Kei Kurihara

Effect of Milrinone on Ischemia-Reperfusion Injury in the Rat Kidney

BACKGROUND Milrinone (MIL), a phosphodiesterase (PDE) 3 inhibitor, exhibits cardiotonic and angioectatic effects. Various PDE inhibitors have been shown to suppress inflammatory cytokines. In this study, we evaluated the angioectatic and anti-inflammatory cytokine effects of MIL on renal function after warm ischemia in a rat ischemia-reperfusion (I-R) injury model. MATERIALS AND METHODS MIL or control solution was perfused from the left renal artery to the right kidney, and the left kidney was excised. The right renal artery, vein, and ureter were clamped and then released after 50 minutes to produce warm ischemia. We evaluated control (n = 7), MIL (n = 7), and sham operation (n = 7) groups for serum creatinine, blood urea nitrogen (BUN), blood flow, expression of tumor necrosis factor (TNF)-α mRNA, apoptosis index, and histological evidence of acute tubular necrosis. RESULTS Serum creatinine and BUN concentrations peaked at 24 hours after reperfusion. MIL treatment significantly reduced serum creatinine (control group 1.27 ± 0.45 mg/dL vs MIL group 0.77 ± 0.19 mg/dL, P < .05; sham 0.35 ± 0.2 mg/dL) and BUN (control 67.6 ± 13.6 mg/dL vs MIL 51.0 ± 8.8 mg/dL, P < .05; sham 23.0 ± 4.2 mg/dL) levels at 24 hours. Thereafter, serum creatinine and BUN concentrations in the MIL group remained significantly lower compared with the control group for 120 hours (P < .05). MIL group exhibited significantly higher tissue blood flow, less acute tubular necrosis, lower expression of TNF-α mRNA in renal tissue, and lower apoptotic index (P < .05). CONCLUSIONS MIL maintained renal tissue blood flow by its vasodilatory effect, suppressed expression of TNF-α mRNA by increasing intracellular cyclic adenosine monophosphate, and ultimately decreased tubular cell apoptosis, thus protecting renal function after warm I-R injury.

One-year follow-up of treatment with once-daily tacrolimus in de novo renal transplant

OBJECTIVES The once-daily prolonged-release formulation of tacrolimus (tacrolimus QD) is expected to demonstrate equivalent efficacy and safety to the twice-daily formulation (tacrolimus BID). We reviewed the 1-year outcomes of tacrolimus QD in de novo renal transplant. MATERIALS AND METHODS We reviewed 50 de novo renal transplant patients assigned in a nonrandomized fashion to either tacrolimus QD (n=23, historic control group) or tacrolimus BID (n=27). Other immunosuppressive drugs used in both groups included mycophenolate mofetil, basiliximab, and steroids. We evaluated trough levels, required dosages, renal function, rejection rates, and episodes of infection within 1 year after transplant. RESULTS Trough levels of both drugs varied during the perioperative periods, but subsequently stabilized in both groups. There was a tendency toward a slow elevation and a higher dosage requirement in the tacrolimus QD group, compared with the tacrolimus BID group in the early stages, though the required dosages decreased steadily. The rejection rate in the tacrolimus QD group was low, and only 1 patient experienced subclinical rejection. No severe infectious adverse events were observed. CONCLUSIONS Patients taking tacrolimus QD tended to have lower trough levels and require higher dosages than those taking tacrolimus BID during the early posttransplant period, though the differences decreased with increasing time after transplant. Tacrolimus QD can be administered with excellent efficacy and safety in de novo renal transplant recipients.

