Robert W. Steiner

Evaluation of Intravenous Immunoglobulin as an Agent to Lower Allosensitization and Improve Transplantation in Highly Sensitized Adult Patients with End-Stage Renal Disease: Report of the NIH IG02 Trial

Reported are the reduction of anti-HLA antibody levels and improvement of transplant rates by intravenous immunoglobulin (IVIG) in a randomized, double-blind, placebo-controlled clinical trial. Between 1997 and 2000, a total of 101 adult patients with ESRD who were highly sensitized to HLA antigens (panel reactive antibody [PRA] > or =50% monthly for 3 mo) enrolled onto an NIH-sponsored trial (IG02). Patients received IVIG or placebo. Subjects received IVIG 2 g/kg monthly for 4 mo or an equivalent volume of placebo with additional infusions at 12 and 24 mo after entry if not transplanted. If transplanted, additional infusions were given monthly for 4 mo. Baseline PRA levels were similar in both groups. However, IVIG significantly reduced PRA levels in study subjects compared with placebo. Sixteen IVIG patients (35%) and eight placebo patients (17%) were transplanted. Rejection episodes occurred in 9 of 17 IVIG and 1 of 10 placebo subjects. Seven graft failures occurred (four IVIG, three placebo) among adherent patients with similar 2-yr graft survival rates (80% IVIG, 75% placebo). With a median follow-up of 2 yr after transplant, the viable transplants functioned normally with a mean +/- SEM serum creatinine of 1.68 +/- 0.28 for IVIG versus 1.28 +/- 0.13 mg/dl for placebo. Adverse events rates were similar in both groups. We conclude that IVIG is better than placebo in reducing anti-HLA antibody levels and improving transplantation rates in highly sensitized patients with ESRD. Transplant rates for highly sensitized patients with ESRD awaiting kidney transplants are improved with IVIG therapy.

Posttransplant therapy using high-dose human immunoglobulin (intravenous gammaglobulin) to control acute humoral rejection in renal and cardiac allograft recipients and potential mechanism of action.

BACKGROUND Intravenous gammaglobulin (i.v.IG) contains anti-idiotypic antibodies that are potent inhibitors of HLA-specific alloantibodies in vitro and in vivo. In addition, highly HLA-allosensitized patients awaiting transplantation can have HLA alloantibody levels reduced dramatically by i.v.IG infusions, and subsequent transplantation can be accomplished successfully with a crossmatch-negative, histoincompatible organ. METHODS In this study, we investigated the possible use of i.v.IG to reduce donor-specific anti-HLA alloantibodies arising after transplantation and its efficacy in treating antibody-mediated allograft rejection (AR) episodes. We present data on 10 patients with severe allograft rejection, four of whom developed AR episodes associated with high levels of donor-specific anti-HLA alloantibodies. RESULTS Most patients showed rapid improvements in AR episodes, with resolution noted within 2-5 days after i.v.IG infusions in all patients. i.v.IG treatment also rapidly reduced donor-specific anti-HLA alloantibody levels after i.v.IG infusion. All AR episodes were reversed. Freedom from recurrent rejection episodes was seen in 9 of 10 patients, some with up to 5 years of follow-up. Results of protein G column fractionation studies from two patients suggest that the potential mechanism by which i.v.IG induces in vivo suppression is a sequence of events leading from initial inhibition due to passive transfer of IgG to eventual active induction of an IgM or IgG blocking antibody in the recipient. CONCLUSION I.v.IG appears to be an effective therapy to control posttransplant AR episodes in heart and kidney transplant recipients, including patients who have had no success with conventional therapies. Vascular rejection episodes associated with development of donor-specific cytotoxic antibodies appears to be particularly responsive to i.v.IG therapy.

Results of the double-blind, randomized, multicenter, phase III clinical trial of thymoglobulin versus Atgam in the treatment of acute graft rejection episodes after renal transplantation

