[Treatment of toxoplasmosis retinochoroiditis with atovaquone in an AIDS patient].

BACKGROUND

Treatment of ocular toxoplasmosis in HIV-infected patients with standard drug regimens (Pyrimethamine, Clindamycine, Sulfonamides) is very often complicated by side-effects and adverse reactions. On the other hand, maintenance therapy must be continued life long, because of the high recurrence rates. Atovaquone (Hydroxynaphthoquinon) is tolerated excellently and is very effective against tachyzoits of toxoplasma gondii and its cysts. PATIENT HISTORY AND CLINICAL FINDINGS: A 49-year-old homosexual man with AIDS developed an allergic rash after being treated with a course of Pyrimethamine and Clindamycine for unilateral, bifocal ocular toxoplasmosis for 13 days. Therapy with Atovaquone 3 x 750 mg/d was instituted and within 8 days the infiltrates healed leaving retinochorioidal scars.

THERAPY AND CLINICAL COURSE

During maintenance therapy with Atovaquone (3 x 750 mg/d) two relapses occurred, the first after 2 months and the second after 8 months. The recurrences were successfully treated by increasing the dosage of Atovaquone to 4 x 750 mg/d and the addition of Trimethoprime/Sulfamethoxazol and Clindamycine/Pyrimethamine respectively. Reexposition was tolerated without an allergic reaction. Under maintenance therapy with Pyrimethamine the patient was free of recurrences for another 4 months until he died.

CONCLUSIONS

Atovaquone is an effective and well tolerated substance for the treatment of ocular toxoplasmosis. In contrast to earlier reports, two recurrences occurred under maintenance therapy. It cannot be excluded that the patient was incomplient and did not take the tablets according to our prescription. Future clinical investigations have to control the efficacy of Atovaquone in the therapy of ocular toxoplasmosis.