RESUMO
In many parts of the world, parasitic infections of the eye are a major cause of blindness. The parasites Toxocara canis, Onchocerca volvulus, Taenia solium, Ancylostoma caninum, and Cysticercus celulosae all have been responsible for blinding ocular infections. The nematodes T. canis and Toxocara cati are parasitic roundworms that infect dogs (toxocarosis), other canidae, and cats. Ocular toxocariasis is an uncommon worldwide infection caused by the nematode larvae of T. canis, commonly found in dogs. Human transmission is usually via geophagia, the ingestion of food contaminated with Toxocara eggs, or contact with infected puppies, often resulting in devastating ocular or systemic effects. Ocular toxocariasis is typically a monocular disease of young children, and its clinical findings include posterior and peripheral retinochoroiditis, optic papillitis, and endophthalmitis. The inflammatory response created by ocular involvement may result in epiretinal membrane formation, traction retinal detachment, and combined traction-rhegmatogenous retinal detachment. Diffuse unilateral subacute neuroretinitis is another ocular parasitic infection that usually results in severe visual loss. Evidence suggests that diffuse unilateral subacute neuroretinitis is caused by a solitary unidentified nematode of two different sizes, but to date, only a small number of nematodes have been recovered from eyes affected with the infection. Diffuse unilateral subacute neuroretinitis occasionally can affect the fellow eye.
Assuntos
Infecções Oculares Parasitárias/parasitologia , Neurite Óptica/parasitologia , Retinite/parasitologia , Toxocaríase/parasitologia , Antiprotozoários/uso terapêutico , Infecções Oculares Parasitárias/diagnóstico , Infecções Oculares Parasitárias/tratamento farmacológico , Humanos , Neurite Óptica/diagnóstico , Neurite Óptica/tratamento farmacológico , Retinite/diagnóstico , Retinite/tratamento farmacológico , Toxocaríase/diagnóstico , Toxocaríase/tratamento farmacológicoRESUMO
Os autores apresentam um caso de neurorretinite subaguda difusa unilateral (D.U.S.N) confirmada com a identificaçäo da larva em uma criança de 6 anos associada a quadro de larva migrans cutânea, bem como a análise de outros sete casos de D.U.S.N. e sua associaçäo sorológica àtoxocaríase e antecedentes de larva migrans cutânea. Este é o primeiro caso descrito na literatura de D.U.S.N. concomitante a larva migrans cutânea na fase ativa.
Assuntos
Humanos , Masculino , Criança , Ancilostomíase/complicações , Ancylostoma , Infecções Oculares Parasitárias/parasitologia , Neurite Óptica/parasitologia , Retinite , Brasil , Infecções Oculares Parasitárias/diagnóstico , Larva Migrans , Neurite Óptica/diagnóstico , RetiniteRESUMO
OBJECTIVE: To describe the first patient with documented evidence of diffuse unilateral subacute neuroretinitis (DUSN) in both eyes. METHODS: A 10-year-old healthy Brazilian girl was first seen with signs of late-stage DUSN in both eyes. A careful search for a nematode was performed in each eye. RESULTS: A motile 550- to 660-microm nematode was found in the inferotemporal retina of the left eye. A similar-sized motile nematode was found in the superotemporal retina of the right eye. Both nematodes were treated with argon green laser applications with bilateral improvement of visual function. CONCLUSION: Although most patients with DUSN do not develop the disease in the fellow eye, this case demonstrates that DUSN can occasionally affect both eyes.
