retinal degeneration in seven eyes, and mature cataracts in five eyes. Enucleations were performed in 14/32 eyes, due to lack of favourable response of IVGI, or due to complications, that is, glaucoma, corneal ulceration, and/or corneal mineralisation. One horse was euthanised due to painful bouts of inflammation in both eyes despite treatment. Conclusions: Small sample size, retrospective design with no control group, no histopathology performed, infrequent sampling for Leptospira and no standardised treatment protocol after the IVGI. Conclusions: In this group of Swedish horses, predominantly diagnosed clinically with anterior uveitis, a positive outcome was observed in 41% of eyes following one or two low-dose IVGI. Retinal degeneration in the visual streak was observed in 22% of eyes, which is a higher proportion of this complication than previously described.

Get Full Text

Publication Date: 2024-02-08 PubMed ID: 38329024DOI: 10.1111/evj.14056Google Scholar: Lookup

The Equine Research Bank provides access to a large database of publicly available scientific literature. Inclusion in the Research Bank does not imply endorsement of study methods or findings by Mad Barn.

Facebook X LinkedIn Email

Summary
Cite This
Publication
Affiliations
References
Citations

Journal Article

Summary

This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.

The research aims to study the impact of one or two intravitreal injections of low-dose gentamicin (IVGI) in treating chronic uveitis in horses, and explores the long-term complications of this treatment.

Methodology

The researchers conducted a retrospective analysis of medical records of Swedish horses treated at the Equine Clinic of the University Animal Hospital between 2016 and 2021.
The inclusion criteria for the study were horses diagnosed with chronic uveitis that were treated with a 4-milligram dosage of IVGI. Some horses received a second IVGI injection due to persistence or recurrence of uveitis.
A “positive outcome” was defined as controlled uveitis with little to no anti-inflammatory medication.

Results

A total of 32 eyes from 29 horses were included in the study. Uveitis was categorized as anterior in 91% of cases and panuveitis in 9% of cases.
10 eyes were treated with two doses of IVGI. A positive outcome was observed in 41% of the treated eyes. 9 of these were controlled after the first dose and 4 after the second dose.
Long-term complications included retinal degeneration in seven eyes and mature cataracts in five. Furthermore, 14 eyes had to be enucleated, or removed, due to adverse effects such as glaucoma, corneal ulceration, and corneal mineralisation or lack of response to the IVGI treatment. A single horse had to be euthanised because of painful recurrent bouts of eye inflammation despite undergoing the treatment.

Conclusions

The study had several limitations including a small sample size, lack of a control group, absence of histopathology, infrequent Leptospira sampling, and no standardised post-IVGI treatment protocol.
Nevertheless, among the group of Swedish horses predominantly diagnosed with anterior uveitis, it was found that 41% of eyes responded positively to one or two low-dose IVGI treatments.
Retinal degeneration was observed in 22% of treated eyes, a rate higher than previously described, indicating a possible adverse effect of this treatment mechanism.

Cite This Article

APA

Moru00e9n S, Kallberg M, Strom L. (2024). Equine uveitis: Outcome and adverse effects after one or two intravitreal low-dose gentamicin injections. Equine Vet J. https://doi.org/10.1111/evj.14056

Publication

Equine veterinary journal

ISSN: 2042-3306

NlmUniqueID: 0173320

Country: United States

Language: English

Researcher Affiliations

Moru00e9n, S

Equine Clinic, University Animal Hospital, Swedish University of Agricultural Sciences, Uppsala, Sweden.

Kallberg, M

Equine Clinic, University Animal Hospital, Swedish University of Agricultural Sciences, Uppsala, Sweden.

Strom, L

Equine Clinic, University Animal Hospital, Swedish University of Agricultural Sciences, Uppsala, Sweden.

