K. Koshino

Evaluation of renal allograft fibrosis by transient elastography (Fibro Scan).

BACKGROUND Chronic allograft injury (CAI) is one of the most important factors for graft failure after renal transplantation. Protocol biopsy is the most valuable tool for revealing subclinical renal allograft failure. Transient elastography (TE) is a noninvasive technique that has shown utility for the assessment of hepatic and renal fibrosis. This study sought to evaluate whether TE was a viable and effective method for the assessment of renal allograft failure. PATIENTS AND METHODS Thirty-five patients underwent TE by Fibro Scan (Echosense, Paris, France). Biopsies were performed in 27 patients, allowing classification according to Banff chronic changes in the interstitium grade 0, grade 1 or grade 2. RESULTS Measurement of parenchymal stiffness was successful in 31 of 35 patients (91%). Stiffness was significantly correlated with interstitial fibrosis (P < .05) and inversely related with estimated glomerular filtration rate (eGFR; P < .05). Stiffness values of patients with eGFR > 50 mL/min were lower than those of patients with eGFR < 50 mL/min (P < .05). Patients classed as CAI Banff grade 0 had significantly less parenchymal stiffness than patients with Banff grade 1 or grade 2 CAI (P < .05). Parenchymal stiffness measured by TE reflected interstitial fibrosis in renal allograft. CONCLUSION Assessment of parenchymal renal allograft stiffness by TE was effective for identifying patients with CAI who may subsequently benefit from biopsy and modification of the immunosuppressive regimen. Assessment of parenchymal renal allograft stiffness can be effective for identifying patients with CAI. TE has the potential to reduce the number of renal allograft biopsies required for accurate assessment of CAI.

Outcome of tonsillectomy for recurrent IgA nephropathy after kidney transplantation

Since 2007, we have performed tonsillectomies for patients with recurrent immunoglobulin A nephropathy (IgAN) after kidney transplantation. Seven patients with primary IgAN showed biopsy‐proven recurrent IgAN after living‐donor kidney transplantation. They had persistent proteinuria or hematuria for an average of 40.3 months, and tonsillectomy was performed, on average, 75.6 months after kidney transplantation. In six patients with observation periods of more than one yr, good remission of urinary findings was observed after tonsillectomy. We classified the seven patients into three types of renal injury based on histological findings: severe, moderate, and mild. Two patients classified with severe renal injury at the time of tonsillectomy had other problems, such as refractory hypertension and bilateral sinusitis. They followed a rapidly progressive clinical course. One case already had moderate histological renal injury. He demonstrated prompt amelioration of urinary findings after tonsillectomy but immediate deviation from remission of proteinuria and hematuria. In the four cases presenting mild renal injury at tonsillectomy, the improved urinary findings and serum creatinine value after tonsillectomy have persisted. In conclusion, tonsillectomy may be a favorable treatment for cases of mild‐grade IgAN. However, other treatments such as antihypertensive agents and diet therapy may be necessary in other grades.

The Excellent Outcomes of ABO-Incompatible Kidney Transplantation With High Titer (>×2048) Using Anti-CD20 and Anti-CD25 Antibody Without Splenectomy: Two Case Reports

BACKGROUND Due to the shortage of deceased donors, we have expanded the indications for living-donor kidney transplantation (LKT) to include ABO-incompatible (ABO-i) individuals. However, which patients with high-titer anti-blood-group antibody can be transplanted successfully is unclear. METHODS Since 2009 we have performed 2 high-titer ABO-i spousal LKT using anti-CD20 and anti-CD25 monoclonal antibody without splenectomy. In both cases, anti-type A antibody was 2048-fold before antibody removal. The immunosuppressive regimen consisted of 2 doses of anti-CD20 antibody (200 mg/body, day -14 to day -7), mycophenolate mofetil (1000 mg), prednisolone (10 mg starting from day -14), calcineurin inhibitor (cyclosporine [7 mg/kg] or tacrolimus [0.2 mg/kg] starting from day -7), and 2 doses of anti-CD25 antibody (20 mg/body, days 0 and 4). Antibody removal by plasmapheresis was performed up to 4 times before LKT according to the antibody titer. The posttransplantation regimen consisted of mycophenolate mofetil or mizoribine as antimetabolite. A protocol biopsy was performed at 1 month and 1 year after LKT. RESULT The 60- and 62-year-old men had renal graft transplantation performed in the right hemipelvis without complication. After LKT, urinary output and serum creatinine decrease were within acceptable ranges without evidence of an acute rejection episode for 12 and 7 months, respectively. Patient and graft survival rates were 100%. A protocol biopsy at 1 month after LKT showed additional treatment to be unnecessary. Serious viral infection was not seen, even in the 1 patient who temporarily experienced positive changes in cytomegalovirus antigenemia. CONCLUSIONS We obtained good clinical results among 2 high-titer ABO-i LKT using anti-CD20 and anti-CD25 antibodies without splenectomy, in conjunction with a calcineurin inhibitor plus mycophenolate mofetil or mizoribine.

