ABSTRACT
The case of an equine with nodular lymphocytic conjunctivitis is described. A 14-year-old crossbred mare was seen presenting with development of a mass in the nasal angle of the right eye, behind the third eyelid. The tutor reported slow growth over 4 years, always accompanied by epiphora, and that no treatment had been performed prior to consultation. The histopathological and immunohistochemical results found a nodular, subepithelial structure, composed predominantly of densely packed small lymphocytes. Through the exams, associated with studies with monoclonal anti B lymphocyte antibodies and polyclonal anti T lymphocyte antibodies, the diagnosis of nodular lymphocytic conjunctivitis was reached. Only clinical pharmacological treatment was chosen, based on the use of topical and intralesional hydrocortisone acetate. After one month of treatment the mass completely disappeared without sequelae.
Descreve-se o caso de um equino com conjuntivite linfocítica nodular. Uma égua, mestiça, de 14 anos, foi atendida apresentando desenvolvimento de uma massa no ângulo nasal do olho direito, atrás da terceira pálpebra. O tutor relatou um crescimento lento durante 4 anos, sempre acompanhado de epífora, para o qual não foi realizado tratamento prévio à consulta. Os resultados histopatológico e imuno-histoquímico constataram uma estrutura nodular e subepitelial, composta predominantemente por linfocitos pequenos densamente agrupados. Por meio dos exames, associados a estudos com anticorpos monoclonais antilinfocitos B e anticorpos policlonais antilinfocitos T, chegou-se ao diagnóstico de conjuntivite linfocítica nodular. Optou-se apenas pelo tratamento clínico farmacológico, baseando-se na utilização de acetato de hidrocortisona tópica e intralesional. Após um mês de tratamento, a massa involuiu por completo, sem deixar sequelas.
Subject(s)
Animals , Hydrocortisone/administration & dosage , Lymphocytes , Conjunctivitis/veterinary , Horses/virology , Immunohistochemistry/veterinaryABSTRACT
Oxidative stress is a risk factor for eye diseases. Free radicals elicited during the inflammatory process often lead to oxidative damage of lipids (lipid peroxidation). The retina is highly vulnerable because of its high content of polyunsaturated fatty acids (PUFAs). The aim of this study was to investigate in vitro the effect of alpha-tocopherol on the Fe(2+)-ascorbate induced lipid peroxidation in the canine retina. Lipid peroxidation of retinal homogenates was carried out with and without the addition of alpha-tocopherol and monitored both by chemiluminescence and production of thiobarbituric acid reactive substances (TBARS). Total chemiluminescence counts per minute was lower in those homogenates pre-incubated with alpha-tocopherol. Thus, with 1 micromol alpha-tocopherol/mg of protein, 100% inhibition of chemiluminescence and a decrease of TBARS content from 20.46+/-0.85 to 2.62+/-2.77 nmol/mg protein were observed. Simultaneously, changes produced by oxidative stress were noted in the fatty acid composition of retinal lipids. Docosahexaenoic acid was decreased from 14.33+/-2.32% to 1.84+/-0.14% after peroxidation, but this fatty acid remained unaltered in the presence of 1 micromol alpha-tocopherol. These results show that under these experimental conditions, alpha-tocopherol may act as anti-oxidant protecting retinal membranes from deleterious effects. Further studies are required to assess its use in free radical generating conditions affecting the canine retina.