Conjunctivitis and ulcerative keratitis secondary to conjunctival plant foreign bodies in a herd of alpacas (Lama Pacos)

Purpose To describe six cases of conjunctivitis and ulcerative keratitis secondary to plant foreign bodies from weed‐contaminated grass hay which were lodged within the temporal conjunctival fornix in a herd of alpacas. Methods A total of 21 alpacas from the same farm developed blepharospasm and mucopurulent ocular discharge. Six of the 21 were evaluated at the University of Tennessee College of Veterinary Medicine within a 2‐week period. The six animals evaluated received an ophthalmic examination including slit‐lamp biomicroscopy, fluorescein staining, and topical corneal anesthesia for foreign body removal when necessary. Results Six animals had conjunctivitis characterized by hyperemia and mucopurulent discharge. Five animals had superficial ulcerative keratitis with intense corneal neovascularization and edema. In all cases, the keratitis was located at the temporal limbus. Seven plant foreign bodies were observed and were removed following topical corneal anesthesia in five animals. The plant seeds were identified as three common weed species found in orchard grass hay. Complete resolution of all clinical signs was achieved with foreign body removal and medical therapy. Conclusions Fan‐shaped temporal corneal ulcers may signify the presence of conjunctival foreign bodies in alpacas. Plant foreign bodies should be considered in addition to ocular infection when multiple animals of a herd are affected as outbreaks may occur with weed‐contaminated hay.     

Outbreak of ocular disease associated with naturally-acquired canine herpesvirus-1 infection in a closed domestic dog colony

Objective  To describe clinical and virological findings of an outbreak of ocular disease attributed to naturally-acquired primary canine herpesvirus-1 (CHV-1) infection in a closed domestic dog colony.
Animals studied  Twenty-seven 10- to 16-week-old laboratory Beagles.
Procedure  Complete ophthalmic examinations were performed and ocular samples collected for CHV-1 polymerase chain reaction and virus isolation.
Results  The prevalence of ocular morbidity was 100% in examined dogs. Lesions were restricted to the ocular surface and included bilateral conjunctivitis (100% of dogs); punctate, dendritic, or geographic ulcerative keratitis (26% of dogs); and non-ulcerative keratitis (19% of dogs). Conjunctival petechiae were detected in 22% of dogs. Punctate and dendritic corneal ulcers were frequently organized into discrete groups or linear arrangements. Non-ulcerative keratitis appeared clinically as a perilimbal ring of superficial corneal vascularization and leukocyte infiltration. CHV-1 was detected in ocular samples by polymerase chain reaction or virus isolation in all dogs sampled.
Conclusions  In susceptible populations of domestic dogs, CHV-1 may be associated with outbreaks of highly contagious ocular infection in the absence of concurrent overt systemic disease. This naturally-acquired outbreak of CHV-1 infection provides an opportunity to report the spectrum and prevalence of ocular lesions associated with primary ocular CHV-1 infection in dogs. Conjunctivitis was the most frequent ocular lesion detected. Ulcerative and non-ulcerative keratitis were less prevalent and of variable clinical appearance. Dendritic ulcerative keratitis, a classic and relatively specific ocular lesion associated with alphaherpesvirus infection, was detected in < 20% of dogs.     

Acremonium and trichosporon fungal keratoconjunctivitis in a Leopard Gecko (Eublepharis macularius)

A 6‐year‐old male leopard gecko (Eublepharis macularius) was presented with a 2‐year history of recurrent dysecdysis involving the ocular surface of both eyes. Ophthalmic examination revealed ocular surface desiccation and multifocal superficial ulcerative keratitis with patchy remnants of retained shed. Other abnormalities included stomatitis and mandibular and maxillary osteomyelitis. Topical and systemic antibiotic therapy, oral vitamin A, and improved husbandry conditions resolved the stomatitis and osteomyelitis but did not improve the ocular surface. Corneal cytology collected with a cytobrush revealed branching hyphae and budding yeast consistent with fungal keratitis. Fungal culture grew Acremonium sp. and Trichosporon sp. The addition of topical antifungal therapy improved the ocular surface health, but the patient was euthanized 7 weeks after initial presentation for persistent vomiting and dyspnea. Necropsy was declined. This case describes the first case of fungal keratitis caused by Acremonium sp. and Trichosporon sp. in a reptile.     