BACKGROUND Thymoglobulin, a rabbit anti-human thymocyte globulin, was compared with Atgam, a horse anti-human thymocyte globulin for the treatment of acute rejection after renal transplantation. METHODS A multicenter, double-blind, randomized trial with enrollment stratification based on standardized histology (Banff grading) was conducted. Subjects received 7-14 days of Thymoglobulin (1.5 mg/kg/ day) or Atgam (15 mg/kg/day). The primary end point was rejection reversal (return of serum creatinine level to or below the day 0 baseline value). RESULTS A total of 163 patients were enrolled at 25 transplant centers in the United States. No differences in demographics or transplant characteristics were noted. Intent-to-treat analysis demonstrated that Thymoglobulin had a higher rejection reversal rate than Atgam (88% versus 76%, P=0.027, primary end point). Day 30 graft survival rates (Thymoglobulin 94% and Atgam 90%, P=0.17), day 30 serum creatinine levels as a percentage of baseline (Thymoglobulin 72% and Atgam 80%; P=0.43), and improvement in posttreatment biopsy results (Thymoglobulin 65% and Atgam 50%; P=0.15) were not statistically different. T-cell depletion was maintained more effectively with Thymoglobulin than Atgam both at the end of therapy (P=0.001) and at day 30 (P=0.016). Recurrent rejection, at 90 days after therapy, occurred less frequently with Thymoglobulin (17%) versus Atgam (36%) (P=0.011). A similar incidence of adverse events, post-therapy infections, and 1-year patient and graft survival rates were observed with both treatments. CONCLUSIONS Thymoglobulin was found to be superior to Atgam in reversing acute rejection and preventing recurrent rejection after therapy in renal transplant recipients.

Agalsidase Alfa and Kidney Dysfunction in Fabry Disease

In male patients with Fabry disease, an X-linked disorder of glycosphingolipid metabolism caused by deficient activity of the lysosomal enzyme alpha-galactosidase A, kidney dysfunction becomes apparent by the third decade of life and invariably progresses to ESRD without treatment. Here, we summarize the effects of agalsidase alfa on kidney function from three prospective, randomized, placebo-controlled trials and their open-label extension studies involving 108 adult male patients. The mean baseline GFR among 54 nonhyperfiltrating patients (measured GFR <135 ml/min per 1.73 m(2)) treated with placebo was 85.4 +/- 29.6 ml/min per 1.73 m(2); during 6 mo of placebo, the mean annualized rate of change in GFR was -7.0 +/- 32.9 ml/min per 1.73 m(2). Among 85 nonhyperfiltrating patients treated with agalsidase alfa, the annualized rate of change was -2.9 +/- 8.7 ml/min per 1.73 m(2). Treatment with agalsidase alfa did not affect proteinuria. Multivariate analysis revealed that GFR and proteinuria category (< 1 or > or = 1 g/d) at baseline significantly predicted the rate of decline of GFR during treatment. This summary represents the largest group of male patients who had Fabry disease and for whom the effects of enzyme replacement therapy on kidney function have been studied. These data suggest that agalsidase alfa may stabilize kidney function in these patients.

Consensus conference on best practices in live kidney donation: Recommendations to optimize education, access, and care

Live donor kidney transplantation is the best treatment option for most patients with late‐stage chronic kidney disease; however, the rate of living kidney donation has declined in the United States. A consensus conference was held June 5–6, 2014 to identify best practices and knowledge gaps pertaining to live donor kidney transplantation and living kidney donation. Transplant professionals, patients, and other key stakeholders discussed processes for educating transplant candidates and potential living donors about living kidney donation; efficiencies in the living donor evaluation process; disparities in living donation; and financial and systemic barriers to living donation. We summarize the consensus recommendations for best practices in these educational and clinical domains, future research priorities, and possible public policy initiatives to remove barriers to living kidney donation.

Living kidney donor follow-up: State-of-the-art and future directions, conference summary and recommendations

In light of continued uncertainty regarding postkidney donation medical, psychosocial and socioeconomic outcomes for traditional living donors and especially for donors meeting more relaxed acceptance criteria, a meeting was held in September 2010 to (1) review limitations of existing data on outcomes of living kidney donors; (2) assess and define the need for long‐term follow‐up of living kidney donors; (3) identify the potential system requirements, infrastructure and costs of long‐term follow‐up for living kidney donor outcomes in the United States and (4) explore practical options for future development and funding of United States living kidney donor data collection, metrics and endpoints. Conference participants included prior kidney donors, physicians, surgeons, medical ethicists, social scientists, donor coordinators, social workers, independent donor advocates and representatives of payer organizations and the federal government. The findings and recommendations generated at this meeting are presented.

