Potencial do teste IGRA (Interferon Gama Release Assay) para o diagnóstico de tuberculose ocular. Revisão e análise comparativa com o teste tuberculínico cutâneo (PPD) / The potential of the IGRA (Interferon Gamma Release Assay) test for the diagnosis of ocular tuberculosis. Review and comparative analysis with the tuberculosis skin test

Resumo A detecção precisa da infecção latente por tuberculose está se tornando cada vez mais importante devido ao aumento do uso de medicamentos imunossupressores e da epidemia do vírus da imunodeficiência humana, o que aumentou o risco de reativação à tuberculose ativa (TB). O Teste IGRA QuantiFERON® TB Gold apresenta vantagens frente ao teste de PPD como por exemplo, requer somente uma coleta de amostra sanguínea ; não há necessidade que o paciente retorne ao laboratório para leitura e interpretação dos resultados; Os resultados são objetivos, não requerem interpretação do leitor ou interferência de critérios subjetivos; trata-se de um teste in vitro, portanto não há "efeito booster" (potenciação da reação tuberculínica); o teste não é afetado por vacinação prévia por BCG ou infecção por outras espécies de micobactérias. Limitações são descritas, apesar de raras, como reações cruzadas deste método com infecções por algumas espécies de micobactérias não-tuberculosis (incluindo Mycobacterium kansasii, Mycobacterium szulgai e Mycobacterium marinum). Ainda há poucos dados sobre o teste IGRA em certas populações, como por exemplo, em crianças, pacientes imunocomprometidos e mulheres grávidas. Nestes grupos, a interpretação do teste pode ser difícil e mais estudos se fazem necessários.

Abstract Precise detection of latent tuberculosis infection is becoming increasingly important due to increased use of immunosuppressive drugs and the human immunodeficiency virus epidemic , which increased the risk of reactivation to active tuberculosis (TB).The QuantiFERON® TB Gold IGRA Test has advantages over the skin test for TB, otherwise known as a Mantoux tuberculin test, for example, requires only a blood sample collection; there is no need for the patient to return to the laboratory for reading and interpretation of the results; The results are objective, do not require interpretation of the reader or interference of subjective criteria; it is an in vitro test, so there is no "booster effect" (potentiation of the tuberculin reaction); the test is not affected by prior BCG vaccination or infection with other species of mycobacteria. Limitations are described, although rare, as cross-reactions of this method with infections by some species of non-tuberculosis mycobacteria (including Mycobacterium kansasii, Mycobacterium szulgai and Mycobacterium marinum). There is still little data on the IGRA test in certain populations, such as in children, immunocompromised patients and pregnant women. In these groups, the interpretation of the test can be difficult and more studies are needed.

Serum levels of neurotrophic factors in active toxoplasmic retinochoroiditis

Abstract Toxoplasmic retinochoroiditis (TR) is the most common identifiable cause of posterior uveitis in Brazil. Response to treatment and clinical presentation may vary significantly. We assessed serum levels of brain-derived neurotrophic factor (BDNF), glial cell line-derived neurotrophic factor (GDNF), nerve growth factor (NGF), neurotrophin (NT)-3, and NT-4/5 in patients with active TR, before and after TR treatment. Methods: Twenty patients with active lesion and 15 healthy controls were enrolled in the study. Serum concentration of neurotrophic factors was determined by enzyme-linked immunosorbent assay. Results: BDNF levels were significantly higher in patients before treatment when compared with controls (p = 0.0015). There was no significant difference in pro-BDNF, NGF, GDNF, NT-3, and NT-4/5 levels between TR patients and controls. Treatment did not affect the levels of these factors. Conclusion: BDNF may be released in the context of the active TR inflammatory response.

New drug delivery system for corneal administration of mitomycin-C.

