Trimethoprim-sulfamethoxazole can be used both acutely and prophylactically in patients with Toxoplasma gondii retinochoroiditis.
Reviewed by João Paulo Fernandes Felix, MD
São Paul-The use of trimethoprim-sulfamethoxazole for 2 years in patients with Toxoplasma gondii retinochoroiditis may prevent recurrences, said João Paulo Fernandes Felix, MD, Universidade Estadual de Campinas, São Paulo.
Dr. Felix has been part of a single-center, prospective, double-masked clinical trial to compare the effects of both 1 year and 2-year treatment with trimethroprim-sulfamethoxazole to reduce the recurrence of toxoplasmosis.
This area of research is important because ocular toxomoplasis is the main cause of infectious uveitis in the world, Dr. Felix said.
“It’s associated with recurrent episodes of active retinal disease,” he said.
Investigators in the study conducted their 2-year follow-up with 121 patients. For inclusion in the study, patients had to have recurrent Toxoplasma gondii retinochoroiditis and a preexisting retinochoroidal scar.
Exclusion criteria included an age under 18, those who were immunocompromised or on immunosuppressive treatments, and concomitant retinochoroiditis from other causes.
Patients received the medication twice a day for 45 days and were compared against a placebo group.
The recurrence rate in the group receiving trimethoprim-sulfamethoxazole was 0 at both 1 year and 2 years. In the placebo group, recurrence occurred in 3 patients at 1 year and 11 patients at 2 years, leading to a recurrence rate of 19.6% in the placebo group, compared with 0% in the medication group. No adverse events occurred.
“This 2-year follow-up suggests a long-term benefit. Prophylactic treatment may reduce the recurrences of toxoplasmic retinochoroiditis in the long-term period,” Dr. Felix said.
When the acute treatment ended and the eye was quiet, Dr. Felix and fellow investigators used trimethoprim-sulfamethoxazole as prophylactic treatment for up to a year after acute treatment.
João Paulo Fernandes Felix, MD
This article was adapted from Dr. Felix’s presentation at the 2015 meeting of the American Academy of Ophthalmology. Dr. Felix did not indicate any proprietary interest in the subject matter.