Feline corneal disease

The cornea is naturally transparent. Anything that interferes with the cornea's stromal architecture, contributes to blood vessel migration, increases corneal pigmentation, or predisposes to corneal edema, disrupts the corneas transparency and indicates corneal disease. The color, location, and shape and pattern of a corneal lesion can help in determining the underlying cause for the disease. Corneal disease is typically divided into congenital or acquired disorders. Congenital disorders, such as corneal dermoids are rare in cats, whereas acquired corneal disease associated with nonulcerative or ulcerative keratitis is common. Primary ocular disease, such as tear film instability, adenexal disease (medial canthal entropion, lagophthalmus, eyelid agenesis), and herpes keratitis are associated with the majority of acquired corneal disease in cats. Proliferative/eosinophilic keratitis, acute bullous keratopathy, and Florida keratopathy are common feline nonulcerative disorders. Nonprogressive ulcerative disease in cats, such as chronic corneal epithelial defects and corneal sequestration are more common than progressive corneal ulcerations.     

Osseous metaplasia in the conjunctiva of a horse presenting with recurrent ulcerative keratitis

A 13‐year‐old Thoroughbred gelding presented with a 6 month history of recurrent conjunctivitis, dacryocystitis and corneal ulceration affecting the left eye (OS). Treatment had included multiple topical antibiotic and anti‐inflammatory preparations, nasolacrimal system flushing and an injection of methylprednisolone acetate (MPA) (Depomedrone) ¹ administered subconjunctivally into the left lower eyelid. No mechanical cause for the ulcerative keratitis could be visualised but digital palpation revealed a firm linear structure in the central palpebral conjunctiva of the lower eyelid. An excisional biopsy was performed and histopathological examination revealed the lesion to be a region of osseous metaplasia. Following excision of the lesion, the corneal ulcer resolved and the eye remained disease free over a 4 year follow‐up period. A causal link between the osseous metaplasia and the recurrent ulcerative keratitis was therefore suspected. This report describes the management of this case and discusses the pathogenesis of osseous metaplasia and the use of subconjunctival corticosteroids.     

Superficial stromal keratitis in the dog

Superficial stromal keratitis or pannus is a syndrome of corneal, conjunctival and third eyelid inflammation. Superficial stromal keratitis mainly presents as a subepithelial corneal infiltration of vascular connective tissue, and usually arises from the lateral (temporal) limbal area. In some dogs perilimbal hyperaemia and third eyelid blepharitis can be present without corneal involvement. The most commonly affected breed of dog is the German Shepherd. Most cases of superficial stromal keratitis can be controlled with topical corticosteroids, and only rarely is cryosurgery or superficial keratectomy required to remove excessive pigment and or granulation tissue. The precise aetiology of SSK is unknown, but is likely to be multifactorial, with sunlight being a significant factor. Corneal lipidosis and keratoconjunctivitis sicca can occur secondary to superficial stromal keratitis.     

Bacterial corneal diseases in dogs and cats

Corneal diseases are very common in small animals. Corneal disease associated with bacterial agents is frequent in the dog and maybe less frequent in the cat. The medical history, important steps of the ophthalmic examination, and the ophthalmic diagnostic tests that are relevant in such corneal conditions are outlined. Bacterial corneal diseases in dogs and cats are most commonly considered in one of two categories--bacterial ulcerative keratitis and corneal abscesses. The clinical aspects of these two entities as well as the therapeutic strategies available for general practitioners and ophthalmologists are discussed. Ulcerative keratitis is frequent; it represents the most common ocular diseases in dogs and cats. Because some of these corneal ulcers can be very severe, progress rapidly, and therefore are sight threatening, the crucial steps of their diagnosis and management are stressed. The use of a magnification system, fluorescein dye, and corneal cytology and culture, if indicated, is necessary for diagnosis at an early stage of the disease. The treatment of bacterial ulcerative keratitis should eradicate the infection, reduce or stop the corneal destruction and support the corneal structures, control the uveal reaction and the pain associated with it, and minimize the scarring. The prognosis depends on the stage and the severity of the corneal ulceration, the etiology of the condition, and the therapeutic choice. A close follow-up of animals with corneal ulceration is highly recommended because corneal ulcers can progress rapidly.     

