CMV Retinitis and AIDS

By Judith Lee, with updates by Liz Segre

Cytomegalovirus (CMV) retinitis is a sight-threatening disease associated with late-stage AIDS. In the past, about one-fourth of active AIDS (Acquired Immunodeficiency Syndrome) patients developed CMV retinitis. However, this figure appears to be dropping thanks to a potent combination of drugs that help restore the function of the immune system.

CMV Retinitis Symptoms and Signs

When CMV invades the retina, it begins to compromise the light-sensitive receptors that enable us to see. This does not cause any pain, but you may see floaters or small specks and experience decreased visual acuity (blurry vision) or decreased peripheral vision. Light flashes and sudden loss of vision can also occur. The disease usually starts in one eye but often involves both eyes.

If left untreated, CMV retinitis can cause retinal detachment and blindness within just two to six months.

AIDS patients sometimes also experience changes to the retina and optic nerve without clear signs of CMV retinitis.

What Causes CMV Retinitis?

CMV retinitis is caused by the cytomegalovirus, a very common virus: about 80 percent of adults harbor antibodies to CMV, which indicates their bodies have successfully fought it off. The difference for people who have AIDS is that their weakened or non-functioning immune system cannot stave off this virus. Other people with a weakened or suppressed immune system, such as those undergoing chemotherapy or a bone marrow transplant, are also at risk.

According to the Centers for Disease Control and Prevention, up to 1.185 million people in the United States were living with HIV/AIDS at the end of 2003, and about 40,000 Americans were becoming infected with HIV each year.

In 2004 the CDC estimated that African Americans accounted for half of the cases diagnosed, even though this group was only 12 percent of the U.S. population.

Worldwide the figures look even worse. In November 2006 the World Health Organization estimated that 39.5 million people are living with HIV, with 4.3 million new infections in 2006; 65 percent of the new infections were in sub-Saharan Africa, where access to treatment is extremely limited. Disturbingly, infection rates in Eastern Europe and Central Asia may have risen more than 50 percent since 2004, says WHO. — L.S.

CMV Retinitis Treatment

If you have active AIDS and are experiencing visual symptoms, you should see a retina specialist immediately. A person newly diagnosed with CMV retinitis can expect to visit the specialist every two to four weeks.

Once the disease is controlled, those visits may be with your regular eye doctor every three to six months, according to Robert Kalayjian, MD, an infectious disease specialist at Case Western Reserve University School of Medicine in Cleveland.

Drugs for CMV Retinitis. The anti-viral drugs commonly used to treat CMV retinitis are ganciclovir (Cytovene), foscarnet (Foscavir) and cidofovir (Vistide). They can slow down the progression of CMV, but they can't cure it.

Like many drugs, they can cause unpleasant or serious side effects. Until recently, all three of these drugs were given intravenously, and ganciclovir and foscarnet required a permanent catheter placed in the chest for daily infusions.

Now, ganciclovir is available in a pill (used following two weeks of intravenous infusion) and also in an implant called Vitrasert. The implant releases medication directly into the eye, so it doesn't cause the side effects experienced with intravenous infusion or with the pill.

Drugs for HIV. The biggest treatment breakthrough is highly active antiretroviral therapy (HAART), a combination of drugs that suppress the human immunodeficiency virus (HIV), also known as the AIDS virus. HAART allows your immune system to recover and fight off infections like CMV retinitis.