Xanthogranulomatous keratitis in a mixed-breed dog.

OBJECTIVE: To evaluate the clinical and histopathological features of a case of xanthogranulomatous keratitis in a mixed-breed dog. ANIMAL: Mixed-breed dog. CLINICAL PRESENTATION, PROGRESSION, AND PROCEDURES: An 11-year-old spayed female mixed-breed dog was presented for mild blepharospasm, corneal cloudiness, and increasing conjunctival hyperemia OD. Ophthalmic examination revealed multifocal pink and cream-colored consolidated corneal infiltrative lesions and generalized neovascularization with suspected diagnosis of stromal abscessation. There was no improvement after 1 month of medical management, so a keratectomy was performed, and corneal tissue was sent for histopathological evaluation. TREATMENT AND OUTCOME: The nonulcerative keratitis was refractive to medical management including topical and systemic antibiotics, topical antifungal, and systemic anti-inflammatory, so keratectomy was performed. Histopathologic diagnosis of xanthogranulomatous keratitis was made 1 week postoperatively. The patient was prescribed 0.05% difluprednate ophthalmic emulsion and 0.2% tacrolimus ophthalmic ointment (initially q 8 h, OD). The difluprednate was tapered and discontinued after 2 months, but the tacrolimus was continued (q 12 h, OD). No lesion recurrence had been documented 1 year postoperatively. CLINICAL RELEVANCE: There has been little published on canine xanthogranulomas, especially in veterinary ophthalmology. Ocular xanthogranulomas have been reportedly found intraocularly and at the ocular surface. Histologically, they are characterized by well-delineated nodules that contain histiocytes and abundant lipid-laden macrophages. The treatment in this clinical case was surgical excision followed with topical immunosuppression/anti-inflammatory therapy with no recurrence 1 year postoperatively. Xanthogranulomatous keratitis should be an added differential diagnosis when nonulcerative keratitis is found on examination, specifically with consolidated, corneal infiltrate and minimal pain.

Preliminary observations on tear film interferometry performed in horses.

This retrospective study evaluated tear film (TF) interferometry on horses examined in Northern Italy in 2019-2021. The objectives were to evaluate horses affected by keratitis, and to describe TF values in horses with no evidence of ocular disease. All horses received a complete ophthalmic examination and were examined with the Ocular Surface Analyser, Veterinary-setting, prior to eye manipulation, staining and sample collection. Eighteen horses with no evidence of ocular disease were included in the comparison group. Additionally, 46 horses displaying signs of keratitis (neovascularization, corneal opacities, ulceration, epithelial and subepithelial infiltrates) were evaluated. These horses were divided into presumed non-infectious and infectious or presumed infectious keratitis groups (one with proven bacterial origin, and the others with diagnosed or presumptive keratomycosis) with the former including immune-mediated keratitis. From the observations of TF interferometry in the comparison population the authors concluded that for non-invasive break-up time (NIBUT), the estimated preliminary reference interval was 10.4-31.2s, and for tear meniscus height (TMH), it was 0.215-0.457mm. Moreover, within the keratitis population, from an interferometric point of view punctate lesions of the ocular surface were present in all cases of active diagnosed or presumptive subepithelial keratomycosis but not in any of the non-infectious cases, either non-ulcerative or ulcerative. Limitations of the study include a relatively low number of horses examined and the fact that the diagnosis of infectious keratitis was presumptive and based on clinical improvement after treatment in some cases. To the authors' knowledge, this is the first report of TF interferometry performed in horses.

Unilateral keratitis secondary to Leishmania spp. infection in a horse: Clinical signs and successful topical therapy.

Dermatological clinical signs have been seldom reported in the literature secondary to equine leishmaniasis. This case depicts the clinical signs, treatment, and outcome of a young horse with a pink, elevated lesion on the ventromedial quadrant of the cornea. A corneal cytology was performed and revealed the presence of leishmania amastigotes reaching the diagnosis of keratitis secondary to leishmania. Surgical resection was recommended but the owner declined the procedure, and the lesion was treated with a topical antimonial for 6 weeks. The lesion reduced remarkably during the first weeks of treatment. The patient had not shown recurrence of the lesion for 2 years since the treatment was started. Leishmania spp. can be responsible for ocular surface abnormalities such as keratitis. Corneal cytology is an inexpensive diagnostic method that should be considered when ocular surface abnormalities are identified in horses in endemic areas.