Evaluation of rituximab dosage for ABO-incompatible living-donor kidney transplantation.

BACKGROUND The introduction of rituximab has led to a growing tendency to perform ABO-incompatible living-donor kidney transplantation (LDKT) without splenectomy. However, the optimal dosage of rituximab is undefined. METHOD Fifty-five LDKT recipients who had neither a history of hepatitis B infection nor positive crossmatch were enrolled between October 2005 and June 2014. Recipients were divided into three groups by year of transplantation: 2005 to 2008; 2009 to 2011; and 2012 to 2014. Percentages of CD20-positive B lymphocytes and blood-group antibody titers were monitored before renal transplantation. An initial rituximab dosage of 100 mg/body (for titers below 64) or 200 mg/body (for titers above 128) was administered 2 weeks before transplantation. If the percentage of peripheral B lymphocytes remained greater than 0.5%, additional rituximab (100 mg or 200 mg) was administered. Patient demographics, patient survival, graft survival, and complication rates were compared. RESULTS Nine patients received rituximab 100 mg/body (low-dose rituximab [LDR] group). Overall survival and graft survival rates did not differ significantly between the LDR group and other cases. The incidences of myelosuppression and viral infection were lower in the LDR group than the other cases. CONCLUSION A low dose of rituximab (100 mg/body) is adequate in ABO-incompatible LDKT, especially in cases with low blood-type antibody titer against ABO-antigens. Rituximab dosage reduction has been successful in our hospital without serious complications. Moreover, as over-dosage of rituximab may cause myelosuppression, it is reasonable to believe that LDR is a suitable option to safely perform ABO-incompatible LDKT without splenectomy.

Living-donor kidney transplantation with existing anti-donor specific antibodies at a Japanese single center.

Improving the short-term outcome of kidney transplantation, the rejection induced by anti-donor specific antibody (DSA) has been the large complication. We analyzed 324 living-donor kidney transplant recipients (procedures performed between April 2003 and August 2014) to investigate the outcome of kidney transplant recipients with DSA. We divided them into four groups (anti-blood type antibody alone, group A [n = 73]; anti-human lymphocyte antigen [HLA] antibody alone, group B [n = 11]; both antibodies, group C [n = 8]; and no DSA, group D [n = 232]) and investigated the incidence of rejection and those histologic findings. Each case with DSA underwent some desensitization therapy before transplantation. There was no significant difference in graft survival (all cases: 100% at 1 year, group A: 97.6%, B: 95.9%, C: 100%, and at 5 years, group D: 96.1%). There were some significant differences in incidence of acute antibody-mediated rejection (AAMR) and chronic active antibody-mediated rejection (CAAMR) among four groups (group A: 4.1% and 2.7%, B: 18.2% and 9.1%, C: 12.5% and 12.5%, D: 0% and 0.9%, respectively). Each AAMR case was improved by ordinary desensitization therapy, but half of the CAAMR cases, diagnosed early after transplantation, had no effect of any therapy to result in graft failure. Our results suggested that even the case with DSA could be transplanted safely by some desensitization therapy. However, we should be cautious regarding recipients with DSA for the long term even if there is no histologic change early after transplantation because graft loss may occur due to CAAMR.

