Treatment of toxoplasmosis retinochoroiditis with atovaquone in an immunocompetent patient

Abstract

In Central Europe ocular toxoplasmosis is the leading cause of posterior uveitis. It is a major cause of severe visual loss and blindness in young people. Drugs for treatment of active lesions (tachyzoites) have been available for decades but are seen controversial especially because of sometimes serious side effects. These drugs don't seem to shorten the active inflammation nor the recurrence rate, in particular because of the poor effect on the cystic form (bradyzoites). Atovaquone (hydroxynaphthoquinone) is well tolerated systemically and is effective against tachyzoites and bradyzoites of Toxoplasma gondii so that we hope to reduce the recurrence rate. PATIENT HISTORY AND CLINICAL FINDINGS: Two immunocompetent patients with the first and respective second symptomatic recurrence of unilateral active toxoplasmic retinochorioiditis located within the major temporal vascular arcades were treated with Atovaquone and Fluorocortolone because of an impending loss of central visual function. Under the treatment with Atovaquone (3 x 750 mg/day) for three weeks and tapering of the Fluorocortolone the active lesions healed quickly. After a few weeks, atrophic and remarkably little pigmented scars remained. No side effects were observed. After a period of 7 and respective 11 months no recurrence occurred. Atovaquone is an effective and well tolerated drug for the treatment of active ocular toxoplasmosis in immunocompetent patients. Its efficacy against tachyzoites and cysts of Toxoplasma gondii relative to other drugs remains to be determined by further clinical trials.