Practical diagnostic testing for human immunodeficiency virus

Abstract

Since the discovery of human immunodeficiency virus (HIV) as the causative agent of acquired immunodeficiency syndrome in 1983, there has been a proliferation of diagnostic tests. These assays can be used to detect the presence of HIV antibody, HIV antigen, HIV ribonucleic and deoxyribonucleic acids, and HIV reverse transcriptase. Enzyme-linked immunosorbent assays, Western blot, radioimmunoprecipitation assays, indirect immunofluorescence assays, reverse transcriptase assays, and several molecular hybridization techniques are currently available. Enzyme-linked immunosorbent, Western blot, and indirect immunofluorescence assays for HIV antibody are very sensitive, specific, and adaptable to most laboratories. An enzyme-linked immunosorbent assay for HIV antigen is also readily adaptable to most laboratories and will be commercially available soon. While the other assays are more tedious, they are valuable confirmatory tests and are suitable for reference laboratories. The biohazards of performing HIV testing can be minimized with proper biosafety measures.

Inquérito sorológico para a detecção de anticorpos contra o vírus da Imunodeficiência Humana (VIH) em crianças internadas em enfermaria geral

“…A amostra de sangue foi colhida o mais precocemente possível e o método utilizado foi o ELISA (enzyme linked immunpadsorbent assay) 6,14 , "kit" do laboratório "Abbott". Os exames foram realizados pela Fundação Hemocentro de São Paulo.…”

“…A sensibilidade encontrada em vários estudos variou de 98,1 a 100% 3,6,8,11,14,20 , embora o valor preditivo dependa da prevalên-cia da infecção por este vírus no grupo populacional em estudo. O valor preditivo de seis diferentes "kits" de ELISA foi de 100% em pacientes com SIDA, mas variou de 5 a 100% no grupo de doadores de sangue 24 .…”

“…Em outro estudo, o valor preditivo negativo variou de 100,0% na população geral a 76,9% nos membros de grupos de risco 24,30 . Nas crianças, principalmente naquelas menores de 15 meses de idade, o resultado dos testes que pesquisam imunoglobulinas da classe IgG contra o vírus deve ser analisado com cuidado, uma vez que, quando positivo, pode representar, tão somente, transferência passiva das mesmas durante a gestação 1,14,15,23,27,29 .…”

Immunoserology of infectious diseases

“…Although not yet commercially available, a Western blot (immunoblot) assay to confirm questionable antibody reactions is being used at major medical centers located in endemic areas (12 (43). EIA tests for human Tlymphotrophic virus type antibodies are used to screen the blood supply to minimize the possiblity of transfusionacquired exposure to this virus which has been etiologically associated with adult T-cell leukemia or lymphoma (66 newly acquired infections, this method will not be helpful to monitor patients, since antigenuria in most systems tested can persist for months to years after resolution of the infectious process.…”

Comparative Evaluation of an Immunofluorescent Antibody Test, Enzyme Immunoassay and Western Blot for the Detection of HIV-1 Antibody

“…A reliable confirmatory assay must be used to retest all EIA-positive specimens because specificity is less than 100% and, moreover, because of the serious implication of an HIV-I antibody-positive EIA result. Serolog ical assays shown to be effective for confirm ing positive results include the immunofluor escent antibody (IFA) test, radioimmuno précipitation assay (RIPA) and Western blot ( WB) test [2,[10][11][12][13]. Currently, the only FDA approved confirmatory assay is the WB test.…”