In vitro fluoroquinolone susceptibility of Pseudomonas aeruginosa isolates from dogs with ulcerative keratitis

OBJECTIVE: To determine the in vitro fluoroquinolone susceptibility profiles of Pseudomonas aeruginosa isolates from dogs with ulcerative keratitis. Animals-27 dogs with P. aeruginosa-associated ulcerative keratitis. PROCEDURES: P. aeruginosa isolates from dogs with ulcerative keratitis were collected during a 3-year period. Isolates were tested by use of the disk diffusion method for their susceptibility to 7 fluoroquinolones that are available as commercial ophthalmic preparations. The antimicrobials included second- (ciprofloxacin, ofloxacin, norfloxacin, and lomefloxacin), third- (levofloxacin), and fourth-generation (gatifloxacin and moxifloxacin) fluoroquinolones. Isolates were designated as susceptible, intermediate, or resistant to the various antimicrobials. The percentage of susceptible isolates was compared among individual fluoroquinolones and among fluoroquinolone generations. RESULTS: None of the dogs had received topical or systemic fluoroquinolone treatment prior to referral. Twenty-seven P. aeruginosa isolates were collected during the study period. In vitro, bacterial resistance to the tested fluoroquinolones was infrequently identified (24/ 27 isolates were susceptible to all fluoroquinolones evaluated); susceptibility percentages ranged from 88.9% to 100% for individual antimicrobials. There were no significant differences among isolate susceptibilities to the individual antimicrobials or among generations of fluoroquinolones. CONCLUSIONS AND CLINICAL RELEVANCE: On the basis of these in vitro data, none of the 7 evaluated fluoroquinolones (individually or collectively by generation) appeared to offer a clinically important advantage in the treatment of P. aeruginosa-associated ulcerative keratitis in dogs. Among the P. aeruginosa isolates collected from dogs with ulcerative keratitis in this study, the likelihood of susceptibility to the fluoroquinolones evaluated was high.     

A novel herpesvirus associated with chronic superficial keratitis and proliferative conjunctivitis in a great horned owl (Bubo virginianus)

An adult great‐horned owl (Bubo virginianus; GHOW) presented with a history of recurrent corneal ulceration of the right eye (OD). Findings included ulcerative superficial keratitis, proliferative conjunctivitis, and iris pigmentary changes. The ulcer was initially nonresponsive to medical therapy, but showed rapid and appropriate healing following diamond burr debridement. Proliferative conjunctivitis markedly improved following topical antiviral therapy with cidofovir 1%, interferon alpha 2B ophthalmic solutions, and oral l ‐lysine. Histopathologic evaluation of a conjunctival biopsy revealed epithelial features suspicious for viral cytopathic changes and intranuclear structures suspicious for viral inclusions, suggestive of a possible viral‐induced papillomatous conjunctivitis. A novel alphaherpesvirus, referred to as Strigid Herpesvirus 1 (StrHV1), was identified using PCR and gene sequencing. This case represents a new clinical manifestation of a previously unreported herpesvirus in the GHOW. Identification of the herpes virus was critical to administration of appropriate therapy and resolution of the conjunctivitis, and corneal epithelial debridement promoted resolution of the chronic corneal epithelial defect.     

