Influence of Trimethoprim-Sulfamethoxazole for the Recurrence of Ocular Toxoplasmosis

The investigators study aims to determine the effect of prophylactic therapy with Trimethoprim-sulfamethoxazole on the recurrences of toxoplasma retinochoroiditis gondii. This is a randomized, double-masked, in patients with eye condition of acute Toxoplasma gondii retinochoroiditis. Volunteers will be recruited with a previous diagnosis of chorioretinitis presumed Toxoplasma gondii, which show active lesions compatible with recurrence. After the acute phase of treatment of all patients \[1 tablet Trimethoprim-sulfamethoxazole (800/160mg) 12/12h during 45 days\], the same Stratified by gender) will be randomized in a 1:1 ratio between the group 1 - TMP-SMZ (prophylactic treatment with trimethoprim-sulfamethoxazole 1 tablet every other day for 311 days) or group 2 - placebo (consisting of a placebo pill containing no active ingredient of similar appearance to trimethoprim-sulfamethoxazole, 1 tablet every other day for 311 days). The primary outcomes are incidence of episodes of recurrent chorioretinitis by toxoplasmosis in the follow up of 12, 36, 48, 60, 72, 84, 96, 108, and 120 months. Patients will be followed during the ten years in uveitis clinic at intervals defined as follows: return weekly for 4 weeks, then monthly for 2 months, then each 3 months for 9 months, and finally annually for 10 years.