HLA-Matched Donor-Recipient Combinations and Kidney Transplant Probabilities in a Specific Colombian Population

Introduction: In Colombia, despite the fact that kidney transplants are the most common type of transplant surgery, a great number of transplanted patients do not achieve the desired Human Leucocyte Antigen (HLA) compatibility. HLA compatibility plays an important role in graft survival; patients with matched-HLA have a lower chance of graft-versus-host disease and graft rejection. Objective: To determine the probability of finding an HLA-matched donor-recipient pairs according to HLA−A, −B and −DRB1 frequencies in a specific Colombian population. Materials and methods: The study included a total of 484 unrelated individuals (61 donors and 423 recipients) from the HLA registry. HLA alleles were determined by polymerase chain reaction sequence with specific indicators. Results: HLA-A*02, -A*24, -B*35 and -DRB1*04 alleles showed the highest minimum allele frequency (>10%). In addition, HLA-A*24-B*35-DRB1*04 was the most frequent extended haplotype in both donors and recipients (7.38% and 6.76%, respectively). Our experimental evidence showed that the maximum chance of finding at least one HLA allele-matched kidney is 20.3% for a patient with the most frequent extended haplotype, whereas for patients with rare or non-common haplotypes this probability is rather unlikely. Discussion: In terms of probability, the chance of finding an HLA matched kidney donor/recipients in our region is low. This is due, at least in part, to the higher number of alleles and a the lower donation rate. Therefore, to define the HLA profile of a population is important for establishing transplantation programs and alternative strategies in the kidney donation and allocation processes.