Bacterial and fungal isolates from 107 cases of ulcerative keratitis in Japanese Thoroughbred racehorses (2017-2021).

Infectious ulcerative keratitis is a common disease in racehorses. To improve treatment outcomes, this study aimed to assess the antimicrobial susceptibilities of bacterial and fungal isolates obtained from the cornea of Japanese Thoroughbred racehorses with equine infectious ulcerative keratitis. Bacterial and fungal cultures were performed for 166 corneal swabs from 107 cases. A disc diffusion test and minimum inhibitory concentration test were also performed to assess antimicrobial susceptibility of the bacterial and fungal isolates, respectively. Bacterial and/or fungal isolates were obtained from 85.0% (91/107) of the cases. Staphylococcus was primarily isolated from bacterial isolates, including methicillin-resistant Staphylococcus aureus (MRSA), Aerococcus, Streptococcus, Acinetobacter, and Pseudomonas. Aspergillus was primarily isolated from filamentous fungi, and Debaryomyces species was primarily identified in yeast-like fungi. Ofloxacin resistance was observed in 100% (12/12), 15.9% (7/44), and 25.0% (3/12) of MRSA, Staphylococcus, and Streptococcus isolates, respectively. The prevalence of quinolone-resistant Staphylococci and Streptococci has increased in the past two decades. All Aspergillus isolates were susceptible to voriconazole, whereas other filamentous fungi, including Fusarium, were less susceptible to voriconazole. Further studies are required to determine effective treatments for antimicrobial-resistant isolates.

Treatment of immune-mediated keratitis (IMMK) in dogs with immunosuppressants observed with spectral domain optical coherence tomography (SD-OCT).

Two dogs presented with bilateral pattern-forming corneal opacity. Treatment with topical immunosuppressants was initiated after a complete ophthalmic examination. The response to treatment was assessed by analyzing serial images using slit-lamp biomicroscopy and spectral domain optical coherence tomography (SD-OCT). Both dogs responded to topical immunosuppressants; however, the lesions recurred once the treatment was abated or withdrawn. The most effective immunosuppressant in both dogs was 0.03% tacrolimus ointment. Early and continuous treatment with topical immunosuppressants may be necessary to improve corneal clarity and prevent scarring. SD-OCT could provide useful structural information regarding presumed immune-mediated keratitis and aid in monitoring treatment response.

Evaluation of risk factors for treatment failure in canine patients undergoing photoactivated chromophore for keratitis - corneal cross-linking (PACK-CXL): a retrospective study using additive bayesian network analysis.

BACKGROUND: Infectious keratitis is a common ophthalmic condition in canine patients. Sequelae can include keratomalacia and corneal perforation, a vision threatening outcome. Photoactivated chromophore for keratitis - corneal cross-linking (PACK-CXL) is a non-surgical, adjunctive treatment method for infectious keratitis. The goal of this retrospective, multicenter study was to determine risk factors for treatment failure following PACK-CXL in canine patients suffering from suspected infectious keratitis. Medical records from four veterinary ophthalmology services were reviewed, and information related to patient demographics, ophthalmic findings, the PACK-CXL protocol used, and epithelialization time was collected and analyzed. Due to the potential for intervariable relationships, an additive Bayesian network (ABN) analysis was performed to evaluate these complex relationships. RESULTS: Records for 671 eyes (668 dogs) were included in the analysis. Based on the ABN, in the population included here, patients who underwent an accelerated PACK-CXL protocol were less likely to experience treatment failure versus patients treated with a slow protocol. Mutual dependencies between exposure variables were identified by ABN, which would have been overlooked using classical regression. Corneal re-epithelialization time was shortened following PACK-CXL combined with topical medical therapy compared to PACK-CXL alone. CONCLUSIONS: No risk factors associated with treatment failure were identified in the population included in the present study. Canine patients may benefit from the use of accelerated PACK-CXL protocols, especially when combined with topical antibiotics and anti-collagenolytic therapy. The reasons for this apparent positive impact on treatment outcome remain unclear.

Use of Biologics and Stem Cells in Equine Ophthalmology.

