Mariza Toledo de Abreu

A follow-up study of Toxoplasma gondii infection in southern Brazil ☆

PURPOSE To understand better the natural history of ocular toxoplasmosis by reexamining a well-characterized population in Southern Brazil. METHODS Ophthalmological examination and serologic tests for Toxoplasma gondii infection were performed in 1997 on 383 individuals who had undergone the same evaluation in 1990. RESULTS Of 109 seronegative subjects in 1990, 21 (19.3%) became seropositive by 1997, and 2 (1.5% of previously seronegative patients; 9.5% of those known to have seroconverted) developed ocular toxoplasmosis. Seroconversion occurred more frequently in individuals under 17 years of age (16 of 46 patients, 34.8%) than in those greater than 17 years of age (5 of 63 patients, 7.9%; p = 0.002). Of 131 seropositive individuals who did not have ocular lesions in 1990, 11 (8.3%) had typical toxoplasmic lesions in 1997. Of the 13 individuals with non-specific hyperpigmented small retinal lesions in 1990, 3 (23%) presented with typical lesions in 1997. CONCLUSIONS Acquired T. gondii infection can result in late development of ocular lesions. Small, non-specific hyperpigmented retinal lesions may represent sites of T. gondii infection in seropositive individuals.

Ultrasonic fragmentation of cataract in uveitis.

Thirty-nine eyes with uveitis from various causes, and complicated by cataract and vitreous opacification, underwent pars plana lensectomy and vitrectomy by ultrasonic fragmentation. Anatomical results were excellent, with clearing of all lens and vitreous opacities in all eyes. Visual results showed that there was no exacerbation and no recurrence of the uveitis. Visual results depended mainly on the presence of previous damage of the uveitis to the retina and optic nerve. Visual results did not depend on the presence of uveitis activity at the time of the surgery. Complications that occurred were cystoid macular edema, which was present in 17.94% of the eyes and diagnosed in some eyes at the surgery, retinal detachment in one eye (2.56%), sterile hypopyon in one eye (2.56%), and ultrasonic lesion of the retina in one eye (2.56%). Visions of 20/20 to 20/40 were obtained in 23% of the eyes, 20.5% had vision between 20/50 and 20/80, and 56.4% had vision of 20/100 or less. The good results justify the surgical intervention in cases of cataracts associated with uveitis. Pars plana lensectomy and vitrectomy appears to be the procedure of choice in removal of cataracts secondary to uveitis.

Arachidonic acid cascade and platelet-activating factor in the network of eye inflammatory mediators: therapeutic implications in uveitis

The cellular and biochemical events triggered by uveitis involve a complex array of cells and a heterogeneous network of mediators of intraocular inflammation. Resident cells are activated and inflammatory cells are recruited. Chemical mediators from the arachidonic acid cascade, prostaglandins, hydroxyeicosatetraenoic acids, and leukotrienes, are formed. Several of these metabolites are modulators of cellular functions, but when generated in sustained, excessive amounts, they contribute to enhanced vascular permeability and to the onset of pathophysiological responses. Another very active membrane-derived mediator is plateletactivating factor. This important mediator of immune and inflammatory responses may play a central role in uveitis due to cell priming, since interleukin-1, tumor necrosis factor, and other as yet unidentified mediators are also being generated. The concomitant accumulation of these networks of mediators in various parts of the uveal tract leads to spreading of the intraocular inflammatory response and cellular damage. At both early and late stages of uveitis, the generation of free radicals is also a major contributor to the impairment of function. Free radicals are generated in two distinct sites: in the oxidative burst of recruited white cells and in free radical formation and lipid peroxidation in resident cells. The identification of the cellular events that lead to the accumulation of networks of mediators of inflammation and their effects has important therapeutic implications in uveitis.

T-Lymphocyte Subsets in the Aqueous Humor and Peripheral Blood of Patients with Acute Untreated Uveitis

We evaluated T-lymphocyte subsets in 18 patients with active untreated uveitis and in 20 controls by monoclonal OKT (Ortho-Kung-T cell) antibodies. Both OKT4- and OKT8-positive cells were detected in the aqueous humor of patients with uveitis. The percentage of OKT4-positive cells (21.1 +/- 7.4) was larger than that of OKT8-positive cells (15.2 +/- 5.3) and the OKT4-OKT8 ratio was 1.40 +/- 0.3. A comparison of aqueous humor and peripheral blood cells from patients with uveitis showed diminished frequencies of OKT4- and OKT8-positive cells. The OKT4-OKT8 ratios were not significantly different. A comparison of peripheral blood cells from patients with uveitis and from controls showed that patients with uveitis had lower OKT4-OKT8 ratios. Lower percentages of OKT4-positive cells were also observed in the peripheral blood cells of patients with uveitis.

Ocular histoplasmosis-like syndrome: a report from a nonendemic area

PURPOSE To report some cases of ocular histoplasmosis-like syndrome from a nonendemic area. DESIGN Observational case series. METHODS This is a prospective study of 16 eyes from 8 immunocompetent patients evaluated between January 2001 to September 2005. Six patients were female and 2 male aged between 20 to 44 years, average 28 years. All patients presented clinical features that resembled ocular histoplasmosis. All patients had a negative antibody test for histoplasmosis and negative medical and laboratory evaluation of toxoplasmosis, syphilis, and tuberculosis. All patients were submitted to a complete ocular examination including fluorescein angiography. One patient was submitted to indocyanine green angiography. RESULTS Five patients presented the classical triad of clinical features that include peripapillary scarring, histo spots, choroidal neovascularization, one patient presented enlargement of atrophic chorioretina scar, one patient presented multiple retinal pigment epithelial detachment, one, neovascularized retinal pigment epithelial detachment. Another patient presented only histo spots. CONCLUSION These findings of ocular histoplasmosis-like syndrome in patients with negative antibody serum test from a nonendemic area suggest that other agents could cause these similar fundus findings of ocular histoplasmosis.

