Pre transplant PRA (penal reactive antibody) and DSA (donor specific antibody) screening status and outcome after renal transplantation

Abstract

BackgroundForty six renal transplant recipients were evaluated by pre-transplant PRA screening (Class I and Class II) by luminex assay (Lifecodes Life-screen Deluxe (LMX) by Gen-Probe). PRA screening results and DSA positivity were correlated with development of rejection episodes. Single Antigen (SA) solid phase antibody assay (One-lambda) was also correlated with rejection episodes. MethodAll the 46 kidney transplant recipients were complement dependant cytotoxicity (CDC) crossmatch negative at room, warm, and cold temperatures pretransplant. PRA and Donor Specific Antibody (DSA) (Lifecode) assays were done by luminex. SA antibody assay was done by One-lambda kit by luminex system. ResultsAll the 46 kidney transplant recipients had PRA screening done on luminex platform. They were divided in to two groups: Group (Gr)-I (PRA negative) n = 30, 65% of patients studied. Group (Gr)-II (PRA Positive) n = 16, 35% of patients. In PRA negative group, only 3 of 30 patients (10%) were DSA positive; one against class I and two recipients had antibody against class-II HLA antigens. Of the PRA negative group, 16 patients received kidney transplantation. Induction with Basiliximab (BSA) was given in 9 and by anti-thymocyte globulin (ATG) in 7 recipients. Two of 16 (12.5%) PRA negative patients developed acute rejection (AR) episodes. Of PRA positive group (16 recipients) only one was DSA positive (6.2%) of PRA positive group, only 6 were transplanted (4 were given induction with BSA, two recipients got ATG induction. Two recipients out of 6 (33%) from PRA positive group who were transplanted had acute rejection (one had evidence of acute cellular rejection and another had glomerulitis on allograft histology) despite being CDC cross match negative. PRA positivity was associated with increased acute rejection episodes. On SA antibody assay, three recipients showed antibody against donor class-II antigens by single bead Luminex assay. All these three patients with single antigen DSA positivity developed acute rejection. All these three recipients showed no donor specific antibody pre transplant and CDC cross match against donor was also negative at the time of kidney transplantation. ConclusionThere was no correlation between DSA positivity and PRA screen positivity. PRA screen negative group had lesser no of acute rejection episodes. PRA positive patients had higher acute rejection episodes despite no evidence of DSA. Single Antigen (SA) antibody positivity was associated with increased episodes of acute rejection (AR).