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Lab Update 20 - Adult HIV Diagnosis

Jul 01, 2020 | Microbiology

Infectious Diseases HIV

The standard approach to the laboratory diagnosis of HIV infection in adults and children older than 18 months is to detect the presence of HIV-specific antibodies in a blood specimen, usually by means of an enzyme-linked immunosorbent assay (ELISA). Screening HIV ELISA tests are designed to be extremely sensitive tests so that the negative predictive value of the tests is almost 100% (excluding those with window period infections). Most commercially available HIV ELISA assays detect HIV antibodies and the p24 antigen simultaneously, thereby reducing the window period of these tests. The downside to having a sensitive screening test is that false positive results may occur in a small percentage of positive specimens, which is why internatio...

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