Outer retinal toxoplasmosis.

Toxoplasma gondii is a neurotrophic organism that affects the neurosensory retina in humans. Typical ocular toxoplasmosis involves the inner retina and is associated with marked vitreous reaction. A subset of this clinical spectrum is characterized by gray-white macular lesions at the level of the outer retina. This outer retinal lesion is associated with little or no vitreous reaction. The authors report five additional cases of outer retinal toxoplasmosis. Recognition of this variation is important; prompt treatment, before serologic confirmation, resulted in marked visual improvement in all cases.