AIDS, HIV, and The Eye
What is AIDS?
AIDS stands for Acquired Immune Deficiency Syndrome. It is a disease of the body’s immune system. In a healthy individual, the immune system helps to fight off illness such as an infection.
What is HIV?
AIDS is caused by a virus called the Human Immunodeficiency Virus (HIV), which attacks many cells in the body. HIV especially attacks white blood cells called lymphocytes. A special kind of lymphocyte is known as the T-cell.
You can be infected with HIV but not get sick with AIDS until many years later. You are considered to have AIDS when:
- Your T-cells drop below a certain level (under 200 T-cells per cubic millimeter) in a blood test.
- Your immune system is no longer able to keep you healthy.
It’s very important to know if you are HIV positive at any early stage. If you get treatment before you are sick, you can stay well longer.
How Can You Catch HIV and AIDS?
Anyone can catch HIV. It can be spread by:
- Having sex with an infected person;
- Sharing hypodermic needles;
- Being born to a mother who has HIV;
- Receiving blood transfusions with infected blood.
Blood banks in the Unites States now test blood for HIV. It is very rare to get AIDS from blood transfusions.
What about HIV in tears?
While the HIV virus can be found in tears of people with AIDS, no case of AIDS has ever been reported from tear contact. Ophthalmologists are especially careful in cleaning their lenses and instruments which come in contact with tears.
How does AIDS affect the eye?
Cotton-wool spots - The most common eye problem from AIDS doesn’t threaten vision. Your eye has an inner layer called the retina which sends images to the brain and helps you see. Sometimes AIDS can cause white spots in the retina with tiny amounts of bleeding. These white spots are called "cotton-wool spots" because they look like small cotton balls.
A serious infection of the retina is caused by CMV, the cytomegalovirus. About 20 - 30% of people with AIDS develop CMV. Most infections happen when the number of T-cells gets dangerously low.
HIV Infection and CMV Retinitis:
- Cytomegalovirus (CMV) retinitis is the most common sight-threatening eye disease in HIV patients with AIDS.
- Left untreated, this disease will rapidly lead to total blindness.
- Treatment is available for CMV retinitis, and is very effective in slowing or stopping progression of the disease, and therefore in saving your sight.
Symptoms of CMV retinitis include:
- Blurry or decreased vision affecting the center of your vision or your peripheral (side) vision can be a symptom. Peripheral vision loss is more common than central vision loss, but both are possible.
- Increasing floaters (small specks in your vision that move around when you move your eye) are a common symptom of CMV retinitis.
- A dark spot in your vision (that moves with eye movement) can be a sign of CMV retinitis.
Who gets CMV retinitis?
Not all HIV infected people with AIDS get CMV retinitis. Currently, there is no way to predict who will or won’t get the disease.
HIV infected people at risk for CMV retinitis include:
- People whose T-cell count (CD4) is 50 or less (About 1 in 3 (~33%) of people in this group develop CMV retinitis.)
- People who have been treated with HAART (highly active antiretroviral treatment) may have a lower risk of CMV retinitis. Estimates of the risk in patients on this therapy are ~5%.
- People with CMV disease somewhere else in their body (lungs, GI tract, brain, liver, etc.) are at risk for this eye disease.
- Rarely, people whose T-cell count is less than 100 can be affected.
What do I do if I have symptoms of CMV retinitis?
If you have symptoms of CMV retinitis, contact your ophthalmologist. If you have CMV retinitis, your ophthalmologist will explain to you all treatment options that will help save your sight.
If you have HIV, you should have a baseline examination by an ophthalmologist. Regular screening examinations, perhaps as often as every three to six months, may be recommended if your T-cell count becomes low. These issues should be discussed with your ophthalmologist and your internist.
Detached retina - Sometimes CMV causes the retina to separate from the back of the eye. A detached retina can cause serious vision loss. The only way to reattach the retina is with eye surgery.
Kaposi’s sarcoma - Kaposi’s sarcoma (KS) is a kind of tumor that looks like purple-red spots. In the eyes, it can look like a bump on the eyelid or a spot on the white part of the eye. KS can look frightening, but it grows slowly and does not harm the eye.
What are the treatments for AIDS eye problems?
Drugs such as Ganciclovir® (DHPG) and Foscarnet® are commonly used to fight CMV infections. Such drugs don’t kill CMV, but slow its progression. You must go to your ophthalmologist for regular eye exams while being treated for CMV to be sure the CMV infection is responding to the medicine. Recent advances in anti-CMV therapy include a sustained-release Ganciclovir implant. A minor surgical procedure is performed to place an implant into the vitreous cavity of the eye, and the anti-CMV medication Ganciclovir® is slowly released by this implant, which lasts an average of eight months. The implant is more effective than intravenous therapy in treating new cases of CMV retinitis. However, oral anti-CMV medications are needed to prevent CMV infection from developing elsewhere in the body.
Another medication, Fomvirsen (ISIS2922), will soon become available for use intravitreally. Injection into the eye is performed, initially every week, then every two weeks, to stop the advance of CMV retinitis. This medication has been shown to be highly effective in patients who have been unresponsive to all other regimens.
If only one eye is infected, you may be able to protect the other eye by taking anti-CMV medicines. New treatments are continuously being developed. If necessary, Kaposi’s sarcoma can be treated with radiation, laser surgery, freezing, or conventional surgery.
There are other eye infections with AIDS whose symptoms may be the same as CMV: flashes, floaters, or blind spots. But each disease has its own treatment and only your ophthalmologist can tell which you need.
Regular eye exams are important for HIV infection.
If your T-cell count is very low, you are more likely to get a serious eye infection. If you experience changes in your vision, you need to see your ophthalmologist promptly.