mycophenolic-acid and Kidney-Tubular-Necrosis--Acute

Chronic graft dysfunction is a major cause of return to dialysis. In the majority of cases, it is correlated with histological signs of cellular and/or humoral rejection, the nephrotoxicity of anticalcineurins, or nonspecific lesions of interstitial fibrosis and tubular atrophy. Although the incidence of acute rejection has considerably decreased, renal toxicity of the calcineurin inhibitors remains problematic. In cases of established nephrotoxicity, the use of non-nephrotoxic immunosuppressors such as mycophenolic acid or the proliferation signal inhibitors makes it possible to reduce or even stop the anticalcineurins. In prevention of anticalcineurin nephrotoxicity, many attempts to minimize or wean patients from them have shown that improvement in renal function is only obtained at the cost of an increase in the incidence of acute rejection. This makes it necessary to select patients who may benefit from anticalcineurin-sparing treatment, based on clinical, histological, and biological markers. Finally, long-term follow-up is also fundamental in order to validate the positive impact on renal function of this strategy in terms of graft survival.

Topics: Calcineurin Inhibitors; Cyclosporine; Fibrosis; Follow-Up Studies; Graft Rejection; Graft Survival; Humans; Immunosuppressive Agents; Kidney Transplantation; Kidney Tubular Necrosis, Acute; Mycophenolic Acid; Patient Selection; Primary Graft Dysfunction; Randomized Controlled Trials as Topic; Risk

Acute renal failure (ARF) is a common cause of mortality and morbidity in hospitalized patients. Ischemia is an important cause of ARF, and ARF caused by ischemic injury is referred to as ischemic acute tubular necrosis (ATN). There is growing evidence from models that ischemic ATN is associated with intrarenal inflammation. Consequently, intrarenal inflammation is an attractive target for the development of novel drug therapies for ARF. This review outlines ischemic ATN models, the pathophysiological roles of inflammatory cells such as T and B cells in ischemic ATN models, and effective T and B cell therapeutic reagents.

Topics: Animals; Anti-Inflammatory Agents; B-Lymphocytes; Cells, Cultured; Disease Models, Animal; Drug Evaluation, Preclinical; Gene Expression Profiling; Gene Expression Regulation; Hydroxymethylglutaryl-CoA Reductase Inhibitors; Inflammation; Ischemia; Kidney; Kidney Tubular Necrosis, Acute; Mycophenolic Acid; Oligonucleotide Array Sequence Analysis; T-Lymphocytes

A previous report described the 1-year results of a prospective, randomized trial designed to investigate the optimal combination of immunosuppressants in kidney transplantation. Recipients of first cadaveric kidney allografts were treated with tacrolimus+mycophenolate mofetil (MMF), cyclosporine oral solution (modified) (CsA)+MMF, or tacrolimus+azathioprine (AZA). Results at 1 year revealed that optimal efficacy and safety were achieved with a regimen containing tacrolimus+MMF. The present report describes results at 2 years.. Two hundred twenty-three recipients of first cadaveric kidney allografts were randomized to receive tacrolimus+MMF, CsA+MMF, or tacrolimus+AZA. All regimens contained corticosteroids, and antibody induction was used only in patients who experienced delayed graft function. Patients were followed up for 2 years.. The results at 2 years corroborate and extend the findings of the previous report. Patients randomized to either treatment arm containing tacrolimus experienced improved kidney function. New-onset insulin dependence remained in four, three, and four patients in the tacrolimus+MMF, CsA+MMF, and tacrolimus+AZA treatment arms, respectively. Furthermore, patients with delayed graft function/acute tubular necrosis who were treated with tacrolimus+MMF experienced a 23% increase in allograft survival compared with patients receiving CsA+MMF (P=0.06). Patients randomized to tacrolimus+MMF received significantly lower doses of MMF compared with those administered CsA+MMF.. All three immunosuppressive regi-mens provided excellent safety and efficacy. How-ever, the best results overall were achieved with tacrolimus+MMF. The combination may provide particular benefit to kidney allograft recipients who develop delayed graft function/acute tubular necrosis. Renal function at 2 years was better in the tacrolimus treatment groups compared with the CsA group.