PURPOSE: To develop a new corneal release system to deliver optimum amounts of mitomycin-C (MMC) during the perioperative period of photorefractive keratectomy (PRK). SETTING: Ophthalmos S/A, São Paulo, Brazil. DESIGN: Experimental study. METHODS: An in vitro experimental design was developed for studying a new MMC delivery system at a drug concentration of 0.02%. Whatman sterile filter paper disks with a diameter of 8.0 mm were impregnated with MMC solution. After drying, the disks were placed on agar plates seeded with Staphylococcus epidermidis; this was followed by instillation of a drop of sterile water. After 1 minute, the disks were removed and the plates were incubated for 48 hours at 35°C. The mean volume of the drops delivered from regular eyedrop bottles was determined, and the inhibition zone (in millimeters) was correlated with the amount of MMC loaded onto the disks. RESULTS: Analysis of the inhibition zones produced by MMC indicated that 16 µg was the optimum dose to be incorporated in the disks. The mean volume of a drop delivered from eyedrop bottles was 37.7 µL. One minute after the application of a single drop of a balanced salt solution, the system released an adequate concentration of MMC for PRK. CONCLUSION: A new delivery system for MMC was successfully developed for application during photorefractive keratectomy. FINANCIAL DISCLOSURE: Dr. de Souza Lima Filho is the managing director of Ophtalmos S/A. Drs. de Souza Lima Filho, Irochima Pinheiro, and Oréfice have exclusive rights to intellectual property of this invention secured by a patent application filed with the Instituto Nacional da Propriedade Industrial.

Multimodal Imaging Assisting the Early Diagnosis of Cat-Scratch Neuroretinitis.

To describe how a multifocal fundus imaging system assisted the early diagnosis of cat scratch neuroretinitis in a case of a 27-year-old male with unilateral visual loss, neuroretinitis, and a peripapillary angiomatous lesion. Multimodal fundus imaging analysis was an essential contributor to the clinical diagnosis of cat scratch neuroretinitis during the early stage of the disease.

Risk of reactivation of toxoplasmic retinitis following intraocular procedures without the use of prophylactic therapy.

BACKGROUND/AIMS: Toxoplasmic retinochoroiditis is the commonest known cause of posterior uveitis worldwide and reactivation is unpredictable. Based on results from one study, the authors proposed that antitoxoplasmic therapy should be initiated as prophylaxis for intraocular surgery in patients with toxoplasmic scars. The aim of this study is to analyse the risk of toxoplasmic retinochoroiditis reactivation following intraocular procedures. METHODS: Retrospective analysis of the medical records of a total of 69 patients who underwent intraocular surgery and presented with toxoplasmic retinochoroiditis scars. RESULTS: No patient received prophylactic antitoxoplasmic therapy. Reactivation following the surgical procedure occurred in four cases, with one at 3 months and the others respectively at 13, 14 and 17 months. CONCLUSIONS: Our study shows that intraocular surgery did not result in a significant reactivation rate of toxoplasmic retinochoroiditis in the absence of preoperative prophylactic antitoxoplasmic therapy.

Morphometric changes in C57BL/6 mice retina infected by Toxoplasma gondii ME 49 strain.

This study evaluated the morphometric implications in C57BL/6 mouse retina infected by Toxoplasma gondii, ME 49 strain. Twenty C57BL/6 female mice were divided into group 1 (n=8, intraperitoneally infected with 30 cysts of T. gondii ME 49 strain) and group 2 (n=12 non-infected controls). The eyes were enucleated on the 60th day after infection, fixed and processed for light microscopy. Changes in retinal thickness and in the perimeter/area ratio (P/A) of the retinal layers were analyzed by digital morphometry. We considered that P/A was the measurement of retinal architecture distortion induced by toxoplasmosis. This study considered the ganglion cells and nerve fiber layers as a monolayer, thus six layers of retina were evaluated: photoreceptors (PRL), outer nuclear (ONL), outer plexiform (OPL), inner nuclear (INL), inner plexiform (IPL) and ganglion cells/nerve fiber monolayer (GNL). Histological analysis of infected mouse retina showed inflammatory infiltrate, necrosis, glial reaction and distortion of the retina architecture. It also presented increased thickness (167.8±24.9µm versus 121.1±15.4µm, in controls) and increased retinal thickness within the retinitis foci (187.7±16.6µm versus 147.9±12.2µm out of the retinitis foci). A statistically significant difference in P/A was observed between infected and uninfected mouse retinas. The same was observed in PRL, OPL, INL and GNL. Retinal morphometry may be used to demonstrate differences between infected and uninfected mouse retinas.

