IMPACT OF HLA-DR MATCHING ASSESSED BY DNA ANALYSIS IN KIDNEY-TRANSPLANTATION - A ONE-CENTER STUDY

The actual effect of HLA-DR matching in renal transplantation remains controversial. Since DNA analysis has been shown to be more reliable t han serological typing, a re-evaluation of the impact of DR-matching o n graft prognosis is required. In this study, 224 cadaver kidney trans plantations performed in our center were retrospectively matched accor ding to Restriction Fragment Length Polymorphism DR incompatibilities and compared to prospective serological DR-matching. Transplant outcom e was evaluated using graft survival, first rejection onset and reject ion frequency. In 18.8 % individuals, a discrepancy between serology a nd DNA typing for at least one antigen was noted. Serology particularl y failed to type recipients (21.7 %) and 43.2 % of the total missed an tigens were serologically << blank >> or unidentified (<< X >>) allele s. A graft survival rate of 100 % after one year was observed for tran splantations with no DNA DR mismatch (n = 31). Furthermore, there was a definite correlation between DNA matching and (i), the percentage of individuals with one or more than one acute rejection episode (18 % a nd 41.8 % at one year for O incompatibility and pooled 1 and 2 incompa tibilities respectively, p < 0.05) ; (ii), the mean of acute rejection per individual (p < 0.001); and (iii), the rejection onset time (p < 0.01). No correlation between serological matching and the acute rejec tion episodes parameters was noted. Since HLA typing could be performe d in less than 2 hrs using new molecular biology techniques, we conclu de that prospective DNA typing should improve kidney transplantation o utcome in the near future.