Regenerative therapy and biologics have the promise to treat equine ocular surface diseases, including corneal ulceration or immune-mediated keratitis, or intraocular diseases such as uveitis. The use of blood-derived products such as serum or platelet-rich plasma, mesenchymal stem cells, or amniotic membrane grafts may be beneficial for the treatment of ulcerative and chronic keratitis in horses. Furthermore, the use of stem cells or gene therapy has promise for the treatment of Intraocular diseases such as equine recurrent uveitis by providing efficacious, practical, and long-term therapy for these blinding diseases.

A case of Candida albicans-induced fungal keratitis in a Chihuahua dog - with a focus on optical coherence tomographic features.

A 4-year-old Chihuahua dog was referred for bilateral corneal ulcers. Slightly raised white fluorescein-positive plaque-like corneal lesions in both eyes appeared as intense hyperreflective areas with posterior shadowing on optical coherence tomography (OCT). Based on corneal cytology and culture, Candida albicans-induced fungal keratitis was diagnosed. Despite treatment, on OCT, endothelial plaques, increased stromal infiltration thickness, vertical shapes of the ulcer edge, and necrotic stromal space were judged to be aggravation of the disease, and surgery was performed. Conjunctival grafting surgery with topical 1% voriconazole effectively resolved fungal keratitis. OCT can provide detailed and objective information related to the disease prognosis.

IN VIVO CONFOCAL MICROSCOPY FOR CHARACTERIZATION OF MYCOTIC KERATITIS IN OWLS (BUBO SCANDIACUS, STRIX VARIA) AND A WOODCOCK (SCOLOPAX MINOR): THREE CASES.

This case series describes the use of in vivo confocal microscopy in the diagnosis and treatment of mycotic keratitis in two owls (one Bubo scandiacus, one Strix varia) and one woodcock (Scolopax minor). Each bird was at increased risk of fungal infection due to recent injury or stress. Ophthalmic findings in all birds included blepharospasm, ocular discharge, ulcerative keratitis, white or yellow corneal plaques, and anterior uveitis. Fungal hyphae were identified in corneal samples from all three eyes examined cytologically and in all three eyes by using in vivo confocal microscopy. Aspergillus fumigatus was isolated from a corneal culture in one bird. Despite medical treatment, progressive ocular disease prompted enucleation in two birds. Fungal hyphae were detected by histopathology in one of the two enucleated eyes. In vivo confocal microscopy aided the diagnosis of fungal keratitis in all birds and was the only diagnostic method that allowed immediate, real-time quantification of the extent (area and depth) and severity of mycotic keratitis.

PLDLA/TPU Matrix Enriched with Cyclosporine A as a Therapeutic Platform for Immune-Mediated Keratitis (IMMK) in Horses.

The purpose of this study was to describe the use of PLDLA/TPU matrix enriched with cyclosporine A (CsA) as a therapeutic platform in horses with immune-mediated keratitis (IMMK) with an in vitro evaluation CsA release and degradation of the blend as well as determination of the safety and efficacy of that platform used in the animal model. The kinetics of the CsA release from matrices constructed of thermoplastic polyurethane (TPU) polymer and a copolymer of L-lactide with DL-lactide (PLDLA) (80:20) in the TPU (10%) and a PLDL (90%) polymer blend were studied. Moreover, we used the STF (Simulated Tear Fluid) at 37 °C as a biological environment to assess the CsA release and its degradation. Additionally, the platform described above was injected subconjunctival in the dorsolateral quadrant of the globe after standing sedation of horses with diagnosed superficial and mid-stromal IMMK. The obtained results indicated that the CsA release rate in the fifth week of the study increased significantly by the value of 0.3% compared to previous weeks. In all of the cases, the TPU/PLA doped with 12 mg of the CsA platform effectively reduced the clinical symptoms of keratitis, leading to the complete remission of the corneal opacity and infiltration four weeks post-injection. The results from this study showed that the PLDLA/TPU matrix enriched with the CsA platform was well tolerated by the equine model and effective in treating superficial and mid-stromal IMMK.

Keratouveitis in juvenile dogs and its presumed association with canine adenovirus infection.

