AIDS-Related Retinal Disorders
Retinal disorders in AIDS involve either AIDS-associated microangiopathy or infection.
Up to 80% of all AIDS patients have retinal disorders as aresult of the disease. Other ocular involvement is rare.
The pathogenesis of microangiopathy is still unclear. Oppor-tunistic infections are frequently caused by viruses.
Microangiopathy is usually asymptomatic. Patients with infec-tious retinal disorders report loss of visual acuity and visual field defects.
Ophthalmoscopic findings inAIDS-associatedmicroangiopathy include hemorrhages, microaneurysms, telangiectasia,and cotton-wool spots. Direct involvement of vascular endothelial cells in HIV infection or immune-complex-mediated damage to endothelial cells and vascular structures is thought to play a role.
Cytomegalovirus retinitis occurs in 20 â€“ 40% of older patients. Peripheralretinal necrosis and intraretinal bleeding (Fig. 12.35) are frequently observed. Vascular occlusion is rare. Secondary rhegmatogenous retinal detachment may develop. These lesions heal to produce fine granular pigment epithelial scars.
Less frequently, AIDS may involve retinal infection caused by herpes sim-plex and varicella-zoster viruses, Toxoplasma gondii, or Pneumocystis carinii. The diagnosis of a viral retinal infection in AIDS is confirmed byattempting to obtain positive serum cultures and by resistance testing.
Inflammatory retinal changes due to other causesshould be excluded by serologic studies.
Microangiopathy does not require treatment. Viral retinitis istreated with ganciclovir or foscarnet. Herpes simplex and varicella-zoster viruses are treated with acyclovir.
Ophthalmologic screening examinations are indicated in thepresence of known viral infection.
The prognosis for microangiopathy is verygood. Infectious retinitis will lead to blindness if left untreated. Visual acuity can often be preserved if a prompt diagnosis is made.