Monitoring of HLA antobodies in chronic renal failure (CRI) patients on the waiting list for renal transplant in Uruguay

Abstract

Introduction: tests of Human Leucocyte Antigen (HLA), antibodies for patients on the waiting list for renal transplant, are necessary to allocate organs and to define the appropriate immunomodulator treatment that result in the best tranplant survival rates.
Methods: we looked for HLA antobodies in 488 patients on the national waiting list for renal transplant. We defined patients with reactivity > 20% (41 pacients) as immunized, and those with reactivity > 80% (6 patients) as highly immunized, by using the microlymphocitotoxicity technique against a lymphicyte test panel, detecting specificity by ELISA and flow cytometry.
Results and conclusions: we found HLA antibodies class I and class II by ELISA, and identified HLA specificities by flow cytometry: 41 (8.4%) of immunized patients showed HLA antibodies class I and 22 (4.5%) evidenced class II. The most frequently found specificities for these antibodies were : A24, A23, BW6, B44, CW6, CW2, DR8, DR7, DQ2, DQ7.We compared the distribution by age, sex, retransplantation, blood type, previous blood transfusions, time on the waiting list and diagnosis of the immunized population with those non-immunized. We found that in the immunized group most of them are candidates for a second transplant (X2=130,47), have received previous transfusions (X2=119,2) and have been on the waiting list longer(p<0,0001). NO differences were found in the distribution by age, sex or etiological diagnosis of chronic renal failure (CRF), being the non-determined nephropaty and glomerulopathies, the most frequent types. Distribution by blood type showed significant differences: in the immunized group there were more patients belonging to group 0 (X2 =7,9) and less of them belonging to group A (X2 =3,94).