title: Abacavir hypersensitivity reaction in primary HIV infection.
abstract: OBJECTIVE
  To evaluate risk factors associated with the abacavir hypersensitivity reaction during primary HIV infection (PHI).
  
  
  METHODS
  Acute HIV Infection and Early Disease Research Program protocol (AIEDRP) AI-02-001 provided antiretroviral therapy including abacavir. This retrospective analysis evaluated variables potentially associated with hypersensitivity in the cohort enrolled in AI-02-001 at the University of Washington Primary Infection Clinic.
  
  
  METHODS
  Cases of suspected hypersensitivity were identified prospectively and reviewed retrospectively using a standardized case definition. Controls were the remaining cohort without hypersensitivity. Univariate analyses were performed by linear logistic regression.
  
  
  RESULTS
  Nine (18%) of 50 individuals treated with abacavir developed suspected hypersensitivity. Two of nine cases and no controls were HLA-B5701 positive. When antiretroviral medications were started, cases had lower mean CD8 T-cell percentage and plasma HIV RNA value. After 2 weeks on abacavir, cases had a lower mean HIV RNA value and a trend towards greater decrease in RNA. Cases began abacavir a median of 103 days after HIV acquisition compared to 48 days for controls. There was no significant in vitro abacavir-specific lymphoproliferation or IFN-gamma production in peripheral blood mononuclear cells from individuals following the suspected hypersensitivity reaction.
  
  
  CONCLUSIONS
  Abacavir use during PHI may be associated with increased risk of hypersensitivity. As in chronic infection, HLA-B5701 is associated with the abacavir hypersensitivity reaction in PHI. Although levels of CD8 T cells and HIV RNA may be risk factors for hypersensitivity, the observed association may be due to correlation with HLA-B5701. The interesting temporal association of hypersensitivity with initiation of abacavir later in PHI merits future investigation.
authors.affiliation: Division of Allergy and Infectious Diseases, University of Washington, Harborview Medical Center, 325 Ninth Avenue, Seattle, WA 98104, USA. jstekler@u.washington.edu
authors.forename: Joanne
authors.initials: J
authors.lastname: Stekler
authors.forename: Janine
authors.initials: J
authors.lastname: Maenza
authors.forename: Claire
authors.initials: C
authors.lastname: Stevens
authors.forename: Sarah
authors.initials: S
authors.lastname: Holte
authors.forename: Uma
authors.initials: U
authors.lastname: Malhotra
authors.forename: M Juliana
authors.initials: MJ
authors.lastname: McElrath
authors.forename: Lawrence
authors.initials: L
authors.lastname: Corey
authors.forename: Ann C
authors.initials: AC
authors.lastname: Collier
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D015224:Dideoxynucleosides / Q000009:adverse effects* / Q000627:therapeutic use; D004342:Drug Hypersensitivity; D005434:Flow Cytometry; D015658:HIV Infections / Q000188:drug therapy* / Q000276:immunology; D015497:HIV-1; D015235:HLA-B Antigens / Q000276:immunology; D006801:Humans; D016015:Logistic Models; D008297:Male; D011446:Prospective Studies; D012189:Retrospective Studies; D012306:Risk; D018709:Statistics, Nonparametric; D000099227:Abacavir
chemical_list: D015224:Dideoxynucleosides; D015235:HLA-B Antigens; D000099227:Abacavir; C103707:HLA-B57 antigen