ABSTRACT
An approximately 1.5-year-old mixed breed heifer was presented for evaluation and treatment due to ocular pain affecting the right eye secondary to a live nematode within the anterior chamber. Ophthalmic examination revealed marked blepharospasm, evidence of chronic keratitis, uveitis, and a single, white, approximately 2.5 cm long, 0.5 mm thick, living parasite. The heifer underwent general anesthesia, and the parasite was removed using passive aqueous humor outflow following a stab incision into the anterior chamber. Twenty-four hours after removal of the intraocular parasite, the heifer displayed a significant improvement in ocular comfort, corneal edema, and uveitis. The nematode was identified via genetic analyses as Parafilaria bovicola, a filarial parasite of cattle. The heifer was discharged 5 days following nematode removal with a marked improvement in all ocular signs and apparently normal vision. To the authors' knowledge, there are no previous reports of confirmed intraocular filariosis caused by P. bovicola in the veterinary literature, nor are there reports detailing surgical removal of intraocular parasites in bovids.
ABSTRACT
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.
Subject(s)
Dog Diseases , Eye Infections, Bacterial , Keratitis , Photochemotherapy , Animals , Dogs , Bayes Theorem , Corneal Cross-Linking/veterinary , Cross-Linking Reagents/therapeutic use , Dog Diseases/drug therapy , Eye Infections, Bacterial/drug therapy , Eye Infections, Bacterial/veterinary , Keratitis/drug therapy , Keratitis/veterinary , Photochemotherapy/veterinary , Photochemotherapy/methods , Photosensitizing Agents/therapeutic use , Retrospective Studies , Risk Factors , Treatment Failure , Ultraviolet RaysABSTRACT
REASON FOR PERFORMING STUDY: Keratomycosis is a severe disease in horses. Geographical differences in fungi causing keratomycosis and susceptibility of the organisms to antifungal drugs exist but few previous publications on this disease originate from Europe. OBJECTIVE: To retrospectively compare the clinical data of 36 eyes with keratomycosis, diagnosed in 35 horses between January 2000 and August 2011 at the Vetsuisse Faculty of Switzerland. Case history, season, prior treatment, clinical appearance, surgical and medical treatment, treatment duration, and globe survival were evaluated. STUDY DESIGN: Retrospective case series. METHODS: Medical records of horses with a definitive cytological or histological diagnosis of keratomycosis were reviewed. RESULTS: Thirty-one of 36 eyes (86.1%) presented with ulcerative keratitis, 2/36 (5.55%) had diffuse corneal infiltration, 2/36 (5.55%) had superficial punctate keratitis and 1/36 (2.8%) had a fluorescein-negative fungal plaque. Two of 6 fungal cultures produced Aspergillus spp. Thirty eyes received medical and surgical treatment, while 3 eyes were treated medically only. In 3 horses the globe was removed at the time of first presentation. Sex, age, prior treatment with antimicrobials or steroids, or type of surgical approach did not significantly influence the outcome. Twenty-three of 36 eyes (63.9%) were at least partially visual, 11/36 eyes (30.5%) were enucleated and 2 horses (2/36 eyes, 5.6%) were subjected to euthanasia. Treatment protocols were compared in the 31 eyes with ulcerative keratitis. In this group, 3/31 globes were immediately enucleated, 16/31 eyes were treated topically with voriconazole or voriconazole/fluconazole and 12/31 with other antifungal drug combinations. The different medication protocols did not significantly affect the outcome. CONCLUSIONS: There were no significant differences in outcome between different medical treatment protocols or types of surgical approach. POTENTIAL RELEVANCE: Future studies in central Europe should focus on the identification of fungal pathogens, susceptibility patterns and the efficacy of antifungal drug therapies.