Topics: Administration, Oral; Adolescent; Adult; Antilymphocyte Serum; Azathioprine; Black People; Cadaver; Child; Cross-Over Studies; Cyclosporine; Diabetes Mellitus; Drug Monitoring; Drug Therapy, Combination; Graft Rejection; Graft Survival; Humans; Immunosuppressive Agents; Insulin; Kidney Function Tests; Kidney Transplantation; Kidney Tubular Necrosis, Acute; Mycophenolic Acid; Postoperative Complications; Survival Rate; Tacrolimus; Time Factors; Tissue Donors; United States; White People

Lymphocytes participate in the early pathogenesis of ischemia-reperfusion injury (IRI) in kidney; however, their role during repair is largely unknown. Recent data have shown that Foxp3(+) regulatory T cells (Tregs) traffic into kidney during healing from IRI and directly participate in repair. Since lymphocyte-targeting therapy is currently administered to prevent rejection during recovery from IRI in renal transplants, we hypothesized that mycophenolate mofetil (MMF) would alter Treg trafficking and kidney repair. C57BL/6J and T cell deficient mice underwent unilateral clamping of renal pedicle for 45 min, followed by reperfusion, and were sacrificed at day 10. Mice were treated with saline (C) or MMF (100mg/kg) i.p. daily starting at day 2 until sacrifice (n=5-12/group). MMF worsened kidney tubular damage compared to C at 10 days (cortex and outer medulla: p<0.05) in wild-type mice; tubular apoptotic index was increased in cortex in MMF group as well (p=0.01). MMF reduced the total number of kidney-infiltrating mononuclear cells (p<0.001 versus C) and the percentages of TCRbeta(+)CD4(+) and TCRbeta(+)CD8(+) T cells (p<0.01), but not natural killer (NK), NKT or B lymphocytes. MMF specifically reduced kidney Foxp3(+) Tregs (0.82+/-0.11% versus 1.75+/-0.17%, p<0.05). Tubular proliferative index and tissue levels of basic FGF were increased in MMF group (p<0.05), IL-10 and IL-6 were decreased (p<0.05). To evaluate if MMF effect occurred through non-lymphocytic cells, T cell deficient mice were treated with MMF. Tubular injury in T cell deficient mice was not affected by MMF treatment, though MMF-treated animals had increased VEGF and decreased PDGF-BB protein tissue levels compared to controls (p<0.05). Thus, MMF modifies the structural, epithelial proliferative and inflammatory response during healing, likely through effects on T cells and possibly Tregs. Kidney repair after IRI can be altered by agents that target lymphocytes.

Topics: Animals; Disease Models, Animal; Forkhead Transcription Factors; Immunosuppressive Agents; Kidney; Kidney Tubular Necrosis, Acute; Male; Mice; Mice, Inbred C57BL; Mice, Knockout; Mycophenolic Acid; Reperfusion Injury; T-Lymphocytes, Regulatory

We present a 60-year-old female who underwent living unrelated renal transplantation from her 62-year-old husband. The primary immunosuppression consisted of tacrolimus, mycophenolate mofetil and steroid. We did not recognize any rejection in a histopathological study. The total ischemic time to carry out anastomosis of the two renal arteries was 121 minutes. After hemodialysis 5 times for acute tubular necrosis, her renal function improved. She was discharged on the 33rd postoperative day when her serum cretinine level was 1.0 mg/dl. The graft function was stable at 6 months after transplantation. We discussed living unrelated renal transplantation in the elderly population in Japan.

