To the Editor. —Cytomegalovirus (CMV) retinitis is a substantial cause of morbidity in patients with acquired immunodeficiency syndrome (AIDS). Recently, a beneficial effect of treatment with ganciclovir, an acyclovir derivative with activity against CMV in vitro, has been reported.1 Zidovudine (formerly known as azidothymidine [AZT]) is a dideoxythymidine compound with antiviral activity against human immunodeficiency virus (HIV). This study documents regression of CMV retinitis in a patient with AIDS who elected to receive zidovudine therapy without ganciclovir treatment. Report of a Case. —A 26-year-old homosexual man was diagnosed as having AIDS in July 1986, when he developed Pneumocystis carinii pneumonia. In addition, CMV and Mycobacterium avium intracellulare were recovered from a bronchoalveolar lavage specimen at this time. He recovered after three weeks of trimethoprim and sulfamethoxazole therapy. On Sept 23, 1986, he was examined for a complaint of blurred vision in his left eye. Visual acuity was 20/20