Interleukin-6 gene polymorphism (-174 G/C) is associated with toxoplasmic retinochoroiditis.

PURPOSE: Experimental data have demonstrated a relevant role for IL-6 in the modulation of acute ocular toxoplasmosis. Therefore, we aim to investigate the possible association between the IL-6 gene polymorphism at position -174 and toxoplasmic retinochoroiditis (TR) in humans. METHODS: Ninety-seven patients with diagnosed TR were recruited from the Uveitis Section, Federal University of Minas Gerais. For comparison, 83 healthy blood donors with positive serology for toxoplasmosis and without retinal signs of previous TR were included in the study. Genomic DNA was obtained from oral swabs of individuals and amplified using polymerase chain reaction (PCR) with specific primers flanking the locus -174 of IL-6 (-174G/C). PCR products were submitted to restriction endonuclease digestion and analysed by polyacrylamide gel electrophoresis to distinguish allele G and C of the IL-6 gene, allowing the detection of the polymorphism and determination of genotypes. RESULTS: There was a significant difference in the genotype (χ(2) = 12.9, p = 0.001) and allele (χ(2) = 6.62, p = 0.01) distribution between TR patients and control subjects. In a subgroup analysis, there was no significant difference in genotypes and allele frequencies regarding TR recurrence. CONCLUSIONS: This study suggests that the genotypes related with a lower production of IL-6 may be associated with the occurrence of TR.

Increased serum levels of soluble tumor necrosis factor receptor-2 (sTNFR2) in patients with active toxoplasmic retinochoroiditis

This study aimed to investigate the serum levels of the cytokine TNF-α and its soluble receptors (sTNFR1 and sTNFR2) in patients with toxoplasmosis retinochoroidits (TR) and controls. 37 patients with TR and 30 subjects with positive serology for toxoplasmosis but without history and signs of uveitis were included in this study. Serum concentrations of TNF-α, sTNFR1, and sTNFR2 were determined by ELISA. Serum concentrations of TNF-α and sTNFR1 were similar in controls (mean ± SD median values; 56.57 ± 141.96 and 504.37 ± 163.87, respectively) and TR patients (mean ± SD values, 121.62 ± 217.56 and 511.15 ± 189.30, respectively). Serum concentrations of sTNFR2 were higher in the uveitis group when compared to the control group (respectively, mean ± SD values, 1734.84 ± 379.32 and 1442.75 ± 309.47; p=0.002). There was no association between the serum levels of the molecules and the time of first symptoms, severity of vitreous haze, size or localization of active lesions, levels of visual acuity, and presence of vasculitis. These results suggest that TR is associated with changes in the circulating levels of inflammatory biomarkers, but they are not correlated with local/ocular signs.

Increased serum levels of soluble tumor necrosis factor receptor-2 (sTNFR2) in patients with active toxoplasmic retinochoroiditis.

This study aimed to investigate the serum levels of the cytokine TNF-α and its soluble receptors (sTNFR1 and sTNFR2) in patients with toxoplasmosis retinochoroiditis (TR) and controls. 37 patients with TR and 30 subjects with positive serology for toxoplasmosis but without history and signs of uveitis were included in this study. Serum concentrations of TNF-α, sTNFR1, and sTNFR2 were determined by ELISA. Serum concentrations of TNF-α and sTNFR1 were similar in controls (mean ± SD median values; 56.57±141.96 and 504.37±163.87, respectively) and TR patients (mean ± SD values, 121.62±217.56 and 511.15±189.30, respectively). Serum concentrations of sTNFR2 were higher in the uveitis group when compared to the control group (respectively, mean ± SD values, 1734.84±379.32 and 1442.75±309.47; p=0.002). There was no association between the serum levels of the molecules and the time of first symptoms, severity of vitreous haze, size or localization of active lesions, levels of visual acuity, and presence of vasculitis. These results suggest that TR is associated with changes in the circulating levels of inflammatory biomarkers, but they are not correlated with local/ocular signs.

