Differential diagnosis of retinitis and choroiditis in patients with acquired immunodeficiency syndrome.

Patients with acquired immunodeficiency syndrome (AIDS) are at high risk for developing retinitis. The most common forms of retinitis in such patients are those caused by cytomegalovirus (CMV) and Toxoplasma; however, retinitis or choroiditis can also be caused by other viral, protozoal, bacterial, and fungal agents. Differential diagnosis of these infections is based on a number of factors, including ophthalmoscopic appearance, underlying disease, clinical history, and severity of underlying immunosuppression. Rapid and accurate diagnosis is essential in preserving functional vision, as some forms of retinitis are rapidly progressive and since appropriate treatment varies by diagnosis.