What tests are done?
Confirming the diagnosis?
A blood test can detect HIV antibodies. (Antibodies are proteins in the blood that attack viruses and other germs. Your body makes antibodies to HIV, although the antibodies are not able to clear HIV from the body.) If you have HIV antibodies (a 'positive' test) it usually means that you are infected with HIV. Occassionally, you can have a positive antibody test without being infected with HIV (a 'false positive' test). Therefore, to confirm the diagnosis, another type of test called the western blot test is usually done. This test detects the presence of HIV particles in your blood.
Note: for several weeks after being first infected, both the antibody test and the western blot test are negative. It takes several weeks, sometimes several months, for you to make antibodies and for either of these tests to become positive. If there is a strong suspicion that you may have recently been infected with HIV and the tests are negative, then the the tests may be repeated a few months later.
Assessing the extent of disease?
If you are confirmed to have HIV then your doctor may do a blood test to check amount of virus in your blood (the viral load) and the number of CD4 T-cells in your blood. These tests may be done from time to time to assess how far the disease has progressed (and the response to treatment).
Tests to diagnose AIDS-related conditions
You may have a range of tests to detect opportunistic infections or other AIDS related conditions, depending on the symptoms that you develop.
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- HIV and AIDS
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- What is the treatment for HIV infection?
- When is treatment with antiretroviral drugs started?
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