HIV genotypic resistance
At a Glance
Why Get Tested?
If you have been diagnosed with HIV and are receiving anti-viral therapy that is not working effectively
When to Get Tested?
If your HIV viral load values rise steadily even though you are receiving anti-viral therapy
Sample Required?
A blood sample drawn from a vein in your arm
The Test Sample
What is being tested?
In genotypic resistance testing, the genetic code of the particular strain of HIV a patient has is checked to see if there any genetic mutations that are known to cause drug resistance. HIV is said to be resistant to an antiviral medication if it keeps multiplying while a person is taking the drug. Changes (mutations) in the virus cause resistance. HIV mutates almost every time a new copy of the virus is made, but not every mutation causes resistance. Antiviral drugs control most types of HIV, however, a strain of virus containing a mutation that is resistant to a drug will multiply and become the most common form of the virus in the body (as all the other forms are destroyed by the drug). For certain drugs, single mutations of a gene increase resistance to high levels. For other drugs, a combination of mutations is required for resistance to form.
How is the sample collected for testing?
The test is performed on a sample of blood drawn from a needle placed in your arm.
The Test
Common Questions
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Article Sources
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