HIV, AIDS and the eye
The human immunodeficiency virus (HIV) is a virus that causes a breakdown of the body's immune system.
The immune system fights off illness and infection and is essential to maintaining a healthy body.
Once HIV is present in the body, it attacks important white blood cells in the immune system called lymphocites, or T-cells. T-cells identify and destroy invading organisms in the body. Once attached to the T-cell, HIV replicates and destroys the cell. When the body is deprived of enough T-cells, it can become very sick from infections that a healthy person's immune system would normally fight off, such as colds, flu and other viruses.
When is a person with HIV considered to have AIDS (Acquired Immunodeficiency Syndrome)?
The process of destroying T-cells and replicating HIV may go on for years. This is why many people infected with HIV do not get sick with AIDS until years later. A person is considered to have AIDS when the immune system can no longer keep them healthy.
How does AIDS affect the eye?
Because HIV causes a breakdown of the body's immune system, all areas of the body are susceptible to infection, including the eye. AIDS-related eye problems can include the following:
Cotton woll spots. This is the most common eye problem occurring in people with AIDS. Cotton wool spots are white spots are white spots that form on your retina--the thin layer of light-sensitive tissue lining the back of your eye. The white spots are called "cotton wool spots" because they look like small cotton balls. These spots may cause tiny amounts of bleeding, but they do not normally threaten vision.
CMV retinitis. A more serious eye infection that occurs in about 20 to 30 percent of people with AIDS is CMV retinitis. It is caused by a virus called cytomegalovirus (CMV). It usually occurs in people who have more advanced stages of AIDS in which T-cell count is very low. Symptoms include inflammation of the retina, bleeding and vision loss. If left undiagnosed and untreated, CMV can cause severe vision loss within a few months. CMV retinitis cannot be cured, but progression of the virus can be slowed with medication. A visit to the ophthalmologist is necessary when the person experiences: floating spots or spider-webs, flashing lights, blind spots or blurred vision.
Detached retina. CMV can sometimes caused the retina to pull away or detach from the back of the eye. A detached retina is a serious problem that causes severe vision loss unless treated. Almost all retinal detachments require surgery to put the retina back in its proper position.
Kaposi's sarcoma. This is a rare form of cancer that occurs in AIDS patients. This cancer can cause purple-red lesions to form on the eyelids, or a red, fleshy mass to form on the conjunctiva--the thin, filmy membrane that covers the white part of the eye. Kaposi's sarcoma may look frightening, but it usually does not harm the eye.
How does the body contract HIV?
HIV can be spread by:
- having sex with someone who has the virus;
- sharing hypodermic needles with someone who has the virus;
- receiving transfusions with HIV-infected blood;
- being born to a mother who has HIV;
- receiving a transplant organ infected with the virus.
Blood banks and transplant programs in the United States now test blood and tissue for HIV.