Cytomegalovirus retinitis: diagnosis and status of systemic therapy

Cytomegalovirus (CMV) retinitis is a disease of advanced immunosuppression that occurs almost exclusively in patients with CD4+ counts of < or =50 cells/mm3. Therefore, this disease usually presents in patients who have already been diagnosed with acquired immunodeficiency syndrome (AIDS). The rate of progression of untreated CMV retinitis is variable. Typical initial complaints of patients with CMV retinitis may include blurred or decreased vision, loss of peripheral or central vision, and multiple "floaters." The diagnosis of CMV retinitis requires ruling out a number of other ocular disorders that may be confused with CMV retinitis. This review discusses the different appearances of CMV retinitis at presentation and the possible retinal responses to therapy for CMV retinitis. An overview of intravenous (i.v.) ganciclovir or i.v. foscarnet as systemic therapy for treatment of CMV retinitis and their use in combination is also presented. Results indicate that combination therapy with both ganciclovir and foscarnet is more effective in controlling progression of CMV retinitis in relapsed patients than is monotherapy with either drug. However, combination systemic therapy is time-consuming, and this regimen has the greatest negative impact on quality of life. Treatment should involve a cooperative effort between the patient's ophthalmologist and the primary AIDS-treating physician. Both must be aware of the location and activity of the retinitis and of other medical conditions and concomitant medications.