Topics: Age Factors; Female; Graft Survival; Humans; Immunosuppressive Agents; Kidney Transplantation; Kidney Tubular Necrosis, Acute; Living Donors; Middle Aged; Mycophenolic Acid; Tacrolimus

Among the numeruos adverse side effects of tacrolimus (TAC), de novo thrombotic microangiopathy stands out as an infrecuente but severe complication. Renal dysfunction is the only alteration that should lead to suspicion of thrombotic microangiopathy, because the clinical features of intravascular hemolysis are not always found. The definitive diagnosis can usually be made with kidney biopsy. Patientes with TAC induced thrombotic microangiopathy usually promptly recover after treatment withdrawal or reduction in the dose of TAC and a short course of plasma therapy, but the risk of rejection increases. Switching from TAC to cyclosporine has also been tried with resolution of the hemolysis but thrombotic microangiopathy has been noted with both and this condition may later recur. We present a 29-year-old man who received a kidney-pancreas transplant for end-stage diabetic nephropathy. After initial induction with basiliximab, the immunosuppression consisted of prednisone, tacrolimus and mycophenolate mofetil. Twenty four days posttransplantation his renal function declined with a peak creatine level of 2.35 mg/dl. Laboratory studies showed thrombocytopenia and features of intravascular hemolysis. TAC associated hemolytic uremic syndrome was suspected and drug was immediately stopped and converted to sirolimus. Also he was treated with plasma infusion. The allograft biopsy showed focal glomerular and arteriolar acute thrombosis without evidence of rejection. Our experience demostrate that switching from tacrolimus to sirolimus could be an adecuate strategy for patients who develop FK506-associated de novo thrombotic microangiopathy without increase risk of acute rejection.

Topics: Adult; Antibodies, Monoclonal; Basiliximab; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Drug Therapy, Combination; Duodenostomy; Hemolytic-Uremic Syndrome; Humans; Immunosuppressive Agents; Jejunostomy; Kidney Failure, Chronic; Kidney Transplantation; Kidney Tubular Necrosis, Acute; Male; Mycophenolic Acid; Pancreas Transplantation; Pancreatic Fistula; Plasma; Postoperative Complications; Prednisone; Recombinant Fusion Proteins; Sirolimus; Tacrolimus

Post-ischemia/reperfusion (I/R) damage, accompanied by leukocyte infiltration, is unavoidable in renal transplantation, as is the need for immunosuppressive treatment. Influence of immunosuppressive treatment on post-I/R renal damage, nonalloimmune cellular infiltration, and regeneration is not well studied.. Uninephrectomized inbred LEW rats were submitted to warm renal ischemia of 45 minutes/60 minutes, and received different immunosuppressive regimens: cyclosporine (CsA) 10 mg/kg/day subcutaneously in the neck daily, or mycophenolate mofetil (MMF) 20 mg/kg/day by daily oral gavage. Control animals underwent sham operation (unilateral nephrectomy) with immunosuppressive treatment or ischemia with vehicle administration. In addition the effect of MMF/mycophenolic acid (MPA) on renal tubule cell proliferation in culture was studied with bromodeoxyuridine incorporation.. The post-I/R interstitial cellular infiltration/proliferation consisted mainly of mononuclear leukocytes [first monocytes/macrophages (Mo/MPhi) followed by CD4+ cells]. This mononuclear cell infiltration became apparent 24 hours after injury at the time of acute tubular necrosis, and was most prominent during the phase of regeneration. Severe I/R combined with CsA aggravated morphologic damage and dysfunction, without effect on tubular cell proliferation and tubular regeneration. Early leukocyte infiltration was qualitatively and quantitatively comparable to control animals, yet decreased moderately later in time. In contrast, MMF in combination with severe I/R did not influence initial morphologic damage and dysfunction. Although the initial leukocyte infiltration was comparable to control animals, the subsequent mononuclear cell accumulation, especially CD4 T cells decreased dramatically during MMF treatment. This was concomitant with a decrease of tubular cell proliferation and hence tubular regeneration. Increasing MPA concentrations in renal tubular cell culture caused a significant decrease in total cell number, and an almost arrest of bromodeoxyuridine incorporation, as measurement of cell proliferation.. Immunosuppressive treatment with CsA or MMF affected significantly and in a different manner post-I/R renal morphologic damage, interstitial leukocyte, accumulation and regeneration.

Topics: Animals; Cell Division; Cyclosporine; Immunosuppression Therapy; Immunosuppressive Agents; Kidney; Kidney Tubular Necrosis, Acute; Leukocytes; Male; Mycophenolic Acid; Rats; Rats, Inbred Lew; Regeneration; Renal Circulation; Reperfusion Injury; Severity of Illness Index