Review for disease of the year: differential diagnosis of ocular toxoplasmosis.

The diagnosis of ocular toxoplasmosis is mainly clinical, based in the presence of focal necrotizing retinochoroiditis often associated with a preexistent chorioretinal scar, and variable involvement of the vitreous, retinal blood vessels, optic nerve, and anterior segment of the eye. Recognition of this clinical spectrum of toxoplasmic retinochoroiditis is crucial, but other infectious, noninfectious, and neoplastic entities should also be considered in the differential diagnosis. Investigations such as serological tests, polymerase chain reaction of ocular fluids, and assessment of intraocular antibody synthesis are helpful in uncertain cases. This article provides an overview of the differential diagnosis of ocular toxoplasmosis, focusing on the most important entities to be considered and emphasizing distinctive features of each one of them in the clinical setting. Ocular toxoplasmosis has multiple clinical manifestations, which partially overlap with those of other entities and these should be carefully considered when making the differential diagnosis, particularly in less typical cases.

Imunologia da retinocoroidite toxoplásmica / Immunology of the toxoplasmic retinochoroiditis

A infecção pelo Toxoplasma gondii é uma importante causa de doença ocular, tanto em indivíduos imunocomprometidos como em imunocompetentes. A patogênese da destruição retinocoroidiana associada a essa infecção ainda não está totalmente esclarecida. Nesta revisão, discute-se o papel do sistema imune no controle da infecção pelo Toxoplasma, especialmente, no olho.

Toxoplasma gondii infection is an important cause of ocular disease in both immunocompromised and immunocompetent subjects. The pathogenesis of retinochoroidal lesion associated with this infection is not fully understood. In this review, the role of the immune system in the control of Toxoplasma infection, especially in the eye, is discussed.

Cat-scratch disease: ocular manifestations and visual outcome.

To describe the intra-ocular manifestations of cat-scratch disease (CSD) found at two uveitis reference centers in Brazil. Retrospective case series study. Review of clinical records of patients diagnosed with CSD in the Uveitis Department of São Geraldo Hospital and the Ophthalmology Department of the Instituto de Pesquisa Clínica Evandro Chagas-FIOCRUZ, from 2001 to 2008. In the 8-year period, 24 patients with the diagnosis of CSD were identified. Twelve patients were male and 12 female. The mean age was 27.04 years (range 7-56). Sixteen patients (66.6%) presented with a history of a cat scratch and all patients reported cat exposure. Visual acuity ranged from counting fingers to 1.0 in the affected eye. Thirteen patients presented with bilateral disease. Sixteen (66.6%) patients complained of systemic symptoms, including fever, lymphadenopathy, liver and spleen enlargement and rash. All patients presented with serum antibodies (IgG) to Bartonella henselae. Thirty-seven eyes were affected. The most common findings were small areas of retinal infiltrates which occurred in 11 eyes (29.7%) and angiomatous lesions which occurred in nine eyes (24.3%). Neuroretinitis occurred in only six eyes (16.2%). The most common findings of CSD in our study were retinal infiltrates and angiomatous lesions. CSD patients may present with significant visual loss. Patients may benefit from systemic treatment with antibiotics.

Anti-Toxoplasma gondii secretory IgA in tears of patients with ocular toxoplasmosis: immunodiagnostic validation by ELISA

