Antibiotics for toxoplasmic retinochoroiditis: an evidence-based systematic review

Abstract

Purpose: To determine the effectiveness of systemic antibiotic treatment for toxoplasmic retinochoroiditis.

Clinical relevance: Toxoplasma retinochoroiditis is a significant cause of visual morbidity. Multiple different antibiotic regimens are used, but controversy about treatment effectiveness remains.

Literature reviewed: Searches were conducted of Cochrane Controlled Trials Register, Medline (1966 onward), Embase (1980 onward), Dissertation Abstracts (1861 onward), Lilacs (1982 onward), and Pascal (1984 onward). Pharmaceutical companies were contacted for unpublished data. Any randomized controlled trials that compared antibiotics versus placebo in immunocompetent patients with toxoplasmic retinochoroiditis were retrieved. Primary outcome measures were long-term visual acuity and risk of recurrent retinochoroiditis. Secondary outcomes included duration and severity of acute symptoms, size of the lesion at end of follow-up, and adverse effects of treatment.

Results: Only 3 studies (total of 173 participants) were randomized controlled trials and hence met the inclusion criteria (level II). All 3 were methodologically poor, and 2 were carried out more than 35 years ago. None reported the effect on long-term visual outcome. We found no evidence for a beneficial effect on the duration and severity of signs of acute toxoplasmic retinochoroiditis (A,II). There was weak evidence for an effect of long-term treatment for chronic recurrent toxoplasmic retinochoroiditis on lesion recurrence. Treatment was associated with adverse effects.

Conclusions: There is a lack of evidence to support routine antibiotic treatment for acute toxoplasmic retinochoroiditis. Placebo-controlled randomized trials of antibiotic treatment in patients presenting with acute or chronic toxoplasmic retinochoroiditis arising in any part of the retina are required.