Histopathologic impacts of everolimus introduction on kidney transplant recipients.

BACKGROUND Introduction of everolimus (RAD) has been established as a new immunosuppressive medication for kidney transplant (KT) recipients. Administration of RAD is capable of reducing the dosage of coadministrated calcineurin inhibitors (CNI). However, histological investigations have rarely been performed. METHODS To clarify histopathologic effects of RAD, a total of 9 adult KT recipients were enrolled (RAD group, n = 5; Mycophenolate mofetil (MMF) group, n = 4). Renal graft biopsies had been performed at 3 weeks and 1 year following KT. RESULTS There were no differences in 1-, 3-, and 5-year graft survival rates (RAD group: 100%, 100%, and 80%, respectively; MMF group: 100%, 100%, and 75%, respectively), and patient survival between the 2 groups (no deaths during the 5 years post-transplantation). Interestingly, although 2 patients in the RAD group had developed CNI nephrotoxicity clinically, renal biopsies had proven no CNI-related lesions 1 year later, which might be due to the reduction in CNI. On the other hand, 1 patient, in the MMF group, had been diagnosed histologically with new-onset CNI nephrotoxicity 1 year following KT. Importantly, the frequency and mean arteriolar hyalinosis (ah) scores, which reflect CNI nephrotoxicity, were significantly higher in the MMF group at 1-year biopsy (P < .05, P < .0001). Two patients in the RAD group improved their ah scores between 3 weeks and 1 year. CONCLUSIONS Pathological findings revealed that reversible CNI nephrotoxicity can be improved by RAD with reduced CNI maintenance therapy. It is reasonable to believe, therefore, that introduction of RAD is useful for patients who have been diagnosed with CNI nephrotoxicity.

Histological reversibility of diabetic nephropathy after kidney transplantation from diabetic donor to non-diabetic recipient

Given the recent increase in the prevalence of diabetes mellitus, it is not uncommon for kidney transplantation donors to have diabetes. We perform kidney transplantation in our hospital if the diabetic donors are receiving oral hypoglycaemic agents, but not insulin, and their haemoglobin A1C (HbA1C) is below 6.5%. There are few reports about histological changes to diabetic nephropathy after transplantation of kidney grafts from donors with diabetes mellitus to non‐diabetic recipients. Therefore, we studied the histological diabetic changes in grafts from diabetic donors at protocol biopsies (1 hour, 1 month, 1 year), and evaluated whether they improved under the recipients good glycaemic control.

Usefulness and Safety of High-dose Mizoribine on ABO-incompatible Living Related Kidney Transplantation Using Anti-cd20 and Anti-cd25 Antibodies Without Splenectomy: 3-year Results

BACKGROUND Mizoribine (MZR) has been developed as an immunosuppressive agent in Japan, but has a less potent immunosuppressive effect up to 3 mg/kg/d. We previously reported that high-dose MZR, at 6 mg/kg/d, would be effective and safe for ABO-incompatible(ABO-i) living donor kidney transplantation (LDKT) patients when combined with cyclosporine (CsA) or tacrolimus(FK), anti-CD20 and anti-CD25 monoclonal antibodies, and corticosteroid without splenectomy in a 1-year study. Therefore, we observed these patients for 3 years. METHODS From 2007 to 2010, we encountered 24 cases of ABO-i LDKT using anti-CD20 and anti-CD25 monoclonal antibodies without splenectomy. The pretransplantation immunosuppressive regimen consisted of two doses of anti-CD20 antibody, mycophenolate mofetil (MMF, 25 mg/kg/d), prednisolone, calcineurin inhibitor (CNI; CsA 7 mg/kg or (FK 0.2 mg/kg) and two doses of anti-CD25 antibody. Antibody removal by plasmapheresis was performed before LDKT up to several times according to the antibody titer. The post-transplantation regimen consisted of high-dose MZR (6 mg/kg/d) instead of MMF (MZR group, N = 12) . RESULTS The 3-year graft survival rates for the MZR and MMF groups were 91.7% and 100%, respectively. Serum creatinine levels for the MZR and MMF groups were 1.44 mg/dL and 1.31 mg/dL at 1 year, 1.55 mg/dL and 1.41 mg/dL at 2 years, and 1.51 mg/dL and 1.48 mg/dL at 3 years, respectively (not significant [NS]). The MZR group did not show a higher rate of elevated serum uric acid values. The percentage of patients who were administered anti-uric medication was 42.5% (5/12) in the MZR group and 50% (6/12) in the MMF group (P = NS) at the third year. Severe infection, such as cytomegalovirus, herpes zoster, was not observed at the second and third years in both groups. CONCLUSION A high-dose MZR regimen including CNI (CsA or FK), steroid, and anti-CD20 and anti-CD25 antibodies without splenectomy was effective and safe in ABO-i renal transplantation.

