Non-Paraneoplastic Autoimmune Retinopathy: The First Case Report in Korea

Autoimmune retinopathy (AIR) is an immune-mediated retinopathy, resulting from an immunologic process caused by the aberrant recognition of retinal antigens as autoantigens. The diagnosis of AIR involves the detection of antiretinal antibodies with concurrent clinical and electrophysiological evidence of retinopathy. A 40-year-old patient presented with progressive loss of bilateral vision over several months. A fundus examination was unremarkable. Spectral domain optical coherence tomography revealed a blurred photoreceptor ellipsoid zone at the subfoveal region in both eyes with more prominent disruption in the left eye. Full-field electroretinography (ERG) showed relatively normal rod and cone responses in the right eye, and decreased photopic bwaves with minimal attenuation of a-waves in the left eye. Multifocal ERG demonstrated slightly reduced amplitude of the inner segment ring in the right eye and decreased amplitudes and delayed latencies of all modalities in the left eye. The patient was suspected to have AIR and it was supported by positive Western blots for 23-kDa protein, enolase (46-kDa), aldolase (40-kDa), 62-kDa and 78-kDa proteins and by immunohistochemical staining of human retinal bipolar and ganglion cells. Despite the immunosuppressive treatment, the destruction of the retinal photoreceptors progressed, and immunosuppressive interventions produced very little visual improvement. We report on what is, to the best of our knowledge, the very first case of serologically confirmed nonparaneoplastic AIR in Korea.

Increased frequency of anti-retina antibodies in asymptomatic patients with chronic t. gondii infection

PURPOSE: To search for anti-retina antibodies that serve as markers for eye disease in uveitis. MATERIALS AND METHODS: Stored sera from patients with uveitis, ocular toxoplasmosis (n = 30) and non-infectious, immune-mediated uveitis (n = 50) and from asymptomatic individuals who were positive (n = 250) and negative (n = 250) for anti-Toxoplasma antibodies were tested. Serum anti-retina IgG was detected by an optimized ELISA using a solid-phase whole human retina extract, bovine S-antigen or interphotoreceptor retinoid-binding protein. RESULTS: Uveitis patients showed a higher mean reactivity to whole human retina extract, interphotoreceptor retinoid-binding protein and S-antigen in comparison to the asymptomatic population. These findings were independent of the uveitis origin and allowed the determination of the lower anti-retina antibody cut-off for the three antigens. Asymptomatic anti-Toxoplasma serum-positive individuals showed a higher frequency of antihuman whole retina extract antibodies in comparison to asymptomatic anti-Toxoplasma serum-negative patients. The bovine S-antigen and interphotoreceptor retinoid-binding protein ELISAs also showed a higher mean reactivity in the uveitis groups compared to the asymptomatic group, but the observed reactivities were lower and overlapped without discrimination. CONCLUSION: We detected higher levels of anti-retina antibodies in uveitis patients and in a small fraction of asymptomatic patients with chronic toxoplasmosis. The presence of anti-retina antibodies in sera might be a marker of eye disease in asymptomatic patients, especially when whole human retina extract is used in a solid-phase ELISA.

Evidências sorológicas e experimentais da resposta autoimune humoral contra a retina em uveites causada por Toxoplasma gondii / Experimental and serological evidence of humoral autoimmune response against retina in Toxoplasma gondii uveitis

A toxoplasmose ocular é atribuída ao parasita, mas a auto-imunidade pode participar do processo. Soros humanos com IgG positiva para T. gondii mostraram níveis altos de IgG anti-retina para diferentes antígenos, se comparados com soros negativos para T. gondii, uveítes de outras origens também tiveram títulos elevados. Hamsters imunizados e/ou infectados não mostraram estes anticorpos sem mimetismo antigênico. A retinocoroidite por Toxoplasma induz resposta humoral auto-imune contra antígenos da retina, provavelmente piorando o efeito direto do agente. Estes anticorpos podem ser usados como marcadores de doença ocular em pacientes soropositivos para toxoplasmose pela triagem de lesão ocular.

Ocular toxoplasmosis is attributed to the parasite, but autoimmunity could have a role in this process. Human sera, positive of anti-T. gondii IgG, show high levels of anti-retina IgG, measured by several antigens, as compared to T. gondii seronegative samples. Sera from patients with uveitis from other origins also had higher anti-retina abs levels. Challenged and/or immunized hamsters showed low anti-retina abs levels, without antigen mimicry. Toxoplasmic retinochoroiditis presents a humoral anti-retina abs, probably worsening the parasite direct effect. Those antibodies could be used as markers of eye involvement in toxoplasmosis seropositive patients, as a screening for eye examination.

AgS e uveítes endógenas humanas; um assunto polêmico / The endogenous uveitis and S-antigen; a controversal subject

Os mecanismos imunopatogênicos possivelmente envolvidos nas uveítes endógenas humanas sempre exerceram enorme fascínio sobre os oftalmologistas. Neste trabalho procurou-se sintetizá-los, com ênfase na participaçäo da auto-imunidade retiniana, particularmente a do antígeno S que representa a sua expressäo máxima. A literatura foi revista e discutida

ERG e AgS em filhos de pacientes com retinose pigmentar / ERG and AgS in children of patients with pigmentary retinosis

Realizamos a presente monografia com o objetivo básico de tentar diagnosticar precocemente a Retinose pigmentar em filhos de portadores dessa doença. Submetemos 40 pacientes a exame oftalmológico completo, eletrorretinograma e pesquisa de sensibilidade ao antígeno retiniano solúvel: teste cutâneo, pesquisa de anticorpos por hemaglutinaçäo (anti-úvea e anti-retina) e teste de inibiçäo de aderência dos leucócitos (LAI-S), sendo 20 pacientes näo descendentes de portadores de Retinose pigmentar (grupo controle) e 20 filhos de portadores de Retinose pigmentar. A comparaçäo entre os dois grupos é mostrada nas tabelas I e II. Verificamos que alguns pacientes apresentaram somente alteraçöes eletrorretinográficas ou nos testes de pesquisa do AgS, enquanto outros mostraram tanto um ERG alterado como títulos positivos ao AgS nos testes imunológicos. O ERG foi normal no grupo controle; nos filhos de portadores de Retinose pigmentar, houve 2 casos extintos e vários subvoltados. Um dos casos extintos também mostrou nítida positividade aos testes imunológicos. O ERG extinto em filhos de portadores de Retinose pigmentar deve ser considerado um valioso dado de alerta