Usefulness of aqueous and vitreous humor analysis in infectious uveitis

OBJECTIVE: To evaluate the role of intraocular fluid analysis as a diagnostic aid for uveitis. METHODS: Twenty-eight samples (27 patients including 3 HIV-infected patients) with active (n=24) or non-active (n=4) uveitis were submitted to aqueous (AH; n=12) or vitreous humor (VH) analysis (n=16). All samples were analyzed by quantitative PCR for herpes simplex virus (HSV), varicella zoster virus (VZV), cytomegalovirus (CMV), Epstein-Barr virus (EBV) and Toxoplasma gondii. RESULTS: The positivity of the PCR in AH was 41.7% (5/12), with 50% (2/4) in immunocompetent and 67% (2/3) in HIV+ patients. The positivity of the PCR in VH was 31.2% (5/16), with 13% (1/8) in immunocompetent and 50% (4/8) in immunosuppressed HIV negative patients. The analysis was a determinant in the diagnostic definition in 58% of HA and 50% of VH. CONCLUSION: Even in posterior uveitis, initial AH analysis may be helpful. A careful formulation of possible clinical diagnosis seems to increase the chance of intraocular sample analysis being meaningful.

Detection of Toxoplasma gondii DNA in peripheral blood and aqueous humor of patients with Toxoplasmic active focal necrotizing retinochoroiditis using real-time PCR / Detecção de DNA do Toxoplasma gondii no sangue periférico e humor aquoso por PCR em tempo real

ABSTRACT Purpose: To evaluate the ability of real-time quantitative PCR (qPCR) for detectingToxoplasma gondii DNA in the peripheral blood and aqueous humor of patients with toxoplasmic active focal necrotizing retinochoroiditis. Methods: Fifty-five patients with infectious uveitis seen from 2009 to 2013 at the Department of Ophthalmology and Visual Sciences of the Federal University of São Paulo were enrolled in this study. Forty-three patients had toxoplasmic active focal necrotizing retinochoroiditis, and the remaining 12 had non-toxoplasmic infectious uveitis and served as controls. qPCR analysis forT. gondii DNA was performed on the patients' peripheral blood and aqueous humor samples. Results: The qPCR was positive for T. gondii DNA in 37.21% (16/43) of the aqueous humor samples and 2.33% (1/43) of the peripheral blood samples; further, 16.27% (7/43) of the patients had positive results in both their blood and aqueous humor samples. Conclusion: qPCR was able to detect T. gondii DNA in patients with toxoplasmic active focal necrotizing retinochoroiditis in the blood as well as the aqueous humor and can help with the diagnosis of the disease.

RESUMO Objetivo: Analisar o uso do PCR em tempo real (qPCR) na detecção do DNA do T. gondii no sangue periférico e no humor aquoso de pacientes com lesões de retinocoroidite focal, ativa por toxoplasmose. Métodos: Cinquenta e cinco pacientes com uveite infecciosa foram incluídos neste estudo. Os pacientes foram atendidos entre 2009 a 2013, no Departamento de Oftalmologia e Ciências Visuais da Universidade Federal de São Paulo. Quarenta e três pacientes tiveram o diagnóstico de lesões de retinocoroidite focal, ativa por toxoplasmose e, os outros 12 tiveram o diagnóstico de uveíte infecciosa não toxoplásmica e, por isso foram usados como grupo controle. A técnica de qPCR foi utilizada na detecção de DNA do T. gondii em amostras de sangue periférico e humor aquoso. Resultados: O qPCR foi positivo para o DNA do T. gondii em 37,21% (16/43) das amostras de humor aquoso, 2,33% (1/43) nas amostras de sangue periférico e, 16,27% (7/43) em ambas amostras simultaneamente. Conclusão: O qPCR foi capaz de detectar o DNA do T. gondii em pacientes com lesões de retinocoroidite focal, ativa por Toxoplasmose, no sangue bem como, no humor aquoso, podendo ajudar no diagnostico.

