title: Association between flow cytometric crossmatching and graft survival in Thai cadaveric-donor kidney transplantation.
abstract: BACKGROUND
  The flow cytometry cross-match (FCXM) technique is a sensitive method and has been reported to predict and protect graft rejection more efficiently than the conventional complement-dependent cytotoxicity cross-match (CDCXM) and the anti-human globulin-complement dependent cytotoxicity (AHG-CDC) methods.
  
  
  METHODS
  We performed retrospective FCXM in 270 cadaveric donor kidney transplant patients with negative CDC and AHG. The correlation between FCXM with graft rejection and graft survival within 1 year to 3 years was analysed.
  
  
  RESULTS
  There were 97 (35.9%) samples with positive FCXM. Only 7 (2.6%) of the 270 samples had evidence of antibody-mediated rejection (AMR) at the first year, which increased to 10 (3.7%) AMR samples after 3 years. Interestingly, there was a significant association between FCXM results with the graft outcome at 1 year (P = 0.046). However, when the association was analysed at 3 years after transplantation, it did not reach statistical significance. FCXM detected concordant positive results in 4 out of 8 samples. These samples had mean fluorescence intensity (MFI) of the donor-specific antibody (DSA) higher than 2,000. The DSA was identified by a single antigen bead.
  
  
  CONCLUSIONS
  Although positive FCXM, particularly for HLA class I, was significantly associated with graft loss from AMR within 1 year of transplantation in this study, there were a lot of FCXM false positives, as high as 35.9%. Additional studies are required to further assess the usefulness of FCXM in Thailand.
authors.affiliation: Histocompatibility and Immunogenetics Laboratory, National Blood Centre, Thai Red Cross Society, Bangkok, Thailand.
authors.forename: Pawinee
authors.initials: P
authors.lastname: Kupatawintu
authors.forename: Araya
authors.initials: A
authors.lastname: Tatawatorn
authors.forename: Nalinee
authors.initials: N
authors.lastname: Premasathian
authors.forename: Yingyos
authors.initials: Y
authors.lastname: Avihingsanon
authors.forename: Asada
authors.initials: A
authors.lastname: Leelahavanichkul
authors.forename: Nattiya
authors.initials: N
authors.lastname: Hirankarn
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D002675:Child, Preschool; D005260:Female; D005434:Flow Cytometry / Q000379:methods*; D006085:Graft Survival; D006650:Histocompatibility Testing / Q000379:methods*; D006801:Humans; D016030:Kidney Transplantation; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies