Ocular and periocular manifestations of leishmaniasis in dogs: 105 cases (1993-1998)

The purpose of this retrospective study was to determine the prevalence, type, and prognosis of ocular lesions associated with leishmaniasis in dogs. One hundred and five dogs (24.4% of all cases of leishmaniasis diagnosed during the study period) had ocular or periocular leishmaniasis, and 16 dogs (15.2% of ocular cases) had only ocular lesions and systemic signs were not apparent. Anterior uveitis was the most common manifestation and other prevalent findings included blepharitis and keratoconjunctivitis. Several distinct variations of eyelid lesions were seen including a dry dermatitis with alopecia, diffuse blepharedema, cutaneous ulceration, and discrete nodular granuloma formation. In some cases with keratoconjunctivitis, corneal lesions clinically resembled nodular granulomatous episclerokeratitis. Twenty-seven of the 34 cases with ocular lesions had improvement in signs following systemic antiprotozoal and topical anti-inflammatory therapy, although many cases with anterior uveitis required long-term topical therapy. Response of ocular signs correlated highly with overall, systemic response to therapy. Ophthalmic manifestations of systemic leishmaniasis are common in the dog, and this disease should be considered in the differential diagnosis of most adnexal and anterior segment ocular inflammatory lesions in dogs in endemic areas.     

Three cases of feline ocular coccidioidomycosis: presentation,clinical features,diagnosis, and treatment

Objective To describe clinical and diagnostic features of ocular coccidioidomycosis in cats and the response to fluconazole and anti‐inflammatory therapy. Animals studied Three cats with naturally acquired coccidioidomycosis. Procedure Cats were treated with topical or systemic corticosteroids and systemic fluconazole, an antifungal of unproven efficacy against feline ocular coccidioidomycosis. Results Two cats presented for periocular swellings, either subpalpebral or periorbital, with systemic signs including weight loss, unkempt hair coat, and lethargy. One cat presented for apparent blindness with no systemic signs. Clinical ophthalmologic abnormalities were bilateral in each cat and included hyperemic, conjunctival masses, fluid‐filled periorbital swellings, granulomatous chorioretinitis, nonrhegmatogenous retinal detachments, and anterior uveitis. Cats were diagnosed with coccidioidomycosis using a combination of clinical findings, serology and, in two cases, visualization of Coccidioides spherules by either aspiration cytology or biopsy. Active anterior uveitis and periocular swelling were resolved in all cats during treatment. Chorioretinal granulomas, although persistent, significantly decreased in size. Conclusions Coccidioidomycosis should be considered as a differential diagnosis for cats with a travel history to the southwestern United States that demonstrate periocular swelling, anterior uveitis, or granulomatous chorioretinitis, with or without evidence of systemic disease. Aspiration cytology or biopsy of suspicious conjunctival or skin lesions, if present, may aid in diagnosis. A combination of corticosteroids and fluconazole may be effective in treating ocular coccidioidomycosis, although chorioretinal granulomas may persist and long‐term fluconazole therapy may be necessary.     

Mycotic endophthalmitis in a dog caused by Candida albicans

A case of mycotic endophthalmitis in the dog caused by Candida albicans is presented. The 3-year-old dog had a history of bloody diarrhea 3 months previously. The dog presented with acute signs of unilateral panuveitis. Aqueocentesis, vitreocentesis, and routine blood tests were performed but did not contribute to the diagnosis. The posterior segment could not be visualized because of flare and fibrin. On day 7 ultrasonography showed retinal separation which progressed to vitreous compartmentalization and abscessation by day 14. Three weeks after onset, glaucoma developed and enucleation was performed. Histology revealed the yeast Candida to be the causative agent. Post-enucleation serum Candida antibody titer was 1 : 640 (human threshold 1 : 120), as determined by agglutination test. A relapse of enteric signs 3 months later led to the diagnosis of chronic lymphocytic enteritis. An hematogenous route of infection is suspected.     

Effect of vaccination against leptospirosis on the frequency, days to recurrence and progression of disease in horses with equine recurrent uveitis

OBJECTIVE: To evaluate the effect of vaccination against leptospirosis on frequency and days to recurrence of uveitis and progression of disease in horses with equine recurrent uveitis (ERU). ANIMALS: Forty-one horses with ERU. PROCEDURE: Horses were randomly assigned to experimental (vaccinated) or control groups. Vaccine containing six serovars of Leptospira or placebo was administered, an ophthalmic examination performed and blood samples drawn on days 0, 28, 180 and 365. Antibody titers were measured against each serovar. Recurrence of uveitis was verified by ophthalmic examination. Results of the initial and final ophthalmic examinations were compared and progression of disease defined as an increase in extent of synechiae, or development of new or progression of an existing cataract. RESULTS: Vaccination increased the average geometric mean serum antibody titer from 225 on day 0, to 4077 and 593 on days 28 and 180, respectively. After the second vaccination, days to first recurrence was significantly longer (median 126 days; range 24-231 days) when compared with controls (median 86 days; range 14-192 days, P=0.04). Recurrence of ERU was observed among 7/20 (35%) vaccinated horses and 12/21 (57%) controls; however, this difference was not statistically significant (P=0.061, OR 0.25, 95% CI 0.06, 1.07). More horses in the experimental group 13/20 (65%) experienced progression of disease when compared with controls 12/21(57%); however, this difference was statistically nonsignificant (P=0.35). CONCLUSIONS: Vaccine significantly increased days to recurrence, but failed to slow the progression of disease. These data do not support the use of vaccination against leptospirosis as adjunct therapy for the routine treatment of horses with ERU.     