Compromiso ocular en la enfermedad de Chagas congénita: Cases report / Ocular involvement in congenital Chagas disease

El compromiso ocular es una forma de presentación infrecuente en los niños con la enfermedad de Chagas congénita. Se presentan tres pacientes menores de dos meses de edad con compromiso ocular, todos ellos derivados al hospital para control oftalmológico por prematuridad. El diagnóstico oftalmológico fue de vitreítis bilateral intensa (uveítis posterior) asociada a enfermedad de Chagas. Se realizó tratamiento antiparasitario, con buena respuesta en los tres casos. Debe considerarse la enfermedad de Chagas como diagnóstico diferencial de una patología ocular en los lugares donde la enfermedad es endémica y solicitar una evaluación oftalmológica en los niños con diagnóstico de la enfermedad, en especial aquellos sintomáticos y con antecedente de prematuridad.

Ophthalmic compromise is infrequent in children with congenital Chagas disease. We present 3 patients under 2 months of age, with ocular involvement, all of them referred to the hospital for ophthalmic evaluation of the premature newborn. The ophthalmic finding was bilateral severe vitreitis (posterior uveitis) related to Chagas disease. They received antiparasitic therapy with a good outcome in all cases. Chagas disease must be considered as differential diagnosis of ocular pathology in those countries where the pathology is endemic, and fundoscopic evaluation must be done in those children with the diagnosis, especially those symptomatic and prematurely born.

Achados ultrassonográficos em toxocaríase ocular / Ultrasonographic findings in ocular toxocariasis

OBJETIVO: Avaliar achados ultrassonográficos nas três principais formas de apresentação da toxocaríase ocular (granulomas de periferia e polo posterior e endoftalmite crônica), em pacientes com diagnóstico confirmado de toxocaríase ocular. MÉTODOS: Foram analisados no estudo 11 pacientes (11 olhos), de forma prospectiva, com diagnóstico de toxocaríase forma ativa, com teste ELISA positivo. Os pacientes foram submetidos ao exame de ultrassonografia ocular (transdutor 10 MHz, técnica de contato). RESULTADOS: Na série de 11 pacientes, com idade média de 7,9 anos (variando de 2 a 17 anos), 73% homens, referiram contato prévio com cães (91%), e com solo (50%), sem referência à perversão do apetite. Na avaliação dos olhos comprometidos (11 olhos), o exame oftalmológico revelou a seguinte distribuição das três formas de toxocaríase ocular: 7 (63,6%), granuloma de polo posterior; 1 (9,1%), endoftalmite crônica; 2 (18,2%), granuloma periférico; e 1 (9,1%), quadro associado de granuloma de polo posterior e endoftalmite crônica. Acuidade visual comprometida: sem percepção luminosa (3 olhos, 27,3%); visão de vultos (4 olhos, 36,4%); contar dedos a 10 cm (1 olho, 9,1%); 20/200 (1 olho, 9,1%); 20/70 (1 olho, 9,1%); indeterminado (1 olho, 9,1%). Sorologia para Toxocara canis foi positiva (teste ELISA) em 100% dos casos. Oftalmoscopia foi difícil ou impossível em 64% dos casos devido à opacidade de meios. Características ultrassonográficas observadas: membranas vítreas com retina aplicada (100%); lesões de parede (granulomas) com refletividade alta (80%) ou média (20%). CONCLUSÃO: O achado ultrassonográfico mais consistente no olho portador de toxocaríase foi a presença de massa retiniana de alta refletividade, localizada no polo posterior ou periferia, que pode ser calcificada, e que apresenta como principal característica a aderência de membranas vítreas. Em combinação com a história, exame clínico e sorologia, a ultrassonografia pode ajudar no diagnóstico da toxocaríase ocular, principalmente nos casos com opacidade de meios.

