Ocular toxoplasmosis after the fifth decade

Abstract

PURPOSE: To describe the clinical features in patients presenting with ocular toxoplasmosis after the fifth decade and to analyze laboratory findings in comparison to uveitis history and clinical data. DESIGN: Prospective consecutive observational case series. METHODS: A prospective clinical analysis of 27 consecutive patients older than 50 years of age with primary or recurrent ocular toxoplasmosis was performed during a period of 8 years. These cases account for 12% of all ocular toxoplasmosis cases irrespective of age indexed in our institution during the same period. Paired serum and aqueous humor samples were tested for anti- Toxoplasma gondii IgG, IgM, and IgA antibodies. The presence of T. gondii DNA in aqueous humor was determined by polymerase chain reaction followed by DNA hydridization method. RESULTS: Although similar in age, two groups were distinguished clinically: 12 patients (44%) presented with usual forms of retinochoroiditis (mean ± SD, 1.6 ± 0.5 disk areas [DA] in size); 15 patients (56%) presented with atypical lesions, greater than 3 DA in size (mean ± SD, 5.0 ± 2.0 DA). The second group showed a higher rate of complications ( P = .028) and a poorer visual outcome ( P = .015). Twenty-four patients (89%) had intraocular IgG production, 17 (63%) had intraocular IgA production, 3 (11%) had intraocular IgM production, and 12 (44%) had a positive T. gondii DNA detection. CONCLUSIONS: After the fifth decade, ocular toxoplasmosis remains an important cause of posterior uveitis. The combination of antibody detection by immunocapture tests with T. gondii DNA detection, both in aqueous humor, allowed the diagnosis of toxoplasmic infection in the atypical cases with large ocular lesions.