Availability of Pancreatic Allograft Biopsies Via a Laparotomy

OBJECTIVE The aim of this study was to evaluate the availability of a pancreatic allograft biopsy via a laparotpmy. PATIENTS AND METHODS From September 2004 to November 2007, 17 pancreas transplantations were performed: 15 simultaneous pancreas and kidney transplantations (SPK), 1 pancreas transplant alone (PTA), and one pancreas after kidney transplantation (PAK). Thirteen pancreatic allograft biopsies were obtained via an open laparotomy. This study evaluated the complications associated with this procedure, the rate of obtaining an adequate sample, and the relationship between biopsy-proven rejections and laboratory markers. In SPK cases we evaluated the synchronization between pancreas and kidney rejection. The pancreatic samples were diagnosed according to the Drachenberg classification. RESULTS No complications resulted from the procedure. The rate of obtaining adequate samples was 84.6%. Pancreas rejection correlated with elevation of the laboratory markers in 71.4%. Simultaneous pancreas and kidney rejection occurred in 62.5%, only kidney in 25%, and only pancreas in 12.5%. CONCLUSION A pancreas graft biopsy was absolutely imperative to improve the outcome in PTA, and even in SPK cases. A pancreatic allograft biopsy via a laparotomy was a safe, necessary and easy procedure to obtain an accurate diagnosis of rejection among pancreas transplantation patients.

Temporal serum creatinine increase and exacerbation of tubulointerstitial inflammation during the first two months in resolving polyomavirus BK nephropathy

Polyomavirus BK nephropathy (BKVN) is an important complication in kidney transplantation. After immunosuppressive agents are reduced, some patients experience a temporal increase in serum creatinine (sCr) before viral clearance. The histological characteristics of re‐biopsies were therefore investigated to evaluate the time course of remission.

Effect of Cell Permeable Peptide of c-Jun NH2-Terminal Kinase Inhibitor on the Attenuation of Renal Ischemia-Reperfusion Injury in Pigs

The outcomes of organ transplantation have improved due to better immunosuppressive drugs, surgical techniques, and management of complications. However, ischemia-reperfusion injury remains a challenge affecting graft survival. In this study, we employed injection of a protein transduction domain (PTD) to inhibit the c-Jun NH2-terminal kinase (JNK) pathway thereby attenuating ischemia-reperfusion injury in a porcine model. The PTD-JNK inhibitor (JNKI) was administered into the renal artery, allowing it to be taken into various elements including vascular endothelial cells by endocytosis via the PTD. Serum creatinine and blood urea nitrogen concentrations were lower among PTD-JNKI than controls. In addition, renal tissue blood flow was maintained in the PTD-JNKI group, resulting in less tissue injury and fewer apoptotic cells. These results suggested that the PTD technique improved renal transplantation outcomes.

Histological Analysis in Abo-compatible and Abo-incompatible Kidney Transplantation by Performance of 3- and 12-month Protocol Biopsies.

Background ABO-incompatible (ABO-I) kidney transplantation (KTx) is an established procedure to expand living donor sources. Although graft and patient survival rates are comparable between ABO-compatible (ABO-C) and ABO-I KTx, several studies have suggested that ABO-I KTx is associated with infection. Additionally, the histological findings and incidence of antibody-mediated rejection under desensitization with rituximab and plasmapheresis remain unclear. Methods We reviewed 327 patients who underwent living-donor KTx without preformed donor-specific antibodies (ABO-C, n = 226; ABO-I, n = 101). Patients who underwent ABO-I KTx received 200 mg/body of rituximab and plasmapheresis, and protocol biopsy (PB) was planned at 3 and 12 months. We compared the PB findings, cumulative incidence of acute rejection in both PBs and indication biopsies, infection, and patient and graft survivals. Results The 3- and 12-month PBs were performed in 85.0% and 79.2% of the patients, respectively. Subclinical acute rejection occurred in 6.9% and 9.9% of patients in the ABO-C and ABO-I groups at 3 months (P = 0.4) and in 12.4% and 10.1% at 12 months, respectively (P = 0.5). The cumulative incidence of acute rejection determined by both PBs and indication biopsies was 20.5% and 19.6%, respectively (P = 0.8). The degrees of microvascular inflammation and interstitial fibrosis/tubular atrophy were comparable. Polyomavirus BK nephropathy was found in 2.7% and 3.0% of patients in the ABO-C and ABO-I groups, respectively (P = 1.0). The incidence of other infections and the graft/patient survival rates were not different. Conclusions Analyses using 3- and 12-month PBs suggested comparable allograft pathology between ABO-C and ABO-I KTx under desensitization with low-dose rituximab and plasmapheresis.