OBJECTIVE: We hypothesized that keratouveitis still occurs despite current widespread use of Canine adenovirus (CAV)-2 vaccinations and assessed the utility of CAV-1 and CAV-2 titers in elucidation of its etiopathogenesis. ANIMALS STUDIED: Nine dogs with unexplained keratouveitis (14 eyes) and nine control dogs. PROCEDURES: The Animal Health Trust clinical database was searched between 2008 and 2018 to identify cases of keratouveitis. Inclusion criteria included known vaccination status, interval from vaccination to development of clinical signs and availability of CAV titers. Cases were excluded if they were older than 1 year of age, or other causative ocular pathology for corneal edema was identified. Nine age-matched dogs without corneal edema but with CAV titers were included as controls. RESULTS: Mean CAV-1 and CAV-2 titers were not statistically different between dogs with keratouveitis and controls (p = .16 and p = .76, respectively). Three cases had CAV-1 titers >5000 and two of these cases had rising convalescence titers (greater than an 11-fold increase) suggesting infection with wild-type CAV-1. The six other cases did not appear to be associated with CAV infection or vaccination. CONCLUSION: Keratouveitis continues to occur despite the advent of CAV-2 vaccinations. While this study found no evidence to indicate CAV-2 vaccination causes keratouveitis, the data indicates that in a proportion of cases, contemporaneous wild-type CAV-1 infection is a possible cause.

Nocardia and Streptomyces keratitis in dogs: In vivo detection of filamentous bacteria by confocal microscopy.

OBJECTIVE: To describe the clinical features of dogs with Nocardia and Streptomyces keratitis, including the results of in vivo confocal microscopy examinations. ANIMAL STUDIED: A 15-year-old, male-castrated, miniature Schnauzer was presented with a multilobulated, cystic, pink, ulcerated corneal mass with surrounding dense leukocyte infiltrates. Cytologic evaluation of a corneal scraping identified pyogranulomatous inflammation and filamentous bacteria. Nocardia nova was cultured from corneal samples. Anterior lamellar keratectomy was performed to excise the affected corneal region and histopathologic evaluation confirmed the diagnosis of pyogranulomatous keratitis. A 10-year-old, male-castrated, Yorkshire terrier was presented for evaluation of a chronic anterior stromal corneal ulcer associated with a brown corneal plaque. Cytologic evaluation of a corneal scraping identified suppurative inflammation and filamentous bacteria. A Streptomyces sp. was cultured from corneal samples. The keratitis in both dogs resolved with therapy. PROCEDURES: In vivo confocal microscopy examination of the corneal lesions in both dogs revealed dense accumulations of leukocytes and clusters of hyperreflective, slender, branching bacterial structures that were approximately 1.5-2.0 µm in diameter and 25-50 µm in length. Confocal microscopy imaging of the Nocardia isolate in vitro, and ex vivo canine corneas experimentally infected with the bacteria, was performed to corroborate the in vivo findings. The morphology of the filamentous bacteria was similar between the in vivo, in vitro, and ex vivo confocal microscopy examinations. CONCLUSIONS AND CLINICAL RELEVANCE: Nocardia and Streptomyces spp. can be associated with infectious keratitis in dogs. In vivo detection of filamentous bacteria in the cornea can be accomplished by confocal microscopy.

Susceptibility pattern of bacterial isolates in equine ulcerative keratitis: Implications for empirical treatment at a university teaching hospital in Sydney.

Corneal ulceration is a common ophthalmic condition in horses. It is frequently caused by trauma to the corneal surface, followed by secondary infection by commensal or pathogenic organisms including Streptococcus equi subspecies zooepidemicus, Pseudomonas aeruginosa and Staphylococcus spp. Emerging antimicrobial resistance amongst these organisms has raised the need for appropriate antimicrobial therapy selection, to optimise treatment efficacy while minimising further antimicrobial resistance. Medical records of 38 horses presented at the University Veterinary Teaching Hospital Camden for ulcerative keratitis between 2010 and 2020 were reviewed to identify those with positive bacterial cultures and antimicrobial susceptibility profiles (13/38). Common susceptibility patterns were identified and used to guide the empirical treatment of equine bacterial corneal ulcers. Pseudomonas spp. (64.3%), Streptococcus equi subspecies zooepidemicus (14.3%) and Actinobacillus spp. (14.3%) were most commonly identified. Susceptibility to amikacin, gentamicin and ciprofloxacin was observed in 100%, 66.7% and 85.7% Pseudomonas spp. isolates respectively. Resistance to polymyxin B and neomycin occurred in 85.7% and 71.4% of Pseudomonas spp., respectively. All Streptococcus equi subspecies zooepidemicus organisms in this study were susceptible to ceftiofur, cephalexin, penicillin and ampicillin, while they were all resistant to gentamicin, neomycin, enrofloxacin and marbofloxacin. Predominating in this study, Pseudomonas spp. maintained overall aminoglycoside susceptibility despite some emerging resistance, and good fluoroquinolone susceptibility. High resistance to Polymyxin B could have arisen from its common use as first-line therapy for bacterial corneal ulcers. Although further research is required, these new findings about predominant bacteria in equine corneal ulceration in the Camden region and their antimicrobial susceptibility patterns can be used to guide the empirical treatment of bacterial corneal ulcers in horses.

