Acute graft pyelonephritis: a potential cause of acute rejection in renal transplant.

Acute graft pyelonephritis is a common complication in renal transplant recipients. The consequences of this complication on kidney allograft survival remain controversial. Bacterial infection is likely to activate the immune system, potentially leading to acute or chronic rejection. Here, we report for the first time two documented cases of acute rejection occurring shortly after acute graft pyelonephritis, suggesting that pyelonephritis can initiate acute rejection. The immunologic process leading to the alloimmune response is discussed. These reports suggest that acute rejection should be questioned in case of atypical graft outcome in the context of acute graft pyelonephritis.

Long-term results of a prospective randomized study comparing two immunosuppressive regimens, one with and one without CsA, in low-risk renal transplant recipients.

Due to the nephrotoxicity of cyclosporin A (CsA), its benefit on long-term graft survival remains controversial, especially in low-risk patients. Here we report the 12-year results of a calcineurin-inhibitor-free regimen. One hundred and seventeen low-risk kidney recipients were prospectively randomized to maintenance therapy with either a combination of azathioprine and prednisone (group NoCsA, n=58), or with cyclosporine, azathioprine, and prednisone (group CsA, n=59). Both groups received induction therapy with anti-lymphocyte globulins (ALG). Twelve-year patient survival was 75% and 82.5% in the CsA and NoCsA groups, respectively [ P= not significant (NS)]. Twelve-year graft survival was 59% and 56% ( P=NS) in the CsA and NoCsA groups, respectively (NS). Transplant rejection rates were similar in both groups. Mean serum creatinine levels after 10 years were 161 and 136 micromol/l in the CsA and NoCsA groups, respectively. Rejection-free patients of the CsA group had poorer renal function (168 micromol/l) than those of the NoCsA group (121 micromol/l; P=0.0060). We concluded that a 12-year graft survival of 56% and a graft half-life of 15 years can be achieved without the primary use of a calcineurin inhibitor in low-risk patients receiving ALG. Patients treated with CsA had poorer graft function at 12 years.

Long-term kidney graft survival across a positive historic but negative current sensitized cross-match.

BACKGROUND: The sensitive cross-match (XM) techniques that have been introduced for clinical transplantation can detect anti-donor immune reactivity despite a negative standard National Institute of Health (NIH) cross-match. One of them uses anti-kappa human light chain globulins (AHG). But there is some discussion about the clinical consequences of a positive AHG-XM in the historical sera that became negative in the sera collected just before the transplantation (pretransplant sera). This study was intended to assess the risk of kidney graft failure associated with a positive historic but negative pretransplant AHG-XM in allosensitized patients having a negative historic NIH-XM. METHODS: This retrospective study includes 90 consecutive renal transplants in immunized patients performed at one center between 1985 and 1991. All of the patients had negative historical and pretransplant standard NIH lymphocytotoxic cross-matches and received the same immunosuppressive regimen. The AHG-XMs were done retrospectively using peak historic and sera collected on the day of the transplantation. RESULTS: The AHG cross-match (AHG-XM) was positive in 17 patients, although the standard NIH cross-match was negative. Fourteen of them had a positive historical but negative pretransplant AHG-XM. The actuarial graft survival in this group of 14 patients was 100% at 1 year and 78% at 9 years compared with 90 and 67%, respectively, in patients with negative historical AHG-XM. In addition, the number of rejection episodes per patient as well as renal function at 1, 2, and 5 years were similar in the two groups. IgG anti-donor HLA class I accounted for the XM positivity in 12 of the 14 patients; most rapidly lost all antibody reactivity by NIH technique in an average time of 8 months before the transplantation. In conclusion, this study suggests that transplant patients having a negative historic NIH-XM but a positive historic AHG-XM may not be at high risk of graft failure especially if there is a well-documented sera history showing a marked decrease in PRA level before transplantation and a negative pretransplant AHG-XM.