Assuntos
Infecções Oculares Parasitárias , Infecções por Nematoides , Neurite Óptica/parasitologia , Retina/parasitologia , Retinite/parasitologia , Doença Aguda , Animais , Anticorpos Anti-Helmínticos/análise , Ascaris lumbricoides/isolamento & purificação , Criança , Ensaio de Imunoadsorção Enzimática , Infecções Oculares Parasitárias/diagnóstico , Infecções Oculares Parasitárias/parasitologia , Infecções Oculares Parasitárias/cirurgia , Fezes/parasitologia , Feminino , Humanos , Terapia a Laser , Infecções por Nematoides/diagnóstico , Infecções por Nematoides/parasitologia , Infecções por Nematoides/cirurgia , Neurite Óptica/diagnóstico , Neurite Óptica/cirurgia , Retina/patologia , Retina/cirurgia , Retinite/diagnóstico , Retinite/cirurgia , Toxocara canis/imunologia , Acuidade Visual , Campos VisuaisAssuntos
Infecções Oculares Parasitárias , Infecções por Nematoides , Neurite Óptica/parasitologia , Retinite/parasitologia , Doença Aguda , Adolescente , Brasil , Infecções Oculares Parasitárias/parasitologia , Infecções Oculares Parasitárias/patologia , Infecções Oculares Parasitárias/cirurgia , Humanos , Fotocoagulação a Laser , Masculino , Infecções por Nematoides/parasitologia , Infecções por Nematoides/patologia , Infecções por Nematoides/cirurgia , Neurite Óptica/patologia , Neurite Óptica/cirurgia , Retina/parasitologia , Retina/patologia , Retina/cirurgia , Retinite/patologia , Retinite/cirurgia , Acuidade VisualRESUMO
PURPOSE: To evaluate the efficacy of ivermectin and thiabendazole in confirmed cases of diffuse unilateral subacute neuroretinitis. METHODS: Two patients with diffuse unilateral subacute neuroretinitis were treated with anthelminthic drugs. The first patient was treated with ivermectin and the second, with thiabendazole. RESULTS: The worms were still mobile after treatment with ivermectin or thiabendazole. With the application of photocoagulation, the organisms were destroyed, and the patients' vision improved. CONCLUSION: In these two patients, ivermectin and thiabendazole were not effective in treating confirmed diffuse unilateral subacute neuroretinitis.
Assuntos
Anti-Helmínticos/uso terapêutico , Infecções Oculares Parasitárias/terapia , Fotocoagulação a Laser , Neurite Óptica/terapia , Infecções por Protozoários/terapia , Retinite/terapia , Doença Aguda , Adolescente , Adulto , Infecções Oculares Parasitárias/parasitologia , Infecções Oculares Parasitárias/patologia , Feminino , Fundo de Olho , Humanos , Ivermectina/uso terapêutico , Masculino , Neurite Óptica/parasitologia , Neurite Óptica/patologia , Infecções por Protozoários/parasitologia , Infecções por Protozoários/patologia , Retina/parasitologia , Retinite/parasitologia , Retinite/patologia , Tiabendazol/uso terapêutico , Acuidade VisualRESUMO
BACKGROUND: The precise identification of nematodes which cause diffuse unilateral subacute neuroretinitis (DUSN) has been unsuccessful. Shape and size are useful in the initial stages of identification, but histopathologic examination usually is necessary for accurate classification. Intact nematodes recovered from patients with DUSN have been mentioned scarcely in the literature. The authors report the first case of DUSN in which a viable nematode was removed successfully via a transvitreal surgical approach and recovered for parasitologic study. METHODS: Bimanual pars plana vitrectomy was performed in a 9-year-old Brazilian boy with typical DUSN in its late stage. During surgery, a motile subretinal nematode was confirmed temporal to the macular area. A retinotomy was created adjacent to the nematode. The subretinal material then was aspirated with a 20-gauge soft-tip needle, and parasitologic examination was performed. RESULTS: Based on length (630 m x 10(-6)) and width (30 m x 10(-6)) of the nematode and other features such as a small buccal capsule, an esophagus one third of body length, and tapered tail, a morphologic identification of the nematode was made as a third-stage Toxocara larva. Histopathologic examination could not be performed for confirmation because of subsequent deterioration of the specimen. CONCLUSIONS: Although direct laser photocoagulation of the nematode is the treatment of choice for DUSN, surgical transvitreal removal of the nematode may be indicated in selected cases. This method for treatment allows removal of the nematode for parasitologic identification.