 |
NetWellness provides the highest quality health information and education services created and evaluated by faculty of our partner universities.
Saturday, July 5, 2008
|
|
|
NetWellness provides the highest quality health information and education services created and evaluated by faculty of our partner universities.
Saturday, July 5, 2008
|
Acquired Immunodeficiency Syndrome (AIDS) is a disease that results from a human immunodeficiency virus (HIV) infection. AIDS occurs during the final stage of HIV infection and causes the body's immune system to fail. Individuals with AIDS often die of other diseases such as pneumonia because their weakened immune systems can no longer fight infections.
Human Immunodeficiency Virus (HIV) is an infection that invades the cells of the body's immune system and gradually destroys them over time. The last and most deadly stage of HIV infection is AIDS.
AIDS test, HIV (Human Immunodeficiency Virus) test, and AIDS screening test are common names used to refer to an HIV screening test. Enzyme linked immunospecific assay (ELISA) is a form of enzyme immunoassay (EIA) that is the most common method used to screen people for HIV infection. The ELISA test detects antibodies to the HIV virus. The body produces these antibodies (proteins that circulate in the blood) in an attempt to destroy the invading virus. The ELISA and other EIA tests are used for screening purposes because they are very sensitive and can detect even small amounts of antibodies. In order for the ELISA test to detect the HIV virus, an individual must be infected long enough to produce antibodies. This process could take a period of weeks to months. The ELISA and other EIA screening tests have the potential to produce a false alarm for HIV infection known as a false-positive result. As a result, the tests are repeated a second time. If the results are negative, no further tests are done.
If a positive result comes back after the initial screening test has been repeated, a more accurate (but also more time consuming and expensive) test is performed called Western Blot. The purpose of this test is to confirm an HIV infection previously detected by the ELISA or EIA test. The Western blot (WB) is the most c ommonly used confirmatory test in the U.S. and it detects 96% of HIV infections. The WB test is most often performed in a hospital or reference laboratory and the results are ready usually between 2 and 14 days. This procedure involves drawing a sample of blood from a vein in your arm. The blood is then sent to a lab where it is analyzed for the presence of HIV antibodies (proteins that circulate in the blood) in the blood serum (a fluid found when clotting blood is left standing long enough for the clot to shrink).
If the Western Blot test has confirmed the presence of the HIV virus, other tests can be performed to measure the amount of HIV virus in the body. One such test is the branched DNA Assay test. The purpose of this test is to establish the stage of HIV infection, determine when to start giving medications, and to monitor the progress of therapy. The procedure involves taking a sample of blood drawn from a vein in the arm and measuring the amount of viral particles per milliliter (mL) of blood plasma (a clear liquid substance that transports the platelets in the blood and waste products to the kidneys, liver, and spleen) This test looks for the HIV virus in an individual's DNA and is now being used to verify that blood being given for transfusion is free of the HIV virus. The branch DNA assay test is often referred to as a "viral load" test. One recent advance in HIV testing is home testing for HIV. Some individuals may prefer this method because the sample for testing can be collected in the privacy of one's home. The only home test that is FDA approved is the Home Access Express HIV-1 Test System, manufactured by Home Access Health Corporation. A blood sample obtained at home can be mailed to a laboratory where it is examined by medical professionals. The test costs approximately $50.00 and uses a personal identification number so that the results are anonymous.
A positive diagnosis of HIV may produce anxiety, stress, and depression. Therefore, if you have been diagnosed with HIV, it is recommended that you seek counseling from a trained medical professional. Most facilities that perform HIV testing have counseling services readily available at little or no cost. It is also important to know that the law prohibits the disclosure of tests results to anyone but the individual being tested. Most states also have what is known as an informed-consent law, which makes it illegal to test a blood sample for HIV infection without consent.
This article is a NetWellness exclusive. 
Last Reviewed: Aug 09, 2000
|
Amadeo Pesce, PhD Professor Emeritus Department of Pathology and Laboratory Medicine College of Medicine University of Cincinnati |
|
|
Please note: only your personal physician or other health professional you consult can best advise you on matters of your health based on your medical history, your family medical history, your medication history, and how information from any of these databases may apply to you. Neither University of Cincinnati (NetWellness) nor any party involved in creating, producing or delivering this web site shall be liable for any damages arising out of access to or use of this web site, or any errors or omissions in the content thereof. (More) |