Patients with AIDS-related cytomegalovirus (CMV) retinitis receiving combined antiretroviral therapy (cART), but not specific anti-CMV therapy, consistently showed active retinitis for several months. Delayed diagnosis and treatment of CMV retinitis may have severe consequences. Patients first entering care with advanced HIV infection and vulnerability to reactivation of latent CMV infection should be screened immediately for CMV retinitis by dilated indirect ophthalmoscopy and treated with specific anti-CMV therapy without delay, in addition to cART.