Snapshot A 38-year-old man presents to the emergency department with worsening vision loss. His symptoms are accompanied by floaters and episodes of photopsia. Medical history is significant for HIV infection, which he has been nonadherent to his antiretroviral therapy. His CD4+ count is 45/mm3. Dilated fundoscopic examination demonstrates a white, granular retinal lesion. Introduction Pathogenesis CMV hematogenously spreads to the retina and infects the vascular endothelium Overview Opportunistic infection of the retina caused by cytomegalovirus (CMV) usually seen in acquired immune deficiency syndrome (AIDS) and other immunocompromised states Epidemiology Risk factors AIDS CD4 counts < 50/mm3 Presentation Symptoms may be asymptomatic decreased visual acuity floaters photopsia or scotomas in some cases Physical exam whitish, granular retinal appearance enlarged cotton wool spots Differential HIV retinopathy differentiating factors intraretinal hemorrhages cotton wool spots microaneurysms Treatment Medical intravitreal ganciclovir or foscarnet with systemic CMV therapy indication sight-threatening CMV retinitis oral valgancyclovir indication non-sight-threatening CMV retinitis Complications Rhegmatogenous retinal detachment Prognosis Improved with antiretroviral therapy