title: Comparative evaluation of the Bio-Rad Geenius HIV-1/2 Confirmatory Assay and the Bio-Rad Multispot HIV-1/2 Rapid Test as an alternative differentiation assay for CLSI M53 algorithm-I.
abstract: BACKGROUND
  The CLSI-M53-A, Criteria for Laboratory Testing and Diagnosis of Human Immunodeficiency Virus (HIV) Infection; Approved Guideline includes an algorithm in which samples that are reactive on a 4th generation EIA screen proceed to a supplemental assay that is able to confirm and differentiate between antibodies to HIV-1 and HIV-2. The recently CE-marked Bio-Rad Geenius HIV-1/2 Confirmatory Assay was evaluated as an alternative to the FDA-approved Bio-Rad Multispot HIV-1/HIV-2 Rapid Test which has been previously validated for use in this new algorithm.
  
  
  METHODS
  This study used reference samples submitted to the Canadian - NLHRS and samples from commercial sources. Data was tabulated in 2×2 tables for statistical analysis; sensitivity, specificity, predictive values, kappa and likelihood ratios.
  
  
  RESULTS
  The overall performance of the Geenius and Multispot was very high; sensitivity (100%, 100%), specificity (96.3%, 99.1%), positive (45.3, 181) and negative (0, 0) likelihood ratios respectively, high kappa (0.96) and low bias index (0.0068). The ability to differentiate HIV-1 (99.2%, 100%) and HIV-2 (98.1%, 98.1%) Ab was also very high.
  
  
  CONCLUSIONS
  The Bio-Rad Geenius HIV-1/2 Confirmatory Assay is a suitable alternative to the validated Multispot for use in the second stage of CLSI M53 algorithm-I. The Geenius has additional features including traceability and sample and cassette barcoding that improve the quality management/assurance of HIV testing. It is anticipated that the CLSI M53 guideline and assays such as the Geenius will reduce the number of indeterminate test results previously associated with the HIV-1 WB and improve the ability to differentiate HIV-2 infections.
authors.affiliation: National Laboratory for HIV Reference Services, Public Health Agency of Canada, Ottawa, ON K1A 0K9, Canada.
authors.forename: L
authors.initials: L
authors.lastname: Malloch
authors.affiliation: National Laboratory for HIV Reference Services, Public Health Agency of Canada, Ottawa, ON K1A 0K9, Canada.
authors.forename: K
authors.initials: K
authors.lastname: Kadivar
authors.affiliation: Saskatchewan Disease Control Laboratory, Regina, SK S4S 0A4, Canada.
authors.forename: J
authors.initials: J
authors.lastname: Putz
authors.affiliation: Saskatchewan Disease Control Laboratory, Regina, SK S4S 0A4, Canada.
authors.forename: P N
authors.initials: PN
authors.lastname: Levett
authors.affiliation: Alberta Provincial Laboratory for Public Health, Edmonton Site, AB T6G 2J2, Canada.
authors.forename: J
authors.initials: J
authors.lastname: Tang
authors.affiliation: Department of Pathology and Laboratory Medicine, Capital District Health Authority, Halifax, NS B3H 1V8, Canada.
authors.forename: T F
authors.initials: TF
authors.lastname: Hatchette
authors.affiliation: Cadham Provincial Laboratory, Winnipeg, MB R3C 3Y1, Canada.
authors.forename: K
authors.initials: K
authors.lastname: Kadkhoda
authors.affiliation: National Laboratory for HIV Reference Services, Public Health Agency of Canada, Ottawa, ON K1A 0K9, Canada.
authors.forename: D
authors.initials: D
authors.lastname: Ng
authors.affiliation: National Laboratory for HIV Reference Services, Public Health Agency of Canada, Ottawa, ON K1A 0K9, Canada.
authors.forename: J
authors.initials: J
authors.lastname: Ho
authors.affiliation: National Laboratory for HIV Reference Services, Public Health Agency of Canada, Ottawa, ON K1A 0K9, Canada. Electronic address: john.kim@phac-aspc.gc.ca.
authors.forename: J
authors.initials: J
authors.lastname: Kim
mesh_terms: D000465:Algorithms; D019411:Clinical Laboratory Techniques / Q000379:methods*; D003955:Diagnostic Tests, Routine / Q000379:methods*; D015483:HIV Antibodies / Q000097:blood*; D015658:HIV Infections / Q000175:diagnosis* / Q000821:virology*; D015497:HIV-1 / Q000145:classification* / Q000276:immunology; D015498:HIV-2 / Q000145:classification* / Q000276:immunology; D006801:Humans; D007118:Immunoassay / Q000379:methods; D011237:Predictive Value of Tests; D012680:Sensitivity and Specificity; D014773:Virology / Q000379:methods
chemical_list: D015483:HIV Antibodies
keywords: APHL; Ab; Ag; Algorithm; Association of Public Health Laboratories; CDC; CE; CI; CLSI; CRF; Centers for Disease Control and Prevention; Clinical and Laboratory Standards Institute; Ctrl; DNA; DPP; Dual Path Platform; EIA; European Conformity; FDA; Food and Drug Administration; GS; Geenius; HIV; HIV-1; HIV-2; IFA; IND; INNO-LIA HIV I/II Score; Inno-LIA; M53; Multispot; N/A; NAT; NEG; NLHRS; NPV; National Laboratory for HIV Reference Services; PCR; PCS; POS; PPV; RNA; SK; Saskatchewan; UNT; WB; Western blot; antibody; antigen; circulating recombinant form; confidence interval; control; deoxyribonucleic acid; enzyme immunoassay; genetic systems; glycoprotein; gp; human immunodeficiency virus; immunofluorescence assay; indeterminate; k; kappa; negative; negative predictive value; not applicable; nucleic acid testing; p; polymerase chain reaction; positive; positive predictive value; procedural control spot; protein; r-gp; recombinant glycoprotein; ribonucleic acid; sp; synthetic peptide; untypeable; w; weighted for prevalence