Direct fluorescent antibody assay and polymerase chain reaction for the detection of Chlamydia trachomatis in patients with vernal keratoconjunctivitis

OBJECTIVES: To identify Chlamydia trachomatis via polymerase chain reaction and a direct fluorescent antibody assay in patients with vernal keratoconjunctivitis while comparing the efficacies of both tests for detecting Chlamydia trachomatis in these conditions. METHODS: Conjunctival scraping samples were obtained from 177 patients who were divided into two groups: a vernal keratoconjunctivitis group (group A) and a control group (group B). The polymerase chain reaction and a direct fluorescent antibody assay were performed. Sensitivity, specificity, receiver operating characteristic curves, and areas under the curve were calculated for both tests in groups A and B. Receiver operating characteristic curves were plotted using a categorical variable with only two possible outcomes (positive and negative). RESULTS: Statistical analysis revealed a significant association between vernal keratoconjunctivitis and Chlamydia trachomatis infection detected by a direct fluorescent antibody assay with high sensitivity and specificity. All patients in group A with positive polymerase chain reactions also presented with positive direct fluorescent antibody assays. CONCLUSION: The association between vernal keratoconjunctivitis and Chlamydia trachomatis infection was confirmed by positive direct fluorescent antibody assays in 49.4% of vernal keratoconjunctivitis patients and by positive polymerase chain reactions in 20% of these patients. The direct fluorescent antibody assay detected Chlamydia trachomatis in a higher number of patients than did the polymerase chain reaction. Although the diagnosis of trachoma is essentially clinical, the disease may not be detected in vernal keratoconjunctivitis patients. Due to the high frequency of chlamydial infection detected in patients with vernal keratoconjunctivitis, we suggest considering routine laboratory tests to detect Chlamydia trachomatis in patients with severe and refractory allergic disease.

Validade da topografia de córnea na cirurgia refrativa com excimer laser

PURPOSE: To evaluate the refractive results and safety of PRK (photorefractive keratectomy) based on the preoperative corneal topography. METHODS: 44 operated eyes, using the photorefractive keratectomy process, and which presented preoperative topographical abnormalities. The control group consisted of 44 eyes with preoperative normal corneal topography. Eighty-eight eyes were submitted to the photorefractive keratectomy process using the Summit Apex plus Excimer Laser. Corneal topographies were accessed by the EyeSys Analysis system; the topographic abnormalities which were considered are the following: apex displacement above 1.5D (AD), asphericity above 0.25D/mm (AS), obliquity above 15 degrees (OB), inferior-superior asymmetry equal to or more than 1.5D (IS), curvature above 47D (CU) and two combined features (CB). Main measured outcome: loss of one or more lines were safety defined for the prognosis. RESULTS: All patients were followed up during 6 months. A significant loss of BCVA occurred in PRK-AD (p<0.001) and PRK-CO (p<0.05). CONCLUSION: These data suggest that patients, who wish to be submitted to the refractive surgery must undergo preoperative corneal topography analysis and if any topographic abnormality is found in these patients, this can indicate the loss of lines of corrected vision after surgery.

Remote hypofluorescent dots in recurrent ocular toxoplasmosis on indocyanine green angiography

PURPOSE To report the findings of indocyanine green angiography performed in patients with recurrent ocular toxoplasmosis. METHODS Institutional prospective analysis of 23 eyes from 23 immunocompetent patients with recurrent ocular toxoplasmosis aged between 17 and 41 years. These patients underwent a complete ocular examination including indocyanine green angiography. RESULTS Multiple hypofluorescent spots distant from the recurrent active lesion of retinochoroidal toxoplasmosis were found in 26.08% of the patients. We also found multiple hypofluorescent satellite dots in 69.56% of the patients. CONCLUSION These remote dots seen suggest either a more widespread choroidal involvement in this disease and this can represent simply remote collections of inflammatory cells or subclinical infection.

Ocular masquerade syndrome due to intraocular lymphoma - two forms of retinal pigment epithelium involvement: case reports

Ocular masquerade syndrome was diagnosted in two patients with chronic uveitis. The patients presented non-Hodgkins lymphoma as the final diagnosis two forms of intraocular retinal pigment epithelium involvement was seen. One case was flecks of the retinal pigment epithelium and another case was a solid retinal pigment epithelium detachment. These unusual presentations of non-Hodgkins lymphoma is an alert to all involved in lymphoma care.

Características psicológicas e força de ego dos pacientes com uveíte de Behçet comparados a outras uveítes

Este estudo duplo-cego comparou dois grupos de pacientes: 9 com Sindrome de Behcet e 21 do grupo-controle com as seguintes uveites: toxoplasmose, tuberculose, sarcoidose, Vogt-Koyanagi-Harada e uveite anterior. O estudo incluiu duas entrevistas e o Teste Desiderativo. As caracteriticas psicologicas e a forca do ego foram similares, contrariando outras publicacoes de estudos nao controlados. Os pacientes com Sindrome de Behcet nao apresentaram personalidade diferente dos pacientes com outras uveites. Os resultados mostraram egos fracos, dificuldades pessoais e familiares, tendencia a repressao de afetos e emocoes, ansiedade e imaturidade emocional em todos os pacientes com uveites