Excellent Results of High-Dose Mizoribine Combined With Cyclosporine, Basiliximab, and Corticosteroids in Renal Transplant Recipients—4-Year Results

BACKGROUND Mizoribine (MZR) at 3 mg/kg/d shows less potent immunosuppressive effects, but high-dose MZR (6 mg/kg/d) was effective and safe in a 2-year study in conjunction with a regimen of cyclosporine (CsA), basiliximab, and corticosteroids. METHODS We compared 40 living-related kidney recipients administered MZR (6 mg/kg/d), CsA (7 mg/kg/d), prednisolone (maintenance dose 10 mg/d), and basiliximab (20 mg/body) with control group (n = 38) treated with CsA, mycophenolate mofetil (MMF; 25 mg/kg/d), basiliximab, and corticosteroids. RESULTS The 4-year graft survival rates for the MZR vs MMF groups were 92.5% vs 94.7%, respectively, with serum creatinine levels of 1.66 ± 1.0 mg/dL vs 1.41 ± 0.42 mg/dL at 3 years, and 1.72 ± 1.16 mg/dL vs 1.56 ± 1.26 mg/dL at 4 years. There was no significant difference in serum creatinine levels between the 2 groups. The MZR group demonstrated a significantly higher rate of elevated serum uric acid values (29.7%). The numbers of patients treated with allopurinol at 4 years were 11/37 (29.7%) for MZR vs 2/36 (5.6%) for the MMF subjects (P < .05). Mean serum uric acid levels of the MZR vs MMF group at 4 years were 7.1 ± 1.9 mg/dL vs 7.0 ± 1.6 mg/dL, respectively (NS). There was no significant difference between the 2 groups regarding bone marrow suppression or liver dysfunction. Severe cytomegalovirus infection was not observed at 3 and 4 years in either group. There were no severe gastrointestinal symptoms among the MZR or the MMF group at 3 or 4 years. CONCLUSIONS The combination of high-dose MZR with CsA, basiliximab, and corticosteroids displayed excellent results over a 4-year follow-up.

Results of Kidney Transplantation for Diabetic Nephropathy: A Single-Center Experience

In Japan, diabetic nephropathy accounted for 16,225 (43.7%) of the 38,473 patients who began hemodialysis in 2010 and the number increases year by year. In 1991, we started a kidney transplantation program for patients with diabetic nephropathy in our institution, and the ratio of patients who underwent kidney transplantation for diabetic nephropathy traces the course of increase. Among the 516 patients who underwent primary kidney transplantation in our institution from January 1991 to February 2013, we divided them into 2 groups. One group was the diabetes mellitus (DM) group, which included patients with primary disease of diabetic nephropathy, and the other group was the non-DM group. The DM group included 50 patients, and in our institution the ratio traces the course to increase. There was no significant difference for the 1-year and 5-year patient survival rates and graft survival rates between the DM group and the non-DM group. Moreover, the rate of acute rejection in the 2 groups was not significantly different. Furthermore, when we investigated the causes of death in the 2 groups, there was no significant difference with the mortality of cases due to heart vascular disease in the DM group and the non-DM group. Also, no case in which the graft lost function due to recurrence of diabetic nephropathy was observed. Although the early outcome of kidney transplantation for diabetic nephropathy in our institution did not have inferiority in comparison with kidney transplantation for the other primary disease, we think that careful diabetic control after kidney transplantation is required for long-term outcome.