References

This article includes 40 references

Gilger BC, Michau TM. Equine recurrent uveitis: new methods of management. Vet Clin North Am Equine Pract. 2004;20(2):417-427. vii.
Schwink KL. Equine uveitis. Vet Clin North Am Equine Pract. 1992;8(3):557-574.
Gilger B. Equine recurrent uveitis: the viewpoint from the USA. Equine Vet J. 2010;42(S37):57-61.
Gerding JC, Gilger BC. Prognosis and impact of equine recurrent uveitis. Equine Vet J. 2016;48(3):290-298.
Gilger BC, Wilkie DA, Clode AB, McMullen RJ Jr, Utter ME, Komaromy AM, et al. Long-term outcome after implantation of a suprachoroidal cyclosporine drug delivery device in horses with recurrent uveitis. Vet Ophthalmol. 2010;13(5):294-300.
Dwyer AE, Crockett R, Kalsow CM. Association of leptospiral seroreactivity and breed with uveitis and blindness in horses: 372 cases (1986-1993). J Am Vet Med Assoc. 1995;207(10):1327-1331.
Deeg CA. Ocular immunology in equine recurrent uveitis. Vet Ophthalmol. 2008;11:61-65.
Malalana F, Stylianides A, McGowan C. Equine recurrent uveitis: human and equine perspectives. Vet J. 2015;206(1):22-29.
Gilger BC, Malok E, Stewart T, Horohov D, Ashton P, Smith T, et al. Effect of an intravitreal cyclosporine implant on experimental uveitis in horses. Vet Immunol Immunopathol. 2000;76(3-4):239-255.
Pinto NI, McMullen RJ, Linder KE, Cullen JM, Gilger BC. Clinical, histopathological and immunohistochemical characterization of a novel equine ocular disorder: heterochromic iridocyclitis with secondary keratitis in adult horses. Vet Ophthalmol. 2015;18(6):443-456.
McMullen RJ Jr, Fischer BM. Medical and surgical management of equine recurrent uveitis. Vet Clin North Am Equine Pract. 2017;33(3):465-481.
Spiess B. Equine recurrent uveitis: the European viewpoint. Equine Vet J. 2010;42(S37):50-56.
Fruu00e8hauf B, Ohnesorge B, Deegen E, Boeve M. Surgical management of equine recurrent uveitis with single port pars plana vitrectomy. Vet Ophthalmol. 1998;1(2-3):137-151.
Gerhards H, Wollanke B, Brem S. Vitrectomy as a diagnostic and therapeutic approach for equine recurrent uveitis (ERU). Proc Am Assoc Equine Practnrs. 1999;45:89-93.
Toemoerdy E, Haessig M, Spiess BM. The outcome of pars plana vitrectomy in horses with equine recurrent uveitis with regard to the presence or absence of intravitreal antibodies against various serovars of Leptospira interrogans. Pferdeheilkunde. 2010;26(2):251-254.
Gilger BC, Wilkie DA, Davidson MG, Allen JB. Use of an intravitreal sustained-release cyclosporine delivery device for treatment of equine recurrent uveitis. Am J Vet Res. 2001;62(12):1892-1896.
Pinard C, Piu00e8trement E, Macieira S, Tremblay D, editors. Intravitreal injections of gentamicin for the treatment of Leptospira-associated equine recurrent uveitis. 36th Annual Meeting of the ACVO; Nashville, TN 2005.
Fischer BM, McMullen RJ, Reese S, Brehm W. Intravitreal injection of low-dose gentamicin for the treatment of recurrent or persistent uveitis in horses: preliminary results. BMC Vet Res. 2019;15(1):1-12.
Launois T, Gonzu00e1lez Hilariu00f3n LM, Barbe F, Leurquin C, Bihin B, Hontoir F, et al. Use of intravitreal injection of gentamicin in 71 horses with equine recurrent uveitis. J Equine Vet. 2019;77:93-97.
Kleinpeter A, Goepfert A, Koehler E, Brehm W. Intravitreal injection of low-dose gentamicin for the treatment of ERU-affected horses. Tieraerztliche Praxis Ausgabe Grosstiere Nutztiere. 2019;47(1):25-34.