Effects of commercial amniotic membrane extract on the re-epithelialization time and the early expression of matrix metalloproteinase-9 in cats with experimentally induced corneal ulcers.

OBJECTIVES: To investigate whether a commercially available amniotic membrane extract (AME) can accelerate corneal wound healing and suppress the early expression of MMP-9 in the tears of cats with experimentally induced superficial ulcerative keratitis. PROCEDURES: A total number of 16 cats were included. At the end of keratectomy, cats in the treatment group (TG, n = 8) received 40 µl of AME (EyeQ® Amniotic Eye Drops, Vetrix®) four times daily, while cats in the control group (CG, n = 8) received 40 µl of saline at the same time points. Tears were collected 24 and 48 h after keratectomy, and the total MMP-9 was quantified by ELISA. RESULTS: The corneal re-epithelialization rate did not differ between groups (p = .26), being 0.48 ± 0.05 mm2 /h in the CG and 0.41 ± 0.03 mm2 /h in the TG. Similarly, the average time to achieve corneal wound healing did not differ between groups (p = .25) and was 61.50 ± 3.54 h in the CG and 70.50 ± 6.71 h in the TG. The dimensions of the ulcerated areas also did not differ at any time point between the groups (p > .05). In both groups, corneas healed without scarring, pigmentation, or vascularization. The expression of MMP-9 in the tears was similar in both groups at 24 h post-keratectomy, with a slight decrease at 48 h (p > .05). CONCLUSIONS: The instillation of a commercial AME (EyeQ®) is safe, but it did not decrease the corneal re-epithelialization time or the early expression of MMP-9 in the tears of cats with experimentally induced superficial ulcerative keratitis in this study.

Molecular characterization of fungal endophthalmitis and keratitis caused by yeasts.

Candida species are the most common causes of sight-threatening fungal ocular infections in temperate regions of the world. Despite their relevance, little is known about the emergence of novel species and the molecular epidemiology of these infections. Here, we molecularly characterized 38 yeast isolates collected from patients diagnosed with endophthalmitis or keratitis at Massachusetts Eye and Ear from 2014 to 2021. Sequencing of the ITS1-5.8S-/ITS2 regions demonstrated that this population of yeasts was dominated by Candida spp. (37 out of 38; 97%), with 58% of the cases caused by C. albicans (n = 22) and the remaining by emerging non-albicans species, predominantly by C. parapsilosis (n = 8) and C. dubliniensis (n = 6). One isolate each was identified as C. tropicalis and Clavispora lusitaniae. Interestingly, all C. dubliniensis were isolated from endophthalmitis and most C. parapsilosis from keratitis. Multilocus sequence typing analysis of C. albicans showed a prevalence of CC-1 isolates that has DST69 as the putative founder, with 64% of them belonging to this clonal complex (CC). Isolates grouped within this cluster were more predominant in endophthalmitis (10 out of 14; 71%). One C. albicans CC-1 isolate was multi-azole resistant. In conclusion, we observed that nearly half of the ocular infections caused by yeasts are associated with C. albicans, with evidence for the emergence of non-albicans species that are differentially enriched in distinct ocular niches. Candida albicans isolates clustered within the predominant CC-1 group were particularly more common in endophthalmitis, demonstrating a potential pattern of ocular disease enrichment within this clade.