Deep lamellar endothelial keratoplasty in 10 horses

Objective  To describe and evaluate a surgical technique utilized for the therapy of deep corneal stromal abscesses (DSA) in horses. The DSA is excised and replaced with a partial thickness corneal lamellar allograft.
Methods  A retrospective clinical study describing the indications for the surgical technique utilized and the outcomes of this procedure in 10 eyes of 10 horses.
Results  Each affected eye had a discrete DSA within the posterior stroma. An initial partial thickness semicircular corneal incision was made at the limbus, followed by anterior stromal lamellar dissection over the lesion. After excision of the DSA and replacement with a larger diameter split-thickness donor button, the anterior stroma was replaced into its original position and the initial corneal incision was repaired. All of the animals that underwent deep lamellar endothelial keratoplasty (DLEK) procedure healed appropriately and with subjectively less postoperative scarring and complications than previously described surgical approaches to DSA.
Conclusions  This procedure is an effective technique for surgical removal of DSA in horses and, in most cases, results in a visual and cosmetically acceptable globe. The advantages of this technique compared to other surgical approaches to DSA are the peripheral location of the incision, shortened anesthesia times, the resultant minimal scarring and shorter healing times associated with DLEK.     

Bartonellosis in cats: a role in uveitis?

Bartonellosis has been widely studied in human and veterinary medicine over the past two decades. Despite this fact, it remains an enigmatic disease in many ways. The causative bacteria, Bartonella spp, are transmitted to cats by fleas and thus the prevalence in cat populations, particularly in temperate climates, is high. Most cats, whether infected naturally or experimentally, remain asymptomatic. Thus, correlating the presence of the organism to clinical disease, including uveitis, in cats has been difficult. This review summarizes what is known of the transmission and pathogenesis of Bartonella spp in cats, the possible role of the organism in feline ocular disease, as well methods of diagnosis and treatment.     

Post mortem magnetic resonance imaging of multiple congenital ocular anomalies in a Comtois mare

Multiple congenital ocular anomalies syndrome consists of several abnormalities mainly localised to the anterior segment of the eye. This condition, comprising iridal or ciliary cysts with or without iridal hypoplasia, an excessively protruding cornea (‘cornea globosa’), miotic pupils, retinal dysplasia, cataract, and other lesions, has been reported in several breeds and is strongly related to the silver coat colour, as a result of a dominant mutant allele at the PMEL17 locus. This report describes the macroscopic, ultrasonographic, histological and magnetic resonance imaging findings of the ocular abnormalities in a Comtois mare with multiple congenital ocular anomalies syndrome.     

Acute Effects of Ivabradine on Dynamic Obstruction of the Left Ventricular Outflow Tract in Cats with Preclinical Hypertrophic Cardiomyopathy

Background

Ivabradine is a negative chronotropic drug with minimal effects on central hemodynamics. Its effect on dynamic obstruction of the left ventricular outflow tract (LVOT) in cats with hypertrophic cardiomyopathy (HCM) remains unknown.

Hypothesis/Objectives

Ivabradine reduces dynamic obstruction of the LVOT in cats with HCM.

Animals

Twenty‐eight client‐owned cats with preclinical HCM and dynamic LVOT obstruction.

Methods

Randomized, double‐blind, active‐control single dose study. Cats received a single dose of either ivabradine (0.3 mg/kg PO) or atenolol (2 mg/kg PO). Heart rate, echocardiographic variables, and systolic blood pressure (SBP) were recorded before and 3 hours after drug administration. Statistical comparisons were made using ANCOVA.

Results

Peak velocity in the LVOT was significantly decreased compared to baseline for both drugs; however, the effect was more prominent with atenolol (mean reduction 2.53 m/s; 95% CI 2.07–3.13 m/s) compared to ivabradine (mean reduction 0.32 m/s; 95% CI −0.04 to 0.71 m/s; P < .0001). Echocardiographic indices of systolic function were largely unchanged by ivabradine, but significantly reduced by atenolol.

Conclusions and Clinical Importance

A single dose of ivabradine decreases dynamic LVOT obstruction in cats with HCM, but the clinical effect is negligible and inferior compared to that achieved by atenolol.