Smith HL, Berglund AK, Robertson JB, Schnabel LV, McMullen RJ Jr, Gilger BC, et al. Effect of gentamicin on CD3+ T-lymphocyte proliferation for treatment of equine recurrent uveitis: an in vitro study. Vet Ophthalmol. 2023;26(4):347-354.
Peyman GA, May DR, Ericson ES, Apple D. Intraocular injection of gentamicin: toxic effects and clearance. Arch Ophthalmol. 1974;92(1):42-47.
McDonald HR, Schatz H, Allen AW, Chenoweth RG, Cohen HB, Crawford JB, et al. Retinal toxicity secondary to intraocular gentamicin injection. Ophthalmology. 1986;93(7):871-877.
Burkholder BM, Jabs DA. Uveitis for the non-ophthalmologist. BMJ. 2021;372:m4979.
Kok H, Lau C, Maycock N, McCluskey P, Lightman S. Outcome of intravitreal triamcinolone in uveitis. Ophthalmology. 2005;112(11):1916. e1-7.
Nguyen QD, Ibrahim MA, Watters A, Bittencourt M, Yohannan J, Sepah YJ, et al. Ocular tolerability and efficacy of intravitreal and subconjunctival injections of sirolimus in patients with non-infectious uveitis: primary 6-month results of the SAVE study. J Ophthalmic Inflamm Infect. 2013;3(1):1-15.
Nguyen QD, Merrill PT, Sepah YJ, Ibrahim MA, Banker A, Leonardi A, et al. Intravitreal sirolimus for the treatment of noninfectious uveitis: evolution through preclinical and clinical studies. Ophthalmology. 2018;125(12):1984-1993.
u00d6zkiris A. Intravitreal triamcinolone acetonide injection for the treatment of posterior uveitis. Ocul Immunol Inflamm. 2006;14(4):233-238.
Petroutsos G, Savoldelli M, Pouliquen Y. The effect of gentamicin on the corneal endothelium An experimental study. Cornea. 1990;9(1):62-65.
Verma A, Stevenson B, Adler B. Leptospirosis in horses. Vet Microbiol. 2013;167(1-2):61-66.
Williams RD, Morter RL, Freeman MJ, Lavignette AM. Experimental chronic uveitis - ophthalmic signs following equine leptospirosis. Invest Ophthalmol. 1971;10(12):948.
Frellstedt L. Equine recurrent uveitis: a clinical manifestation of leptospirosis. Equine Vet Educ. 2009;21(10):546-552.
Bharti AR, Nally JE, Ricaldi JN, Matthias MA, Diaz MM, Lovett MA, et al. Leptospirosis: a zoonotic disease of global importance. Lancet Infect Dis. 2003;3(12):757-771.
Baverud V, Gunnarsson A, Engvall EO, Franzen P, Egenvall A. Leptospira seroprevalence and associations between seropositivity, clinical disease and host factors in horses. Acta Vet Scand. 2009;51:15.
SVA NVI. Leptospiros hos hu00e4st. 2022 Available from: https://www.sva.se/amnesomraden/djursjukdomar-a-o/leptospiros-hos-hast/
Thomas T, Galiani D, Brod R. Gentamicin and other antibiotic toxicitiy. Ophthalmol Clin North Am. 2001;14(4):611-624.
Brown GC, Eagle RC, Shakin EP, Gruber M, Arbizio VV. Retinal toxicity of intravitreal gentamicin. Arch Ophthalmol. 1990;108(12):1740-1744.
Gilger BC, Reeves KA, Salmon JH. Ocular parameters related to drug delivery in the canine and equine eye: aqueous and vitreous humor volume and scleral surface area and thickness. Vet Ophthalmol. 2005;8(4):265-269.
Brooks D. Calcium degeneration and ocular surface failure in the horse. Equine Vet Educ. 2012;24(1):8-11.
Berryhill EH, Thomasy SM, Kass PH, Reilly CM, Good KL, Hollingsworth SR, et al. Comparison of corneal degeneration and calcific band keratopathy from 2000 to 2013 in 69 horses. Vet Ophthalmol. 2017;20(1):16-26.