Candida species are the most common pathogen responsible for ocular infections in the temperature regions of the world. Here, we sequenced and molecularly characterized the Candida species seen in patients who present to our hospital with infection to understand the species' distribution over time.

Developing advanced therapeutics through the study of naturally occurring immune-mediated ocular disease in domestic animals.

This review, which is part of the "Currents in One Health" series, describes the importance of the study of immune-mediated ocular disease in the development of innovative therapeutics, such as cell and gene therapy for the eye. Recent examples of cell and gene therapy studies from the author's laboratory are reviewed to emphasize the importance of One Health initiatives in developing innovative therapies for ocular diseases. Spontaneous immune-mediated corneal disease is common in horses, cats, dogs, and humans. Autologous bone marrow-derived mesenchymal stem cells (BM-MSCs) injected subconjunctivally resulted in the resolution of naturally occurring immune-mediated keratitis (IMMK) without adverse effects. These results support that autologous subconjunctival BM-MSC therapy may be a viable treatment alternative for IMMK. Furthermore, the use of subconjunctival MSCs may be an effective method to treat ocular surface immune-mediated diseases in humans and other species, including herpetic stromal keratitis and immunologic dry eye disease. Furthermore, the use of adeno-associated viral (AAV) vectors to deliver the immunosuppressive transgene cDNA of equine interleukin 10 (eqIL-10) or human leukocyte antigen G injected intravitreally was shown to be safe and inhibited the development of uveitis in the experimental autoimmune uveitis rat model. Efficacy and safety studies of ocular gene therapy in models will pave the way for clinical trials in animals with naturally occurring immune-mediated diseases, such as a therapeutic clinical trial for AAV-eqIL-10 in horses with equine recurrent uveitis.

The bactericidal effect of two photoactivated chromophore for keratitis-corneal crosslinking protocols (standard vs. accelerated) on bacterial isolates associated with infectious keratitis in companion animals.

BACKGROUND: Bacterial corneal infections are common and potentially blinding diseases in all species. As antibiotic resistance is a growing concern, alternative treatment methods are an important focus of research. Photoactivated chromophore for keratitis-corneal crosslinking (PACK-CXL) is a promising oxygen radical-mediated alternative to antibiotic treatment. The main goal of this study was to assess the anti-bactericidal efficacy on clinical bacterial isolates of the current standard and an accelerated PACK-CXL treatment protocol delivering the same energy dose (5.4 J/cm2). METHODS: Clinical bacterial isolates from 11 dogs, five horses, one cat and one guinea pig were cultured, brought into suspension with 0.1% riboflavin and subsequently irradiated. Irradiation was performed with a 365 nm UVA light source for 30 min at 3mW/cm2 (standard protocol) or for 5 min at 18mW/cm2 (accelerated protocol), respectively. After treatment, the samples were cultured and colony forming units (CFU's) were counted and the weighted average mean of CFU's per µl was calculated. Results were statistically compared between treated and control samples using a linear mixed effects model. RESULTS: Both PACK-CXL protocols demonstrated a significant bactericidal effect on all tested isolates when compared to untreated controls. No efficacy difference between the two PACK-CXL protocols was observed. CONCLUSION: The accelerated PACK-CXL protocol can be recommended for empirical use in the treatment of bacterial corneal infections in veterinary patients while awaiting culture results. This will facilitate immediate treatment, the delivery of higher fluence PACK-CXL treatment within a reasonable time, and minimize the required anesthetic time or even obviate the need for general anesthesia.

Genome-Wide Association Analysis for Chronic Superficial Keratitis in the Australian Racing Greyhound.

Chronic superficial keratitis (CSK) is a progressive inflammatory condition of the eye (cornea) that can cause discomfort and blindness. Differential disease risk across dog breeds strongly suggests that CSK has a genetic basis. In addition to genetic risk, the occurrence of CSK is exacerbated by exposure to ultraviolet light. Genome-wide association analysis considered 109 greyhounds, 70 with CSK and the remainder with normal phenotype at an age over four years. Three co-located variants on CFA18 near the 5' region of the Epidermal Growth Factor Receptor (EGFR) gene were associated with genome-wide significance after multiple-test correction (BICF2P579527, CFA18: 6,068,508, praw = 1.77 × 10-7, pgenome = 0.017; BICF2P1310662, CFA18: 6,077,388, praw = 4.09 × 10-7, pgenome = 0.040; BICF2P160719, CFA18: 6,087,347, praw = 4.09 × 10-7, pgenome = 0.040) (canFam4)). Of the top 10 associated markers, eight were co-located with the significantly associated markers on CFA18. The associated haplotype on CFA18 is protective for the CSK condition. EGFR is known to play a role in corneal healing, where it initiates differentiation and proliferation of epithelial cells that in turn signal the involvement of stromal keratocytes to commence apoptosis. Further validation of the putative functional variants is required prior to their use in genetic testing for breeding programs.

