Streptococcus canis sequence type 43 may be associated with treatment failure in dogs with corneal ulceration.

OBJECTIVE: To profile Streptococcus canis isolates obtained from corneal ulcers in dogs. ANIMALS: 10 dogs. PROCEDURES: Medical records were searched to identify dogs diagnosed with ulcerative keratitis by a veterinary ophthalmologist and having a positive corneal culture for S canis during the year 2020. For each case, clinical findings and outcome were determined, antimicrobial resistance and sensitivity panels were summarized, whole genome sequencing was performed, and isolates were typed using multi-locus sequence typing and genome-based proteome phylogenetic analysis. RESULTS: 10 S canis isolates were included from dogs diagnosed with ulcerative keratitis. Dogs were either treated surgically via keratectomy and conjunctival grafting (n = 6) or treated medically (4). Three of 10 corneas failed to heal and required enucleation (2/6 conjunctival grafts and 1/4 medically managed corneal ulcers). All three corneal ulcers that failed to heal were associated with S canis sequence type (ST) 43. Sequence types identified from successfully treated cases included ST8 (n = 1), ST50 (1), ST2 (2), ST27 (1), and ST15 (1). One ST43 isolate was obtained from a dog that healed following a conjunctival graft, however this was the only dog that received an oral antibiotic in addition to topical antibiotics. CLINICAL RELEVANCE: Based on this small dataset, S canis ST43 may be associated with increased virulence and contribute to conjunctival graft failure and progressive corneal collagenolysis. The postoperative administration of an oral antimicrobial may protect against conjunctival graft rejection in dogs specifically due to S canis ST43.

Phacoemulsification and intraocular lens implantation in a Canada lynx with phacoclastic uveitis.

A 4-year-old male Canada lynx (Lynx canadensis) was referred to the ophthalmology service at the University of Saskatchewan with a 7-month history of cataract and chronic phacoclastic uveitis secondary to penetrating trauma from a lynx claw. Ophthalmic examination of the right eye revealed a corneal scar, marked aqueous flare, extensive fibrovascular membranes extending from the iris to the lens, anterior and posterior synechiae, immature cataract, and anterior vitritis; the fundus was not visible. Phacoemulsification surgery and intraocular lens implantation using a custom lens of D+46 and 14 mm (An-vision, West Jordan, Utah, USA) was performed. Post-operative medications included sub-conjunctival injections of atropine, cefazolin, and triamcinolone, and oral doxycycline and prednisolone. At the 5-month follow-up, the uveitis was controlled, and a normal fundus was visualized; at 21 mo, the eye remained comfortable and visual. This is the first case report to describe phacoemulsification in a wild felid as a treatment for a traumatic cataract and severe phacoclastic uveitis. Key clinical message: Despite chronic phacoclastic uveitis, phacoemulsification surgery can provide a positive outcome for mature wild felids with traumatic lens rupture, even when topical treatment cannot be administered.

Phacoémulsification et implantation de lentilles intraoculaires chez un lynx du Canada atteint d'uvéite phacoclastique. Un lynx du Canada mâle de 4 ans (Lynx canadensis) a été référé au service d'ophtalmologie de l'University of Saskatchewan avec une histoire de 7 mois de cataracte et d'uvéite phacoclastique chronique secondaire à un traumatisme pénétrant d'une griffe de lynx. L'examen ophtalmique de l'oeil droit a révélé une cicatrice cornéenne, un phénomène de Tyndall marqué, des membranes fibrovasculaires étendues s'étendant de l'iris au cristallin, des synéchies antérieure et postérieure, une cataracte immature et une vitreite antérieure; le fond d'oeil n'était pas visible. Une chirurgie de phacoémulsification et une implantation de lentille intraoculaire à l'aide d'une lentille personnalisée de D+46 et 14 mm (An-vision, West Jordan, Utah, USA) ont été réalisées. Les médicaments postopératoires comprenaient des injections sous-conjonctivales d'atropine, de céfazoline et de triamcinolone, ainsi que de la doxycycline et de la prednisolone par voie orale. Au suivi à 5 mois, l'uvéite était contrôlée et un fond d'oeil normal était visualisé; à 21 mois, l'oeil restait confortable et visuel. Il s'agit du premier rapport de cas décrivant la phacoémulsification chez un félin sauvage comme traitement d'une cataracte traumatique et d'une uvéite phacoclastique sévère.Message clinique clé:Malgré l'uvéite phacoclastique chronique, la chirurgie de phacoémulsification peut donner un résultat positif pour les félins sauvages matures présentant une rupture traumatique du cristallin, même lorsqu'un traitement topique ne peut pas être administré.(Traduit par Dr Serge Messier).