Impact of pretransplant exposure to allosensitization factors generating HLA antibodies in the Luminex era.

AIM: To identify the frequency of exposure to sensitizing factors and evaluate the risk ascribable to each sensitizing factor generating HLAabs measured by Luminex.

METHODS: This is a retrospective cohort study that included 502 transplanted patients and 51 patients on the waiting list for a deceased donor graft. Patients were divided into 4 groups according to the %PRA: 0%, 1 to 19%, 20 to 49% and ≥50%. The OR attributable to each sensitizing factor or combination were calculated.

RESULTS: Of the total 553 subjects, 53.5% were male, with an average age 35.42±12.96years. 69.1% were exposed to one or more sensitizing factors; 44.8% had %PRA class I≥1 and 38.9% had %PRA class II≥1. Independently or combined, sensitizing factors persist as a risk factor for the development of a %PRA >1%, >20% or >50%. After multivariate analysis, the three sensitizing factors remained significantly associated to HLAab development.

CONCLUSIONS: In spite of using a most sensitive technique such as Luminex to measure the %PRA, a clear association persists between exposure to sensitizing factors and a high %PRA. The risk increases after exposure to more than one sensitizing factor.