Living Donor Renal Transplantation Using Grafts With Multiple Arteries Procured by Laparoscopic Nephrectomy

OBJECTIVE Kidney grafts with multiple renal arteries (MRAs) are not uncommon, but they do make transplantation more difficult. Laparoscopic graft nephrectomy has become the standard; however, the safety and reliability must be maintained for both a donor and a recipient even in case of MRAs. This study evaluated the short-term outcomes of living donor renal transplant using grafts with MRAs procured by laparoscopic nephrectomy. PATIENTS AND METHODS This study reviewed all living donor kidney transplantations performed from January 2008 to June 2009, which were divided into 3 groups according to the number of renal graft arteries. The serum creatinine level, warm ischemic time (WIT), rewarming time, total ischemic time (TIT), operative time, acute rejection episodes, and complications in each group were evaluated. RESULTS The serum creatinine level showed no difference among the groups. Longer TIT was observed in the MRAs group, but WIT and rewarming time did not differ. The acute rejection rate was not different. There were no vessel complications in any donors and recipients. CONCLUSION Harvesting kidney grafts with MRAs by laparoscopic nephrectomy requires a longer TIT; however, transplantation can be performed safely and reliably for both donors and recipients.

Living Donor Kidney Transplantation Preceding Pancreas Transplantation Reduces Mortality in Type 1 Diabetics With End-stage Renal Disease

BACKGROUND Simultaneous pancreas-kidney transplantation (SPK) is a definitive treatment for type 1 diabetics with end-stage renal disease (ESRD). Because of the shortage of deceased donors in Japan, the mortality rate during the waiting period is high. We evaluated mortality risk in patients with type 1 diabetes waiting for SPK, and the benefit of living-donor kidney transplantation (LDK) preceding pancreas transplantation, which may reduce mortality in patients awaiting SPK. METHODS This retrospective study included 71 patients with type 1 diabetes. Twenty-six patients underwent SPK, 15 underwent LDK, and 30 were waiting for SPK. Their cumulative patient and graft survival rates were retrospectively evaluated. Risk factors contributing to mortality in patients with type 1 diabetes awaiting SPK were evaluated with the use of a Cox proportional hazards model. RESULTS The 5-year cumulative patient survival rates in the SPK and LDK groups were 100% and 93.3%, respectively (P = .19), and 5-year kidney graft survival rates were 95.7% and 100% (P = .46), respectively. The cumulative survival rate in patients awaiting SPK was 77.7% at 5 years after registration. Duration of dialysis was the only factor significantly associated with patient and graft survivals according to both univariate and multivariate analyses. CONCLUSIONS Patient and graft survival rates were similar in the SPK and LDK groups, but the survival rate of patients awaiting SPK decreased over time. Duration of dialysis was an independent risk factor for patient and graft survival. LDK preceding pancreas transplantation may be an effective therapeutic option for patients with type 1 diabetes and ESRD.