PURPOSE: To evaluate ophthalmic ultrasound findings in the three presentation forms of ocular toxocariasis (peripheral or posterior pole granulomas and chronic endophthalmitis), in patients with confirmed diagnosis of ocular toxocariasis. METHODS: 11 patients (11 eyes) with clinical and confirmed diagnosis of active ocular toxocariasis, presented positive ELISA test, were analyzed, prospectively, in the study. The patients were submitted to an ocular ultrasound examination (10-MHz transducer, contact technique). RESULTS: In the series of 11 patients, mean age was 7.9 years-old (range from 2 to 17 y), 73% male, referring previous contact with dogs (91%), and with the soil (50%), no referral of appetite perversion. In the analyses of compromised eyes (11 eyes), the ophthalmoscopic examination revealed the following distribution of the 3 forms of ocular toxocariasis: 7 cases (63.6%), posterior pole granuloma; 1 (9.1%), chronic endophthalmitis; 2 (18.2%), peripheral granuloma; and 1 (9.1%), posterior pole granuloma associated with chronic endophthalmitis. Visual acuity impairment: no light perception (3 eyes, 27.3%); hand motion (4 eyes, 36.4%); counting fingers at 10 cm (1 eye, 9.1%); 20/200 (1 eye, 9.1%); 20/70 (1 eye, 9.1%); undefined (1 eye, 9.1%). Serology was positive to Toxocara canis (ELISA test) in 100% of the cases. Ophthalmoscopy was difficult or impossible in 64% of the cases due to the media opacity. Ultrasound findings noted were vitreous membranes with retinal attachment (100%); parietal lesions (granulomas) with high (80%) or medium (20%) reflectivity. CONCLUSION: The most consistent ultrasound finding in the eye with toxocariasis was a high-reflectivity retinal mass, located in posterior pole or periphery, which may be calcified, and which has as main characteristic the adherence of vitreous membranes. In addition to clinical history, systemic evaluation and serology, the ultrasound can help in the diagnosis of ocular toxocariasis, especially in media opacities.

Detection of Ocular Toxoplasma gondii Infection in Chronic Irregular Recurrent Uveitis by PCR

Toxoplasma gondii is a zoonotic parasite resulting in human infections and one of the infectious pathogens leading to uveitis and retinochoroiditis. The present study was performed to assess T. gondii infection in 20 ocular patients with chronic irregular recurrent uveitis (20 aqueous humor and 20 peripheral blood samples) using PCR. All samples were analyzed by nested PCR targeting a specific B1 gene of T. gondii. The PCR-positive rate was 25% (5/20), including 5% (1) in blood samples, 25% (5) in aqueous humor samples, and 5% (1) in both sample types. A molecular screening test for T. gondii infection in ocular patients with common clinical findings of an unclear retinal margin and an inflammatory membrane over the retina, as seen by fundus examination, may be helpful for early diagnosis and treatment.

Acquired and congenital ocular toxoplasmosis experimentally induced in Calomys callosus (Rodentia, Cricetidae)

An experimental model for acquired and congenital ocular toxoplasmosis as well as a model to induce experimental autoimunne uveitis (EAU) was investigated in Calomys callosus. Toxoplasma gondii, ME-49 strain, was used to infect males and pregnant and not pregnant-females while S-antigen, a major glycoprotein of the retinal photoreceptor cell, was used to induce EAU. The ocular lesions elicited by T. gondii were characterized by the presence of cysts, free tachyzoites and inflammatory cells in the retina or related tissues. In the congenital form, 40 per cent of the fetus presented ocular lesions, i.e., presence of cysts in the retina, vitreous, and extra-retinal tissues. In the acquired form, 75 per cent of the females and 50 per cent of the males presented unilateral ocular cysts both at 21 and 47 days post-infection. It was also demonstrated that S-antigen was not uveitogenic in the C. callosus model. No lesion was observed in the animals exclusively immunized with this retinal component, even when jacalin was used as addicional adjuvant for polyclonal response to the retinal antigen. It can be concluded that C. callosus may constitue in a promising model for study both acquired and congenital ocular toxoplasmosis, particularly when it is important to make sure that a non autoimmune process is involved in the genesis of the ocular infection.