title: Reduction of the HIV seroconversion window period and false positive rate by using ADVIA Centaur HIV antigen/antibody combo assay.
abstract: BACKGROUND
  Early diagnosis of HIV infection reduces morbidity and mortality. Fourth-generation HIV detection assays are more sensitive because they can detect p24 antigen as well as anti-HIV antibodies. In this study, we evaluated the performance of a new fourth-generation ADVIA Centaur HIV antigen/antibody combo (CHIV) assay (Siemens Healthcare Diagnostics Inc., USA) for early detection of HIV infection and reduction of false positive rate.
  
  
  METHODS
  Four seroconversion panels were included. The third-generation ADVIA Centaur HIV 1/O/2 enhanced (EHIV) assay (Siemens Healthcare Diagnostics Inc., USA) and fourth-generation CHIV assay were used to test each panel for HIV infection. The presence of antigen was confirmed using HIV p24 antigen assay. To evaluate false-positivity and specificity, 54 HIV false-positive and HIV-negative serum samples from 100 hospitalized patients and 600 healthy subjects were included.
  
  
  RESULTS
  COMPARED TO THE EHIV ASSAY, THE CHIV ASSAY HAD A SHORTER WINDOW FOR THREE OF THE SEROCONVERSION PANELS: a difference of 10 days and two bleeds in one panel, and 4 days and one bleed in the other two panels. Only 34 of the 54 (63%) samples known to yield false-positive results by EHIV assay had repeatedly yielded reactive results in the CHIV assay. One of the 600 healthy subjects had a false-positive result with the CHIV assay; thus, the specificity was 99.85% (699/700). CHIV accurately determined the reactive results for the HIV-confirmed serum samples from known HIV patients and Korea Food & Drug Administration (KFDA) panels.
  
  
  CONCLUSIONS
  The new fourth-generation ADVIA Centaur HIV assay is a sensitive and specific assay that shortens the serological window period and allows early diagnosis of HIV infection.
authors.affiliation: Department of Laboratory Medicine and Genetics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Kyunghoon
authors.initials: K
authors.lastname: Lee
authors.forename: Hyung-Doo
authors.initials: HD
authors.lastname: Park
authors.forename: Eun-Suk
authors.initials: ES
authors.lastname: Kang
mesh_terms: D005189:False Positive Reactions; D005260:Female; D015483:HIV Antibodies / Q000097:blood* / Q000276:immunology; D016655:HIV Core Protein p24 / Q000097:blood* / Q000276:immunology; D006679:HIV Seropositivity / Q000175:diagnosis*; D006801:Humans; D008297:Male; D011247:Pregnancy; D011933:Reagent Kits, Diagnostic; D056910:Republic of Korea; D012680:Sensitivity and Specificity; D013997:Time Factors
chemical_list: D015483:HIV Antibodies; D016655:HIV Core Protein p24; D011933:Reagent Kits, Diagnostic
keywords: HIV; HIV Combo assay; Seroconversion; Specificity; Window period