Anti-HIV antibody testing: procedures and precautions.

Prudent use of screening tests for infection with human immunodeficiency virus (HIV) and interpretation of test results require an understanding of the body's immune response to HIV infection, the serologic assays currently available, and the problems associated with false-positive and false-negative test results. The methodologies of the enzyme immunoassay (enzyme-linked immunosorbent assay [ELISA]) and the Western blot assay are presented, and efficacies of these tests are evaluated. Tests for the detection of anti-HIV antibodies that are, at this time, primarily restricted to research use but that show promise for adaptation to screening (such as the ELISA with recombinant antigen) also are discussed, as is the alternative of testing for HIV antigens or HIV-specific DNA. From a personal perspective, any test for HIV infection is accompanied by certain benefits and risks. These can be discussed with the patient in the framework of pretest and posttest counseling.