title: An epidemiologic study to determine the prevalence of the HLA-B*5701 allele among HIV-positive patients in Europe.
abstract: OBJECTIVE
  HLA-B*5701 is a major histocompatibility complex class I allele associated with an immunologically-mediated hypersensitivity reaction to abacavir. The objectives of this study were to evaluate HLA-B*5701 prevalence among European, HIV-1-infected patients and to compare the local and central laboratory screening results.
  
  
  METHODS
  Data were combined from six multicentre, prospective studies involving 10 European countries in which HIV-1-infected patients (irrespective of treatment experience or previous HLA-B*5701 screening), >or=18 years of age, were evaluated for HLA-B*5701 carriage, determined by the central and local laboratory methods.
  
  
  RESULTS
  A total of 9720 patients from 272 centres were included in the analysis. The overall estimate of HLA-B*5701 prevalence in Europe was 4.98%, with country-specific estimates ranging from 1.53 to 7.75%. HLA-B*5701 prevalence was highest in the self-reported white population (6.49%) and lowest in the black population (0.39%). Local laboratory results had a high specificity (99.9%) and sensitivity (99.2%) when compared with the central laboratory results.
  
  
  CONCLUSIONS
  This study supports data from previous studies regarding the prevalence of HLA-B*5701 in the HIV population and the variation of HLA-B*5701 prevalence between different racial groups. The high specificity and sensitivity of local laboratory results, suggests that clinicians can be confident in using local laboratories for pretreatment HLA-B*5701 screening. However, it is essential that local laboratories participate in HLA-B*5701-specific quality assurance programs to maintain 100% sensitivity. In HIV-infected patients, pretreatment HLA-B*5701 screening may allow more informed decisions regarding abacavir use and has the potential to significantly reduce the frequency of abacavir-related hypersensitivity reactions and costs associated with managing these reactions.
authors.affiliation: Barts and The London NHS Trust, London, UK. orkin.chloe@bartsandthelondon.nhs.uk
authors.forename: Chloe
authors.initials: C
authors.lastname: Orkin
authors.forename: Jianmin
authors.initials: J
authors.lastname: Wang
authors.forename: Colm
authors.initials: C
authors.lastname: Bergin
authors.forename: Jean-Michel
authors.initials: JM
authors.lastname: Molina
authors.forename: Adriano
authors.initials: A
authors.lastname: Lazzarin
authors.forename: Matthias
authors.initials: M
authors.lastname: Cavassini
authors.forename: Stefan
authors.initials: S
authors.lastname: Esser
authors.forename: Juan-Luis
authors.initials: JL
authors.lastname: Gómez Sirvent
authors.forename: Helen
authors.initials: H
authors.lastname: Pearce
mesh_terms: D000328:Adult; D000483:Alleles; D005060:Europe; D005260:Female; D015658:HIV Infections / Q000453:epidemiology / Q000235:genetics*; D006679:HIV Seropositivity; D015235:HLA-B Antigens / Q000235:genetics*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D015995:Prevalence; D011446:Prospective Studies; D012680:Sensitivity and Specificity
chemical_list: D015235:HLA-B Antigens; C484830:HLA-B*57:01 antigen