‘Normal for Now’ or ‘At Future Risk’: A Double Standard for Selecting Young and Older Living Kidney Donors

Transplant centers medically evaluate potential living kidney donors in part to determine their baseline remaining lifetime risk for end stage renal disease (ESRD). If baseline risk is increased by the presence of a risk factor for ESRD, donation is often refused. However, as only about 13% of ESRD occurs in the general population by age 44, a normal medical evaluation cannot be expected to significantly reduce the 7% lifetime risk for a ‘normal’ 25‐year‐old black donor or the 2–3% risk for a similar white donor. About half of newly diagnosed ESRD in the United States occurs by age 65, and about half of that is from diabetic nephropathy, which takes about 25 years to develop. Therefore, the remaining baseline lifetime risk for ESRD is significantly lower in the normal, nondiabetic 55‐year‐old donor candidate. Some older donors with an isolated medical abnormality such as mild hypertension will be at lower or about the same overall baseline lifetime risk for ESRD as are young ‘normal’ donor candidates. Transplant centers use a ‘normal for now’ standard for accepting young donors, in place of the long‐term risk estimates that must guide selection of all donors.

Estimating Risks of De Novo Kidney Diseases After Living Kidney Donation

De novo postdonation renal diseases, such as glomerulonephritis or diabetic nephropathy, are infrequent and distinct from the loss of GFR at donation that all living kidney donors experience. Medical findings that increase risks of disease (e.g. microscopic hematuria, borderline hemoglobin A1C) often prompt donor refusal by centers. These risk factors are part of more comprehensive risks of low GFR and end‐stage renal disease (ESRD) from kidney diseases in the general population that are equally relevant. Such data profile the ages of onset, rates of progression, prevalence and severity of loss of GFR from generically characterized kidney diseases. Kidney diseases typically begin in middle age and take decades to reach ESRD, at a median age of 64. Diabetes produces about half of yearly ESRD and even more lifetime near‐ESRD. Such data predict that (1) 10‐ to 15‐year studies will not capture the lifetime risks of postdonation ESRD; (2) normal young donors are at demonstrably higher risk than normal older candidates; (3) low normal predonation GFRs become risk factors for ESRD when kidney diseases arise and (4) donor nephrectomy always increases individual risk. Such population‐based risk data apply to all donor candidates and should be used to make acceptance standards and counseling more uniform and defensible.

Effect of daily oral vitamin D and calcium therapy, hypophosphatemia, and endogenous 1-25 dihydroxycholecalciferol on parathyroid hormone and phosphate wasting in renal transplant recipients.

Ten stable, normocalcemic renal transplant patients with good allograft function, hyperparathyroidism, and variable hypophosphatemia were treated for 2 to 9 months with oral calcium carbonate and replacement doses of vitamin D analogues. Parathyroid hormone levels (PTH) and renal phosphate wasting were not autonomous or fixed but decreased with therapy. Although serum 1–25(OH)2D3 levels could be shown to rise appropriately during oral vitamin D therapy and fall afterwards, a separate study in a larger group of patients showed no effect of elevated parathyroid hormone or hypophosphatemia to increase endogenous 1–25(OH)2D3 levels. Some 42% of patients with elevated carboxyterminal PTH, had elevated N-terminal PTH, which was closely associated with more severe phosphate wasting. Aggressive oral calcium and vitamin D supplementation in certain normocalcemic renal transplant patients may decrease endogenous PTH levels, improve hypophosphatemia, and provide a physiologic increase in levels of 1–25(OH)2D3.

Abdominal Catastrophes and Other Unusual Events in Continuous Ambulatory Peritoneal Dialysis Patients

Primary bacterial peritonitis and catheter-associated infections compose the large majority of abdominal events in continuous ambulatory peritoneal dialysis (CAPD) patients. Yet occasionally primary pathology involving the abdominal viscera develops, and surgery is frequently considered. The early manifestations of intraabdominal inflammation or bleeding in patients undergoing CAPD depend on the pathological process, its access to the peritoneal cavity, and whether generalized bacterial peritonitis supervenes to obscure helpful physical findings. Clear dialysate is not a reliable sign that major pathology is absent, nor does initial stabilization of the clinical course with antibiotic therapy uniformly indicate that surgery will not be necessary. Polymicrobial peritonitis may develop in cholecystitis, pancreatitis, or from a colonic source, the latter featuring more bacterial species and more gram-negative and anaerobic organisms. A history directed at progression of symptoms and sites of abdominal discomfort and an examination for deep local tenderness and bowel incarcerated in an abdominal wall hernia are essential. Measurement of dialysate amylase and Gram stain of dialysate for food fibers may be helpful. Imaging techniques such as abdominal radiographs for dilated bowel or free subdiaphragmatic air, ultrasonography of the gallbladder or pancreas, computed tomographic (CT) scanning of the lower abdomen, and water-soluble contrast colonic studies may help identify the pathologic process. Special studies such as these should be considered early in the course of suspected unusual abdominal events in patients on CAPD.