title: Re-testing and misclassification of HIV-2 and HIV-1&2 dually reactive patients among the HIV-2 cohort of the West African Database to evaluate AIDS collaboration.
abstract: BACKGROUND
  West Africa is characterized by the circulation of HIV-1 and HIV-2. The laboratory diagnosis of these two infections as well as the choice of a first-line antiretroviral therapy (ART) is challenging, considering the limited access to second-line regimens. This study aimed at confirming the classification of HIV-2 and HIV-1&2 dually reactive patients followed up in the HIV-2 cohort of the West African Database to evaluate AIDS collaboration.
  
  
  METHODS
  A cross-sectional survey was conducted from March to December 2012 in Burkina Faso, Côte d'Ivoire and Mali among patients classified as HIV-2 or HIV-1&2 dually reactive according to the national HIV testing algorithms. A 5-ml blood sample was collected from each patient and tested in a single reference laboratory in Côte d'Ivoire (CeDReS, Abidjan) with two immuno-enzymatic tests: ImmunoCombII® (HIV-1&2 ImmunoComb BiSpot - Alere) and an in-house ELISA test, approved by the French National AIDS and hepatitis Research Agency (ANRS).
  
  
  RESULTS
  A total of 547 patients were included; 57% of them were initially classified as HIV-2 and 43% as HIV-1&2 dually reactive. Half of the patients had CD4≥500 cells/mm(3) and 68.6% were on ART. Of the 312 patients initially classified as HIV-2, 267 (85.7%) were confirmed as HIV-2 with ImmunoCombII® and in-house ELISA while 16 (5.1%) and 9 (2.9%) were reclassified as HIV-1 and HIV-1&2, respectively (Kappa=0.69; p<0.001). Among the 235 patients initially classified as HIV-1&2 dually reactive, only 54 (23.0%) were confirmed as dually reactive with ImmunoCombII® and in-house ELISA, while 103 (43.8%) and 33 (14.0%) were reclassified as HIV-1 and HIV-2 mono-infected, respectively (kappa= 0.70; p<0.001). Overall, 300 samples (54.8%) were concordantly classified as HIV-2, 63 (11.5%) as HIV-1&2 dually reactive and 119 (21.8%) as HIV-1 (kappa=0.79; p<0.001). The two tests gave discordant results for 65 samples (11.9%).
  
  
  CONCLUSIONS
  Patients with HIV-2 mono-infection are correctly discriminated by the national algorithms used in West African countries. HIV-1&2 dually reactive patients should be systematically investigated, with a standardized algorithm using more accurate tests, before initiating ART as at least 4 out of 10 of them could initiate an effective first-line ART for HIV-1 and optimize their second-line treatment options.
authors.affiliation: Centre INSERM U897-Epidémiologie-Biostatistique, ISPED, Université de Bordeaux, Bordeaux, France; Inserm U897, ISPED, Université de Bordeaux, Bordeaux, France; Programme PACCI, Site de recherche ANRS, Abidjan, Côte d'Ivoire; boris.tchounga@yahoo.fr.
authors.forename: Boris K
authors.initials: BK
authors.lastname: Tchounga
authors.affiliation: Centre de Diagnostic et de Recherche sur le SIDA et les Affections Opportunistes, CHU de Treichville, Abidjan, Côte d'Ivoire.
authors.forename: Andre
authors.initials: A
authors.lastname: Inwoley
authors.affiliation: Programme PACCI, Site de recherche ANRS, Abidjan, Côte d'Ivoire; Service des Maladies Infectieuses et Tropicales, CHU de Treichville, Abidjan, Côte d'Ivoire.
authors.forename: Patrick A
authors.initials: PA
authors.lastname: Coffie
authors.affiliation: Centre de Prise en Charge des Personnes vivant avec le VIH, Hôpital du Point G, Bamako, Mali.
authors.forename: Daouda
authors.initials: D
authors.lastname: Minta
authors.affiliation: Programme PACCI, Site de recherche ANRS, Abidjan, Côte d'Ivoire; Centre de Prise en Charge de Recherche et de Formation, CePReF-Aconda-VS, Abidjan, Côte d'Ivoire.
authors.forename: Eugene
authors.initials: E
authors.lastname: Messou
authors.affiliation: Hôpital de Jour, Service des Maladies Infectieuses et Tropicales, CHU Souro Sanou, Bobo Dioulasso, Burkina Faso.
authors.forename: Guillaume
authors.initials: G
authors.lastname: Bado
authors.affiliation: Programme PACCI, Site de recherche ANRS, Abidjan, Côte d'Ivoire; Centre Médical de Suivi de Donneurs de Sang/CNTS/PRIMO-CI, Abidjan, Côte d'Ivoire.
authors.forename: Albert
authors.initials: A
authors.lastname: Minga
authors.affiliation: Centre Intégré de Recherches Biocliniques d'Abidjan CIRBA, Abidjan, Côte d'Ivoire.
authors.forename: Denise
authors.initials: D
authors.lastname: Hawerlander
authors.affiliation: Laboratoire de Bactériologie-Virologie, Département GC&BA-ESP/UCAD, CHU A Le Dantec, Dakar, Sénégal.
authors.forename: Coumba
authors.initials: C
authors.lastname: Kane
authors.affiliation: Programme PACCI, Site de recherche ANRS, Abidjan, Côte d'Ivoire; Service des Maladies Infectieuses et Tropicales, CHU de Treichville, Abidjan, Côte d'Ivoire.
authors.forename: Serge P
authors.initials: SP
authors.lastname: Eholie
authors.affiliation: Centre INSERM U897-Epidémiologie-Biostatistique, ISPED, Université de Bordeaux, Bordeaux, France; Inserm U897, ISPED, Université de Bordeaux, Bordeaux, France.
authors.forename: François
authors.initials: F
authors.lastname: Dabis
authors.affiliation: Centre INSERM U897-Epidémiologie-Biostatistique, ISPED, Université de Bordeaux, Bordeaux, France; Inserm U897, ISPED, Université de Bordeaux, Bordeaux, France; Programme PACCI, Site de recherche ANRS, Abidjan, Côte d'Ivoire; Département des Sciences Fondamentales et Santé Publique, Université de Lomé, Lomé-Togo.
authors.forename: Didier K
authors.initials: DK
authors.lastname: Ekouevi
mesh_terms: D000163:Acquired Immunodeficiency Syndrome / Q000175:diagnosis* / Q000821:virology*; D000328:Adult; D002050:Burkina Faso; D060085:Coinfection / Q000175:diagnosis / Q000821:virology; D007560:Cote d'Ivoire; D003430:Cross-Sectional Studies; D003951:Diagnostic Errors / Q000706:statistics & numerical data*; D005260:Female; D015483:HIV Antibodies / Q000097:blood*; D015497:HIV-1 / Q000276:immunology* / Q000302:isolation & purification; D015498:HIV-2 / Q000276:immunology* / Q000302:isolation & purification; D006801:Humans; D008297:Male; D008302:Mali; D008875:Middle Aged; D012698:Serologic Tests / Q000379:methods
chemical_list: D015483:HIV Antibodies
keywords: HIV-1&2 dually reactive; HIV-2; West Africa; classification; testing