Prevalence of equine ulcerative keratomycosis in Colorado and association of environmental factors: A retrospective and descriptive study (2002–2017)

Equine ulcerative keratomycosis is relatively commonly presented to teaching hospitals in North America, with a prevalence from 24 to 86%. Horses in Colorado may have lower risk due to the dry mountain climate, but data are lacking. This study aimed to determine the prevalence of ulcerative keratomycosis amongst horses with ulcerative keratitis presented to Colorado State University Veterinary Teaching Hospital (CSU-VTH) ophthalmology service and to evaluate environmental factors (season, temperature, humidity, wind speed and elevation) associated with ulcerative keratomycosis in Colorado. A database search identified horses with ulcerative keratitis presented to the ophthalmology service at CSU-VTH from January 2002 to August 2017. Sixty-one horses met the inclusion criteria of a corneal cytology and/or culture or histopathology at the time of diagnosis; cases lacking that were excluded. Environmental factors at the boarding sites, including season, temperature, humidity, wind speed and elevation and clinical outcomes for fungal cases, were recorded. Prevalence of fungal infection amongst equine ulcerative keratitis was 16.4% (10/61), suggesting that CSU-VTH has considerably fewer ulcerative keratomycosis cases than other veterinary teaching hospitals in North America. Spring (50%, 5/10) and fall (40%, 4/10) had the highest prevalence of fungal ulcerative keratitis in Colorado. Only one case was reported in summer (10%, 1/10); no horses were positive (0%, 0/10) in winter. Only wind speed seemed to influence the development of ulcerative keratomycosis with higher wind speeds associated with greater rates of fungal involvement (P = 0.047). Other environmental factors did not show a detectable association (all P-values >0.05). Outcomes were variable. It was concluded that horses from the area of CSU-VTH appear to be at lower risk for ulcerative keratomycosis than from the areas around other North American veterinary teaching hospitals that have reported data. Most horses with keratomycosis in this area present in the spring and fall.     

Bacterial isolates and antimicrobial susceptibilities in equine bacterial ulcerative keratitis (1993--2004)

REASONS FOR PERFORMING STUDY: Bacterial ulcerative keratitis is a common and often vision-threatening problem in horses. Emerging bacterial resistance to commonly used topical antibiotics has been demonstrated. Previous antibiotic use may alter the antimicrobial susceptibility of bacterial isolates. OBJECTIVES: To document aerobic bacterial isolates and associated bacterial susceptibilities from horses with ulcerative keratitis treated at the University of Tennessee between January 1993 and May 2004 and determine whether prior antibiotic therapy affected antimicrobial susceptibility of the isolates. METHODS: Medical records from horses with ulcerative keratitis and positive aerobic bacterial cultures and antimicrobial susceptibility were evaluated. Clinical history regarding antibiotic therapy prior to culture was documented. RESULTS: Fifty-one aerobic bacterial isolates from 43 horses were identified. Streptococcus equi subspecies zooepidemicus was the most commonly isolated organism, accounting for 33.3% of all isolates, followed by Pseudomonas aeruginosa (11.8%), Staphylococcus spp. (11.8%) and Gram-negative nonfermenting rods (7.8 %). No resistance was noted amongst S. equi ssp. zooepidemicus to cephalothin, chloramphenicol or ciprofloxacin. Only 64 % of S. equi ssp. zooepidemicus isolates were sensitive to bacitracin. No resistance was noted among P. aeruginosa to gentamicin, tobramycin or ciprofloxacin. Antibiotic therapy with neomycin-polymixin B-bacitracin prior to presentation and culture was documented in 11/17 horses in which S. equi ssp. zooepidemicus was isolated and in 4/6 horses in which P. aeruginosa was isolated. Three horses received topical corticosteroids prior to culture, of which 2 had polymicrobial infections. CONCLUSIONS: S. equi ssp. zooepidemicus and P. aeruginosa were the most frequently isolated bacterial organisms in equine ulcerative keratitis. No significant trends in aminoglycoside or fluoroquinolone resistance were noted among these organisms. However, the resistance of S. equi ssp. zooepidemicus to bacitracin with common use of this antibiotic suggests that previous antibiotic therapy probably affects antimicrobial resistance. POTENTIAL RELEVANCE: Therapy prior to culture may play an important role in antimicrobial susceptibility of corneal bacterial isolates. Corticosteroid use may increase the risk of polymicrobial infections of corneal ulcers, leading to a worse prognosis. Although significant fluoroquinolone resistance has not been documented in the veterinary literature, these antimicrobials should be reserved for known infected corneal ulcers and not used for prophylaxis. Empirical antibiotic therapy should not only be guided by clinical signs, but also take into consideration previous antimicrobial and corticosteroid therapy.     