Toxoplasma gondii causes posterior uveitis and the specific diagnosis is based on clinical criteria. The presence of anti-T. gondii secretory IgA (sIgA) antibodies in patients' tears has been reported and an association was found between ocular toxoplasmosis and the anti-T. gondii sIgA isotype in Brazilian patients. The purpose of this study was to provide an objective validation of the published ELISA test for determining the presence of anti-T. gondii sIgA in the tears of individuals with ocular toxoplasmosis. Tears from 156 patients with active posterior uveitis were analysed; 82 of them presented characteristics of ocular toxoplasmosis (standard lesion) and 74 patients presented uveitis due to other aetiologies. Cases of active posterior uveitis were considered standard when a new inflammatory focus satellite to old retinochoroidal scars was observed. The determination of anti-T. gondii sIgA was made using an ELISA test with crude tachyzoite antigenic extracts. Tears were collected without previous stimulation. Detection of sIgA showed 65.9 percent sensitivity (95 percent CI = 54.5-74.4), 71.6 percent specificity (95 percent CI = 59.8-81.2), a positive predictive value of 72 percent (95 percent CI = 60.3-81.5) and a negative predictive value of 65.4 percent (95 percent CI = 54.0-75.4). sIgA reactivity was higher in the tears of patients with active posterior uveitis due to T. gondii (p < 0.05). The test is useful for differentiating active posterior uveitis due to toxoplasmosis from uveitis caused by other diseases.

Esclerite posterior: características clínicas, associação sistêmica, tratamento e evolução de 23 pacientes / Posterior scleritis: clinical features, systemic association, treatment and evolution of 23 patients

OBJETIVOS: Documentar características clínicas, associações sistêmicas, tratamento e evolução de 23 pacientes com esclerite posterior, examinados no serviço de uveítes da Universidade Federal de Minas Gerais. MÉTODOS: Revisão de todos os pacientes com esclerite atendidos neste serviço, de 1999 até 2006, para identificar aqueles com esclerite posterior. Identificados 23 pacientes, registrados e analisados os dados com relação aos sinais e sintomas oculares, visão, alterações na ecografia, manifestações sistêmicas, tratamento e evolução. RESULTADOS: Dezesseis pacientes do sexo feminino e 7 do sexo masculino com média de idade de 44,7 anos. Esclerite posterior ocorreu associada à esclerite anterior em 10 pacientes, envolvimento unilateral em 17 pacientes e, bilateral simultâneo, em 6 pacientes. Esclerite posterior associada à doença sistêmica ocorreu em 8 pacientes (síndrome de Cogan, tuberculose, granulomatose de Wegener, herpes simples e zoster, aspergilose, retocolite-ulcerativa e sarcoidose). A principal queixa foi dor ocular seguida de embaçamento visual e o sinal fundoscópico que predominou foi o descolamento seroso de retina. O achado mais comum na ecografia foi espessamento da parede escleral observado em 18 pacientes e a principal forma de tratamento, o uso de corticóide sistêmico. Somente 4 pacientes necessitaram de imunossupressor. CONCLUSÃO: Esclerite posterior é doença de difícil diagnóstico e pode ser potencialmente devastadora. Análises estatísticas são incapazes de revelar outras características específicas da esclerite posterior, características clínicas dos pacientes e evolução da doença que poderiam ajudar na identificação dos casos com maior risco de perda visual ou com maior probabilidade de doença sistêmica.

PURPOSE: To document the clinical features, systemic association, treatment and evolution of 23 patients with posterior scleritis evaluated in the Uveitis service of the Federal University of Minas Gerais. METHODS: 23 patients were identified with the diagnosis of posterior scleritis. Signals and symptoms, visual acuity, B-mode ultrasonography signals, systemic associations, treatment and evolution were described and analyzed. RESULTS: Sixteen patients were female and seven were male with mean age of 44,7 years. Posterior scleritis occurred in association with anterior scleritis in 10 patients, unilateral involvement in 17 patients and simultaneous bilateral involvement in 6 patients. Posterior scleritis in association with systemic disease occurred in 8 patients (Cogan's syndrome, TBC, Wegener, Herpes simplex and Zoster, Apergilosis, inflamatory bowel disease and Sarcoidosis). The main symptoms were ocular pain and decrease of visual acuity and the main signal was retinal serous detachment. Increase of thickness choroidal tissue was the main signal in B-mode ultrasonography in 18 patients and the principal kind of treatment was the use of systemic corticosteroids. Only 4 patients required systemic immunosuppressive drugs. CONCLUSIONS: Posterior scleritis still represents a diagnostic challenge and is often associated with life threatening systemic disease and vision threatening ocular complications. Knowledge of posterior scleritis may aid in determining timely and accurate diagnosis and treatment of both ocular and any systemic conditions associated, thus decreasing morbidity and mortality. Elevated suspicion rate is always required to detect this condition.

