Influence of test technique on sensitization status of patients on the kidney transplant waiting list

The exquisitely sensitive single antigen bead (SAB) technique was shown to detect human leukocyte antigen (HLA) antibodies in sera of healthy male blood donors. Such false reactions can have an impact on critical decisions, especially with respect to the determination of unacceptable HLA-antigen mismatches in patients awaiting a kidney transplant. We tested pretransplant sera of 534 patients on the kidney waiting list using complement-dependent cytotoxicity (CDC), enzyme-linked immunosorbent assay (ELISA) and SAB in parallel. Evidence of HLA antibodies was obtained in 5% of patients using CDC, 14% using ELISA, and 81% using SAB. Among patients without history of an immunizing event, 77% showed evidence of HLA antibodies in SAB. In contrast 98% of these patients were negative in ELISA and CDC. In patients without an immunizing event, SAB-detected antibodies reacted not always weakly but with mean fluorescence intensity (MFI) values as high as 14 440. High-MFI-value antibodies were found in some of these patients with HLA specificities that are rather common in general population, consideration of which would lead to unjustified exclusion of potential kidney donors. False SAB reactions can be unveiled by testing with additional antibody assays. Denial of donor kidneys to recipients based on HLA-antibody specificities detected exclusively in the SAB assay is not advisable.

Smoking following renal transplantation in Hungary and its possible deleterious effect on renal graft function

Smoking is a known risk factor for kidney damage and also influences graft function following renal transplantation. Because smoking habits following kidney transplantation are not systematically evaluated, we analyzed them in a single center in Hungary. The survey was conducted among 402 randomly selected kidney graft recipients. We assessed smoking-related questions as well as clinical kidney disease and transplantation data. Posttransplantation renal function was analyzed based on serum creatinine values at 1 month and at 3 years after transplantation. In our study 25% (n = 102) of patients continued to smoke after transplantation. Smokers who received grafts displayed a significantly younger age compared with nonsmokers (40.1 +/- 13.4 vs 47.1 +/- 12.7 years; P < .001) independent of underlying kidney disease. Posttransplantation kidney function in smokers did not differ at 1 month after engraftment, but was significantly impaired at 3 years as assessed based on serum creatinine levels: 138.9 +/- 42.4 versus 128.4 +/- 48.5 micromol/L (P < .05). Decrease of renal function correlated with smoking intensity defined in pack-years (r(2) = 0.102; P < .05). Smoking is common following kidney transplantation in Hungary and might represent a risk factor for kidney damage following renal transplantation. Therefore, effective tobacco-dependence treatment is necessary in this patient population.