Efficacy of two chondroitin sulfate ophthalmic solutions in the therapy of spontaneous chronic corneal epithelial defects and ulcerative keratitis associated with bullous keratopathy in dogs

OBJECTIVE: To determine the efficacy of two antimicrobial-chondroitin sulfate ophthalmic solutions in the therapy of spontaneous chronic corneal epithelial defects (SCCED) and ulcerative keratitis associated with bullous keratopathy in dogs. ANIMALS STUDIED: Eighty dogs with SCCED and 14 dogs with ulcerative keratitis associated with bullous keratopathy. PROCEDURE: Following manual debridement of nonadherent epithelium, dogs were treated topically with a chondroitin sulfate ophthalmic solution containing either tobramycin or ciprofloxacin. Patients were re-evaluated at 2-week intervals for 4 weeks. RESULTS: After 2 weeks of treatment, 53.6% of eyes with SCCED and 17.6% of eyes with ulcerative keratitis associated with bullous keratopathy had healed. After 4 weeks of treatment, 81.0% of eyes with SCCED and 23.5% of eyes with ulcerative keratitis associated with bullous keratopathy had healed. There were no statistically significant differences in healing percentages between the tobramycin-chondroitin sulfate solution treatment groups and the ciprofloxacin-chondroitin sulfate solution treatment groups. Two dogs with SCCED, one treated with the tobramycin-chondroitin sulfate solution and the other treated with the ciprofloxacin-chondroitin sulfate solution, developed sterile corneal stromal abscesses during the study. CONCLUSIONS: Topical therapy with an antimicrobial-chondroitin sulfate ophthalmic solution combined with manual debridement of nonadherent epithelium compares favorably with other published medical and surgical therapies for SCCED; however, these compounds are only equivocally more effective than therapy with manual debridement alone. These solutions appear to be ineffective in the treatment of ulcerative keratitis associated with bullous keratopathy. The significance of the two cases of corneal stromal abscessation is unknown at this time and warrants further investigation.     

Immune-mediated canine and feline keratitis.

Although the normal cornea is devoid of vasculature and lymphatics, there are still several immune-mediated corneal conditions that can occur in dogs and cats. An overview of corneal immunology is presented. Diseases of dogs, including chronic superficial keratitis, superficial punctate keratitis, and canine adenovirus endotheliitis, as well as feline diseases, including eosinophilic keratitis and herpesvirus-related conditions, are discussed.     

Successful treatment of distichiasis in a cat using transconjunctival electrocautery

A 2-year-old male castrated Domestic Short-haired cat presented to the Ophthalmology Service at the Matthew J. Ryan Veterinary Hospital at the University of Pennsylvania for evaluation of chronic bilateral ocular discharge and blepharospasm. Initial ophthalmic examination revealed severe conjunctivitis and keratitis and the presence of upper eyelid distichiae bilaterally. Initial therapy for suspected feline herpesviral infection provided moderate, but not complete, resolution of the clinical signs. Over the subsequent year, the cat suffered from recurrent, severe, ulcerative keratitis in both eyes despite appropriate medical therapy. Approximately 13 months after the initial presentation, the distichiae were surgically removed using transconjunctival electrocautery, which resulted in complete resolution of the clinical signs. This report documents bilateral distichiasis in a cat, a condition that is considered rare in this species.     