Outcome of Renal Transplantation in Patients With Type 2 Diabetic Nephropathy: A Single-Center Experience

BACKGROUND Renal transplantation has been established as a treatment for end-stage renal disease (ESRD) due to diabetic nephropathy. However, few studies have focused on the outcome after renal transplantation in patients with ESRD and type 2 diabetic nephropathy. To investigate the effect of renal transplantation on ESRD with type 2 diabetic nephropathy, we retrospectively analyzed patients who received renal transplantation at our facility. This study aimed to compare the outcome of renal transplantation for type 2 diabetic nephropathy with that for nondiabetic nephropathy. METHODS We studied 290 adult patients, including 65 with type 2 diabetic nephropathy (DM group) and 225 with nondiabetic nephropathy (NDM group), who underwent living-donor renal transplantation at our facility from February 2008 to March 2013. We compared the 2 groups retrospectively. RESULTS In the DM and NDM groups, the 5-year patient survival rates were 96.6% and 98.7%, and the 5-year graft survival rates were 96.8% and 98.0%, respectively, with no significant differences between the groups. There were no significant differences in the rates of surgical complications, rejection, and infection. The cumulative incidence of postoperative cardiovascular events was higher in the DM group than in the NDM group (8.5% vs 0.49% at 5 years; P = .002). CONCLUSIONS Patient and graft survival rates after renal transplantation for type 2 diabetic nephropathy are not inferior to those for recipients without diabetic nephropathy. Considering the poor prognosis of patients with diabetic nephropathy on dialysis, renal transplantation can provide significant benefits for these patients.

A Study of Effectiveness of Preceding Solo-Kidney Transplantation for Type1 Diabetes with End Stage Renal Failure

Background Patients with type 1 diabetes associated with end stage renal failure are indicated for simultaneous pancreas and kidney transplantation (SPK), but if the living donor is available, can transplant surgeons recommend that preceding solo-kidney transplantation prior to pancreatic transplantation be carried out? Methods To study of effectiveness of preceding solo-kidney transplantation for type1 Diabetes with end stage renal failure, comparative retrospective analysis was performed between SPK (n=232) and pancreas transplantation after kidney (PAK) (n=39) which have been performed until December 2016. Results 1. Is the waiting period prolonged for pancreas transplantation if kidney transplantation is preceded? We compared the waiting periods of 232 cases of SPK and 39 cases of PAK that were carried out in Japan until December 2016. The median waiting period was SPK: 1127 (11-4974) days and PAK: 710 (58-4453) days, showing no statistically significant difference (p=0.078) but having a shorter tendency in PAK. 2. After PAK, does renal function deteriorate? Among 35 cases of PAK who had undergone surgery one year prior, s-Cre values before surgery and one year after surgery were compared. It was found that s-Cre one year after surgery had statistically significantly increased (p=0.022). However, the median sCre had slightly increased from 1.18 mg/dl before surgery to 1.21 mg/dl one year after surgery, which is not considered clinically problematic. 3. Is pancreatic graft survival the same with SPK? 1, 3 and 5-year pancreatic graft survival after SPK was 87.5%, 86.4%, 82.8%, respectively, and 87.1%, 65.0%, 49.1% after PAK, indicating no difference in 1-year survival. Upon examining the causes of pancreatic graft loss, graft loss occurred due to rejection among 8/37 cases (21.6%) after SPK; whereas after PAK it occurred for the same reason among 10/16 cases (62.5%), indicating significantly higher occurrence of pancreatic graft loss due to rejection (p=0.01). However, in PAK using rATG for induction, rejection occurred as a complication among 2/15 cases (12.3%), indicating a lower tendency compared to that occurring among cases in which rATG was not used (10/24 cases, 41.7%). Moreover, while 5-year pancreatic graft survival was 37.6% after PAK not using rATG, it was revealed that survival of 78.8% could be maintained in cases of rATG induction. 4. Can the prognosis be improved by a preceding kidney transplantation? The life prognosis of patients waiting for SPK and PAK was compared.1, 3, and 5-year survival of patients waiting for SPK was 98.4%, 92.1%, and 88.0%, respectively, while that of patients waiting for PAK was 100%, 96.6%, and 96.6%, with the life prognosis of patients waiting for PAK significantly better than those waiting for SPK (p=0.029). Conclusion According to considering patient survival, preceding solo-kidney transplantation for type1 Diabetes with end stage renal failure should be performed if donor is available.