title: Clinical validation of a novel diagnostic HIV-2 total nucleic acid qualitative assay using the Abbott m2000 platform: Implications for complementary HIV-2 nucleic acid testing for the CDC 4th generation HIV diagnostic testing algorithm.
abstract: The 2014 CDC 4th generation HIV screening algorithm includes an orthogonal immunoassay to confirm and discriminate HIV-1 and HIV-2 antibodies. Additional nucleic acid testing (NAT) is recommended to resolve indeterminate or undifferentiated HIV seroreactivity. HIV-2 NAT requires a second-line assay to detect HIV-2 total nucleic acid (TNA) in patients' blood cells, as a third of untreated patients have undetectable plasma HIV-2 RNA.
  
  
  
  To validate a qualitative HIV-2 TNA assay using peripheral blood mononuclear cells (PBMC) from HIV-2-infected Senegalese study participants.
  
  
  
  We evaluated the assay precision, sensitivity, specificity, and diagnostic performance of an HIV-2 TNA assay. Matched plasma and PBMC samples were collected from 25 HIV-1, 30 HIV-2, 8 HIV-1/-2 dual-seropositive and 25 HIV seronegative individuals. Diagnostic performance was evaluated by comparing the outcome of the TNA assay to the results obtained by the 4th generation HIV screening and confirmatory immunoassays.
  
  
  
  All PBMC from 30 HIV-2 seropositive participants tested positive for HIV-2 TNA including 23 patients with undetectable plasma RNA. Of the 30 matched plasma specimens, one was HIV non-reactive. Samples from 50 non-HIV-2 infected individuals were confirmed as non-reactive for HIV-2 Ab and negative for HIV-2 TNA. The agreement between HIV-2 TNA and the combined immunoassay results was 98.8% (79/80). Furthermore, HIV-2 TNA was detected in 7 of 8 PBMC specimens from HIV-1/HIV-2 dual-seropositive participants.
  
  
  
  Our TNA assay detected HIV-2 DNA/RNA in PBMC from serologically HIV-2 reactive, HIV indeterminate or HIV undifferentiated individuals with undetectable plasma RNA, and is suitable for confirming HIV-2 infection in the HIV testing algorithm.
authors.affiliation: Department of Laboratory Medicine, Division of Virology, University of Washington, Seattle, United States.
authors.forename: Ming
authors.initials: M
authors.lastname: Chang
authors.affiliation: Department of Laboratory Medicine, Division of Virology, University of Washington, Seattle, United States.
authors.forename: Audrey J S
authors.initials: AJ
authors.lastname: Wong
authors.affiliation: Department of Medicine, Division of Allergy and Infectious Diseases, University of Washington, Seattle, United States.
authors.forename: Dana N
authors.initials: DN
authors.lastname: Raugi
authors.affiliation: Department of Medicine, Division of Allergy and Infectious Diseases, University of Washington, Seattle, United States.
authors.forename: Robert A
authors.initials: RA
authors.lastname: Smith
authors.affiliation: Department of Laboratory Medicine, Division of Virology, University of Washington, Seattle, United States.
authors.forename: Annette M
authors.initials: AM
authors.lastname: Seilie
authors.affiliation: Department of Laboratory Medicine, Division of Virology, University of Washington, Seattle, United States.
authors.forename: Jose P
authors.initials: JP
authors.lastname: Ortega
authors.affiliation: Department of Laboratory Medicine, Division of Virology, University of Washington, Seattle, United States.
authors.forename: Kyle M
authors.initials: KM
authors.lastname: Bogusz
authors.affiliation: Clinique des Maladies Infectieuses Ibrahima Diop Mar - CHNU de Fann, Universite Cheikh Anta Diop de Dakar, Senegal.
authors.forename: Fatima
authors.initials: F
authors.lastname: Sall
authors.affiliation: Clinique des Maladies Infectieuses Ibrahima Diop Mar - CHNU de Fann, Universite Cheikh Anta Diop de Dakar, Senegal.
authors.forename: Selly
authors.initials: S
authors.lastname: Ba
authors.affiliation: Clinique des Maladies Infectieuses Ibrahima Diop Mar - CHNU de Fann, Universite Cheikh Anta Diop de Dakar, Senegal.
authors.forename: Moussa
authors.initials: M
authors.lastname: Seydi
authors.affiliation: Department of Medicine, Division of Allergy and Infectious Diseases, University of Washington, Seattle, United States; Department of Global Health, University of Washington, Seattle, United States.
authors.forename: Geoffrey S
authors.initials: GS
authors.lastname: Gottlieb
authors.affiliation: Department of Laboratory Medicine, Division of Virology, University of Washington, Seattle, United States; Department of Medicine, Division of Allergy and Infectious Diseases, University of Washington, Seattle, United States. Electronic address: bcoombs@u.washington.edu.
authors.forename: Robert W
authors.initials: RW
authors.lastname: Coombs
mesh_terms: D000465:Algorithms; D002487:Centers for Disease Control and Prevention, U.S.; D004279:DNA, Viral / Q000032:analysis*; D015658:HIV Infections / Q000821:virology*; D015498:HIV-2 / Q000235:genetics / Q000302:isolation & purification*; D006801:Humans; D007963:Leukocytes, Mononuclear / Q000821:virology*; D025202:Molecular Diagnostic Techniques / Q000379:methods*; D012367:RNA, Viral / Q000032:analysis*; D012680:Sensitivity and Specificity; D014481:United States
chemical_list: D004279:DNA, Viral; D012367:RNA, Viral
keywords: DNA/RNA; Diagnostic; HIV-2; PCR; Qualitative; Total nucleic acid