Methicillin‐resistant Staphylococcus aureus keratitis in a dog

The purpose of this study is to report a case of methicillin‐resistant Staphylococcus aureus (MRSA) keratitis in a dog. A 7‐year‐old intact male American cocker spaniel that had undergone removal of a nictitating gland was referred for severe ulcerative keratitis. Slit‐lamp examination showed swelling of the eyelid, mucopurulent discharge, conjunctival injection and chemosis, diffuse corneal edema and opacity, and a deep ulcer in central cornea. Gram staining of discharge from the eye demonstrated Gram‐positive cocci. Despite topical ofloxacin, oxytetracycline and polymyxin B ophthalmic solution and intravenous cefazolin, there was no improvement. Cultures revealed MRSA that was sensitive only to chloramphenicol, vancomycin, lincomycin, and clindamycin. The antibiotic regimen was changed to topical and systemic chloramphenicol. After 9 days of treatment, although inflammation started to be resolved, the dog developed nonregenerative anemia. The antimicrobial regimen was changed again to topical and systemic vancomycin. Inflammation continued to improve over the next week. MRSA should be considered a potential organism in infectious keratitis, especially when general antibiotics are not effective. Although topical and systemic chloramphenicol and/or vancomycin are effective for treating MRSA keratitis, vancomycin should only be used when culture and susceptibility results indicate it is appropriate and no other options are available. To our knowledge, this is the first detailed case report of MRSA keratitis in a dog.     

Use of conjunctival pedicle grafts in the management of feline keratitis nigrum

Feline keratitis nigrum (necrosis, sequestrum or sequestration) usually presents as a black plaque in the axial or paraxial cornea. Most cats can be treated by excision of the lesion and covering the defect with a third eyelid flap. This technique did not provide satisfactory results in some cases. This paper describes microsurgery using conjunctival pedicle grafting following keratectomy to provide a one step technique to manage recurrent feline keratitis nigrum, feline keratitis nigrum with full thickness lesions of corneal stroma and eyes also affected with keratoconjunctivitis sicca.     

Silicone allergy associated with intraocular silicone ball prosthesis in a dog

A 13-year-old, male Pomeranian dog was presented for scleral rupture with intraocular hemorrhage and retinal detachment in the right eye. After intrascleral silicone ball prosthesis, recurrent swelling and granulomatous blepharitis were observed for 140 d and finally melting keratitis developed. Although an intraorbital prosthesis was implanted, recurrent, serious, erosive, and ulcerative blepharitis developed with high plasma C-reactive protein concentrations. Since the blepharitis could not be controlled, the silicone ball was removed and the affected orbit was debrided. The blepharitis resolved rapidly, and the orbit healed routinely. Positive allergic reactions to silicone were discovered through a patch test.Key clinical message:To the authors’ knowledge, this is the first report on silicone allergy in a dog with positive allergic reactions to silicone in the patch test.     

Nutritionally variant streptococci associated with corneal ulcers in horses: 35 cases (1982-1988)

Nutritionally variant streptococci (NVS) are nutritionally deficient viridans streptococci that require pyridoxal for growth. Although NVS are pathogenic in human beings, they have not been considered to be pathogenic in domestic animals. In 1982 and 1983, 24 isolates of NVS were recovered from horses with ulcerative keratitis. A retrospective study was done to determine the incidence of NVS in horses with corneal disease. The medical records of 249 horses (259 eyes) examined for clinical signs of corneal disease were reviewed. Nutritionally variant streptococci were isolated from approximately 13.5% of horses with ulcerative keratitis.     

The treatment of corneal ulcers

The anatomy of the cornea and the method of assessing corneal damage are described. The many causes of ulcerative keratitis are stated. The general principles of treatment are set down. Particular treatments are then described according to the causative agent and to the type of ulcer. In a paper of this length it will not be possible to consider the specific treatment of each and every type of corneal ulceration that occurs in the dog. The causes of ulcerative keratitis are many and this paper will consider the general principles involved and, in particular, some of the more common varieties of corneal ulcer. Résumé. On a décrit l'anantomie de la cornée et la méthode pour évaluer le dommage cornéen. Les nombreuses causes de la kératite à hypopyon sont réglées. Les principes généraux du traitement sont posés. Puis les traitements particuliers sont décrits selon l'agent pathogène et le type de l'ulcère. Zusammenfassung . Die Anatomie von der Hornhaut und die Methode, die kornealen Schäden zu abzuschätzen, werden beschrieben. Viele Ursachen von Hypopyonkeratitis werden angegeben. Die allgemeinen Grundsätze der Behandlung werden aufgeschoben. Dann werden besondere Behandlungen nach dem verursachenden Mittel und nach dem Typ vom Geschwür beschrieben.