title: High seroprevalence of anti-HTLV-I/II antibodies among solid organ donors necessitates confirmatory testing.
abstract: BACKGROUND
  Human T-cell lymphotrophic virus (HTLV) type I has been linked to adult T-cell leukemia/lymphoma (ATL) and HTLV-I associated myelopathy (HAM). Transmission of HTLV by blood and organ transplantation has been documented, with some infections leading to clinical disease. Organ donors are tested for anti-HTLV antibodies and donor suitability is determined primarily by results from enzyme immunoassays (EIA). Confirmatory testing is not routinely performed, and the number of false positive organ donors is unknown.
  
  
  METHODS
  In order to investigate the contemporary seroprevalence of anti-HTLV I/II antibodies among solid organ donors and determine the number of false positive samples, we tested 1,408 specimens from prospective organ donors in 2002 and 2003. All specimens were tested for anti-HTLV antibodies by a commercial EIA. Repeatedly reactive specimens underwent confirmatory testing using a commercial Western blot.
  
  
  RESULTS
  There were 22 repeatedly EIA reactive donor specimens (1.56%). Five specimens did not undergo further testing because of case shutdown or insufficient sample quantity. HTLV I/II western blot confirmed six positives, whereas five were negative and six were indeterminate. The majority of confirmed specimens were positive for antibodies to HTLV-II.
  
  
  CONCLUSIONS
  Our data shows that 29% of initially reactive specimens were false positives. With the increasing demand for organs, the unnecessary rejection of organs that are falsely positive for HTLV antibodies becomes of tremendous importance and stresses the need for timely confirmatory testing for HTLV.
authors.affiliation: National Institute of Transplantation, Los Angeles, CA 90057, USA. marek@usc.edu
authors.forename: Marek J
authors.initials: MJ
authors.lastname: Nowicki
authors.forename: Lea
authors.initials: L
authors.lastname: Matsuoka
authors.forename: Dem
authors.initials: D
authors.lastname: Brucal
authors.forename: Claudia
authors.initials: C
authors.lastname: Chinchilla
authors.forename: Thomas
authors.initials: T
authors.lastname: Mone
authors.forename: Rick
authors.initials: R
authors.lastname: Selby
authors.forename: Robert
authors.initials: R
authors.lastname: Mendez
mesh_terms: D000328:Adult; D015153:Blotting, Western; D005260:Female; D015481:HTLV-I Antibodies / Q000097:blood*; D015482:HTLV-II Antibodies / Q000097:blood*; D006801:Humans; D008297:Male; D008875:Middle Aged; D016036:Seroepidemiologic Studies; D014019:Tissue Donors
chemical_list: D015481:HTLV-I Antibodies; D015482:HTLV-II Antibodies