Cytologic identification of Toxoplasma gondii from vitreous fluid.

A 75-year-old man presented with a diffuse necrotizing retinitis in his left eye. Although his condition was initially diagnosed as acute retinal necrosis syndrome, the serologic test results were interpreted as indicating recurrent toxoplasmosis retinitis. Cytopathologic examination of the vitreous following pars plana vitrectomy for repair of a retinal detachment revealed Toxoplasma organisms. The observation of Toxoplasma gondii in the vitreous specimen confirmed our clinical diagnosis and helped guide treatment of the patient.