What is AIDS/HIV?
Acquired Immunodeficiency Syndrome (AIDS), a disease which affects the body's ability to fight illness, is caused by the Human Immunodeficiency Virus (HIV). The HIV attacks lymphocytes-white blood cells. T-cells are a kind of lymphocyte, and when the number of T-cells in the body drops below 200 per millilitre, a person is considered to have AIDS.
A person can be infected with HIV but not get the disease until many years later.
Anyone can contract HIV. It is normally transmitted by exchanging bodily fluids when having unprotected sex with an infected person, sharing hypodermic needles, receiving transfusions with infected blood or being born to a mother with HIV.
The incidence of AIDS is changing. More people are contracting the disease. It is becoming more mainstream. New strains are appearing. As the incidence of AIDS increases, so does the incidence of AIDS-related blindness and eye diseases.
AIDS and the Eye
The HIV virus is found in the tears of people infected with AIDS. However, no AIDS cases have ever been reported from tear contact. As a precaution, ophthalmologists are particularly careful when cleaning lenses and instruments which come in contact with tears.
Because HIV attacks the body's immune system, eye infections are common in people with the virus. Incidence of eye infection is high in people with T-cell counts of less than 250. The following outlines a few of the more common conditions:
- Cotton wool spots is the most common eye problems resulting from AIDS. This condition does not affect vision, but does affect the retina - the inner layer of the eye that sends signals to the brain. AIDS can cause small amounts of bleeding and white spots on the retina.
- Cytomegalovirus (CMV), found in 20 - 30% of people with AIDS, causes a serious infection of the retina. Most CMV infections occur in people whose T-cell counts is dangerously low, usually under 40. CMV can harm vision permanently and as yet, there is no cure, just treatment with medication. An ophthalmologist should be contacted immediately if a person notices: floating spots, flashing lights, blind spots or blurred vision. CMV can also cause the retina to separate from the back of the eye. A detached retina will cause serious vision loss. The only method of attachment is surgery.
- Karposi's sarcoma is a kind of tumour that normally appears as purple-red spots. On the eye, it looks like a spot on the white part of the eye or a bump on the eyelid. The tumour grows slowly, does not harm the eye and can be treated with radiation, laser surgery, freezing or operative surgery.
Other eye infections may occur whose symptoms are similar to those of CMV-floaters, flashes or blind spots. Only an ophthalmologist can make a diagnosis and prescribe treatment.
The HIV virus increases the incidence of eye infections. Therefore, regular eye examinations by an ophthalmologist are important. Early diagnosis of these conditions can prevent serious vision loss.
New approaches to the treatment of AIDS-related eye diseases are being developed. For example, implants for treating CMV retinitis can now be placed in the eye that allow medication to be released slowly. Patients will no longer have to make frequent visits to the ophthalmologist for treatment.
© Copyright by the Canadian Ophthalmological Society