Comparison of corneal culture results obtained using the ESwab™ and Amies charcoal swab in canine and feline patients.

OBJECTIVE: The objective of the study was to compare corneal culture results using the ESwab™ and Amies charcoal swab. ANIMALS STUDIED: One hundred fourteen canine and fifteen feline eyes. PROCEDURES: Retrospective analysis of Dick White Referrals bacterial and fungal corneal culture data was conducted. Results were included from canine and feline patients, which presented with suspected infectious keratitis that had samples taken using an Amies charcoal swab followed by an ESwab™ in the same eye. In respect to positive and negative cultures, a McNemar test was conducted comparing instances of disagreement between swab types, and the Kappa coefficient (κ) was calculated to assess the level of agreement between swab types. RESULTS: The ESwab™ produced more positive corneal cultures (71/129 [55.0%]) than the Amies charcoal swab (41/129 [31.8%]). 2/129 eyes produced positive fungal cultures. Considering 37/129 eyes in which both swab types detected a positive corneal culture, the same bacterial species were cultured from each swab type in 34/37 (91.9%) eyes, and an additional bacterial species was cultured by the ESwab™ in 3/37 (8.1%) eyes. In 34/38 (89.5%), instances of disagreement between swab types, the ESwab™ showed a positive culture, and the Amies charcoal swab showed a negative culture from the same eye, and this difference was significant (p < 0.0001). There was a moderate level of agreement between results from both swab types (κ = 0.432). CONCLUSIONS: ESwab™ sampling alone may be superior to Amies charcoal swabs for detecting presence of bacteria in suspected infectious keratitis in cats and dogs.

Prevalence and characteristics of ocular diseases in Sphynx cats: A retrospective assessment (2012-2021) and comparison with non-Sphynx cats.

PURPOSE: To describe the prevalence of ocular diseases in Sphynx cats, and compare disease characteristics with other feline breeds. METHODS: Medical records of Sphynx cats presented to an ophthalmology referral center between 1/2012 and 4/2021 were examined. Cats of other breeds examined during the same period served as controls. RESULTS: One hundred ten Sphynx cats were examined during the study period, diagnosed with corneal sequestrum (n = 42 cats), lower eyelid entropion (n = 25), presumed herpetic keratoconjunctivitis (n = 19), conjunctivitis (n = 7), corneal ulcers (n = 6), nasolacrimal duct atresia/obstruction (n = 6), corneal dystrophy (n = 3), eosinophilic keratitis (n = 2), uveitis (n = 2), non-ulcerative keratitis (n = 1), and cataract (n = 1). Corneal sequestrum was significantly more common in Sphynx versus non-Sphynx cats (odds ratio = 8.0, 95% CI = 5.3-12.2, p < .001), and age of diagnosis was significantly younger in Sphynx cats (2.0 ± 1.5 years vs. 5.9 ± 4.0 years, p < .001). Corneal sequestrum recurrence was noted in 19.4% Sphynx eyes and 6.4% non-Sphynx eyes undergoing surgery (p = .015). Lower eyelid entropion-most often bilateral (80%)-was significantly more common in Sphynx versus non-Sphynx cats (odds ratio = 4.1, 95% CI = 2.3-7.1, p < .001), and age of diagnosis was significantly younger in Sphynx cats (0.9 ± 1.4 years vs. 3.5 ± 3.3 years, p < .005). CONCLUSIONS: Corneal sequestrum and entropion were overrepresented and diagnosed at an earlier age in Sphynx cats when compared with the general feline population. Given the high prevalence, early age of onset, and relatively high recurrence of corneal sequestrum in Sphynx cats, further studies are warranted to better understand etiopathogenesis and preferred therapies.