Esclerite: características clínicas, associação sistêmica, tratamento e evolução de 100 pacientes / Scleritis: clinical characteristics, systemic associations, treatment and outcome in 100 patients

OBJETIVOS: Documentar características clínicas, associações sistêmicas, tratamento e evolução de 100 pacientes com esclerite, examinados no serviço de uveítes da Universidade Federal de Minas Gerais. PACIENTES E MÉTODOS: Identificados 100 pacientes com esclerite, registrados e analisados dados com relação às queixas dos mesmos, sinais oculares, visão, alterações ecográficas, manifestações sistêmicas, tratamento e evolução. RESULTADOS: Sessenta e nove pacientes eram mulheres e 31 homens. Esclerite anterior difusa e nodular ocorreu em 71 pacientes, esclerite anterior necrosante em 3, esclerite posterior em 24 e escleromalácia perfurans em 2 pacientes. Envolvimento unilateral em 79 e bilateral em 21 pacientes. A principal queixa foi dor ocular e o sinal fundoscópico predominante na esclerite posterior foi o descolamento seroso de retina. Em 13 pacientes a esclerite determinou o encontro de doença sistêmica e a principal forma de tratamento foi com droga anti-inflamatória não-esteróide oral. Dezoito pacientes precisaram de tratamento imunossupressor para o controle do quadro ocular e a incidência de complicação ocular foi de 35%. DISCUSSÃO: Esclerite é doença rara, às vezes de difícil diagnóstico e potencialmente devastadora, todos os esforços devem ser necessários para um diagnóstico rápido e correto dessa doença. O conhecimento sobre a esclerite, suas formas de apresentação, associações sistêmicas, tratamento e evolução são fundamentais para que possamos fazer este diagnóstico correto e conduzir o quadro ocular da maneira mais adequada possível tendo sempre como objetivo final o controle do quadro escleral e preservação da visão do paciente.

PURPOSE: To document the clinical features, systemic association, treatment and evolution of 100 patients with scleritis evaluated at the Uveitis Service of the Federal University of Minas Gerais. PATIENTS AND METHODS: 100 patients were identified with the diagnosis of scleritis. Signals and symptoms, visual acuity, B-mode ultrasonography signals, systemic associations, treatment and evolution were described and analyzed. RESULTS: 69 patients were female and 31 were male. Diffuse and nodular anterior scleritis occurred in 71 patients, necrotizing anterior scleritis in 3, posterior scleritis in 24 and escleromalacia perforans in 2 patients. Unilateral involvement occurred in 79 patients and bilateral involvement in 21 patients. The main symptoms were ocular pain and redness and the main signal in posterior scleritis was the serous detachment of the retina. Scleritis in association with systemic disease occurred in 35 patients and the principal kind of treatment was the use of oral NSAIDs. Only 18 patients required systemic immunosuppressive drugs. Ocular complications were detected in 35 patients. CONCLUSIONS: Scleritis may represent a diagnostic challenge and is often associated with life threatening systemic disease and vision threatening ocular complications. Knowledge of scleritis may aid in determining timely and accurate diagnosis and treatment of both the ocular and any associated systemic conditions, thus decreasing morbidity and mortality.

Imunogenética das uveítes / Imunogenetics in the uveítes

Citocinas são moléculas envolvidas na comunicação intercelular nas respostas inflamatória e imune, desempenhando papel relevante nas uveítes. Polimorfismos dos genes responsáveis pela produção de determinadas citocinas têm sido relacionados com a ocorrência e a gravidade de algumas uveítes. Portanto, o presente trabalho tem como objetivo relatar essas possíveis associações, salientando o aspecto individual genético no prognóstico das uveítes.

Cytokines are molecules involved in intercellular communication in immune and inflammatory responses, playing an important role in uveitis. Genetic polymorphisms responsible for the production of certain cytokines have been associated with the occurrence and the severity of uveitis. Therefore, the present study has the purpose of describing these possible associations, pointing out the individual genetic background in the prognosis of uveitis.