Is a DNA PCR Test Useful for Confirmation of HIV Status?

DNA PCR (polymerase chain reaction) tests for HIV are highly accurate and are used to screen for HIV when an antibody test would be unreliable. However, the DNA PCR test is not used as a confirmatory test in the diagnosis of HIV.

Primary Uses

• The primary use of DNA PCR testing is to determine the HIV status of children born to HIV-positive mothers. According to avert.org, HIV-positive women have antibodies to HIV that they can pass on to their baby. Regardless of the newborn's HIV status, he can still carry these antibodies for...Thus, it is unlikely that an antibody test performed on the newborn would be accurate.

  DNA PCR testing is also used to measure the viral load of HIV-positive individuals.

Other Uses

• A DNA PCR test involves treating a sample with reverse transcriptase, which causes HIV present in the sample to begin turning its RNA into DNA (hence the DNA in the name). This process is expensive and complicated, which contributes to the fact that DNA PCR testing is only carried out if it cannot be avoided. Avert.org reports that some private clinics offer DNA PCR testing for adults, but it is very expensive.

Similar Tests

• The DNA PCR test is part of the same category of tests (NAT or nucleic acid amplification tests) as the RNA PCR test. This is the test used to screen blood supplies and other donors because it can produce an accurate result even before a DNA PCR test.

Western Blot

• The main test used for confirming an HIV diagnosis is the Western blot. According to HIV InSite, this test uses electrophoresis to separate certain glycoproteins and proteins that are components of HIV into bands that can accurately confirm the presence of HIV.

Other Confirmatory Tests

• Other, less commonly used confirmatory tests for HIV infection include the indirect immunofluorescent antibody assay, modified Western blot and the line immunoassay. The indirect immunofluorescent antibody assay is useful, according to HIV InSite, in cases where there was an indeterminate result from the Western blot. The modified Western blot has been developed to detect both HIV-1 and HIV-2. The line immunoassay is similar in technique to the Western blot and is widely used in Europe, but according to HIV InSite, it has not been approved for use in the United States.