Cytomegalovirus Retinitis (CMV Retinitis)
CMV retinitis is a serious eye infection of the retina, the light-sensing nerve layer that lines the back of the eye. It is a significant threat to people with weak immune systems, such as people with HIV and AIDS, newborns, the elderly, people taking chemotherapy, and recipients of organ transplants. About 20 to 30 percent of people with AIDS develop CMV retinitis.
Infection with cytomegalovirus, one of the herpes viruses, is extremely common and does not pose a problem for someone with a strong immune system. But when immunity is weak, the CMV can reactivate and spread to the retina through the bloodstream.
First signs of CMV retinitis are loss of peripheral vision or a blind spot which can progress to loss of central vision. Without treatment or improvement in the immune system, CMV retinitis destroys the retina and damages the optic nerve, which results in blindness.
Injection of one or two drugs daily is the current treatment for CMV retinitis. A promising new therapy involves placing a small implant inside the eye that slowly releases the anti-CMV drug ganciclovir.
Warning signs that should be examined by an ophthalmologist immediately are floating spots or spiderwebs, flashing lights, blind spots or blurred vision. Recurrence of CMV retinitis is common so monthly check-ups with an ophthalmologist are important.
Toxoplasmosis is a common parasitic infection. When contracted by a pregnant woman, toxoplasmosis can pose serious risks to the unborn baby. Simple precautions can reduce the chance of infection.
Pregnant women should avoid handling litter boxes and eating raw meat because the parasite may originate in cat feces or undercooked meat. If acquired during the first trimester of pregnancy, the infection can be devastating to an infant.
Toxoplasmosis affects the retina, the light-sensitive cells lining the back of the eye. Both eyes are usually involved. If the infection settles in the macula, the area of the retina responsible for central vision, good vision is lost forever.
When toxoplasmosis heals, it leaves a scar. The infection may recur years later, sometimes near the previously infected area. Swelling that fights the infection may cause floating spots in one’s vision, red, painful eyes, and poor vision.
Treating toxoplasmosis with oral medications can be very effective. Pyrimethamine and sulfa drugs are the classic antibiotics although some doctors add or substitute clindamycin. Occasionally steroids, laser, or freezing (cryotherapy) treatments are prescribed.
Screening tests can identify women of childbearing age who are at risk of passing the infection to an unborn child.
Birdshot Retinochoroidopathy (BR)
Birdshot retinochoroidopathy (BR) is a rare, inflammatory condition of the retina and choroid, the layer of blood vessels under the retina. BR usually occurs in Caucasian women over the age of forty.
The cause of BR is unknown. It usually affects both eyes. Symptoms are poor vision, night blindness, and disturbance of color vision. Pain is rare.
Fluorescein angiography, a test for evaluating the retina and choroid, detects BR’s characteristic cream-colored spots, similar in appearance to the splattered pattern of birdshot from a shotgun.
BR is a chronic disease that flares up and then goes into remission. Although some people eventually lose vision, others maintain or recover good vision.
If you have been diagnosed with birdshot retinochoroidopathy, it is important to see your ophthalmologist regularly.