Analysis of risk factors for donation after circulatory death kidney transplantation in Japan.

BACKGROUND: In Japan, donations after circulatory death kidney transplantation are widely performed due to legislation delays. The number of donations after brain death kidney transplantations is increasing, but the target remains unmet. We reviewed the outcomes of donation after circulatory death in Japan. METHODS: We analyzed 2923 deceased kidney transplantations (2239: donation after circulatory death (DCD), 684: donation after brain death (DBD)) performed in Japan from 2000 to 2019. The outcomes of the DCD and DBD groups were compared. We examined the risk factors for graft loss in the DCD group. RESULTS: The 5-year patient survival and death-censored graft survival rates of the DCD group, obtained by propensity score matching, were 93.6% and 95.2%, respectively, which were equivalent to 94.2% and 93.8%, respectively, obtained in the DBD group. Older donors (≥ 50 years) and prolonged cold ischemia time (≥ 12 h) were risk factors for graft loss; in the presence of these, graft survival was lower in the DCD group. CONCLUSIONS: Older donors and prolonged cold ischemia time reduced graft survival in the DCD group. Proper evaluation of donors and careful preparation for transplant surgery are, therefore, essential to ensure good transplant outcomes.

National survey on deceased donor organ transplantation during the COVID-19 pandemic in Japan.

PURPOSE: We investigated the status of deceased organ donation and transplantation through a questionnaire distributed to transplant centers in Japan during the COVID-19 pandemic. METHODS: The questionnaire was distributed electronically to 206 transplant centers for heart (n = 11), lung (n = 10), liver (n = 25), kidney (n = 130), pancreas (n = 18), and small intestine (n = 12) transplantation. Organ donations and organ transplantation data were extracted from the Japan Organ Transplant Network website. RESULTS: We received questionnaire responses from 177 centers (response rate, 86%). In 2020, the number of brain-dead donors (BDDs) decreased to 68 (69% of the year-on-year average) and the number of donors after cardiac death (DCDs) decreased to 9 (32% of the year-on-year average). Eighty-five (48%) transplant centers (heart, n = 0; lung, n = 0; liver, n = 4; kidney, n = 78; pancreas, n = 22; and small intestine, n = 0) suspended transplant surgeries in response to the COVID-19 pandemic. Consequently, the number of organ transplantations from deceased donors was significantly lower in 2020 than in 2019. CONCLUSION: Although the COVID-19 pandemic has had less impact in Japan than in other countries, it has affected transplantation activity significantly, suspending transplantation surgeries in 48% of the transplantation centers, including 78% of the kidney transplantation centers, and reducing the number of organ donations to 61% of the year-on-year average.

Outcomes of pancreas transplantation in older versus younger recipients: a comparative analysis.

PURPOSE: The feasibility of pancreas transplantation (PT) in older recipients remains a matter of debate. We examined the influence of recipient age on PT outcomes and identified the prognostic factors for older recipients. METHODS: We compared the outcomes of PT in recipients aged < 50 years (younger group; n = 285) with those in recipients aged ≥ 50 years (older group; n = 94). Prognostic factors in the older group were analyzed by a logistic regression model and the influence of recipient age on survival outcomes were analyzed using propensity score matching. RESULTS: The patient survival rate was significantly worse in the older group (P < 0.001). Patient death from infection or/and multiple organ failure or cardiac/cerebrovascular events was also more frequent in the older group than in the younger group (P = 0.012 and P = 0.045, respectively). A longer duration of diabetes was an independent risk factor of 1-year mortality in the older group. In a propensity score-matched comparison, the older recipients (n = 77) had significantly poorer survival than the younger recipients (n = 77) (P = 0.026). CONCLUSIONS: PT should be considered with appropriate caution, especially for older recipients with a long duration of diabetes.

Are the outcomes of Japanese pancreas transplantation utilizing extended-criteria donors acceptable? A propensity score matching analysis for donors <50 or ≥50 years old.

In Japan, about 30% of pancreatic transplant donors are ≥50 years old, making them "extended-criteria donors (ECDs)." We analyzed 361 cases of transplantation involving donors from the Japanese pancreas transplantation registry to evaluate the acceptability of ECDs. The patient survival rates at 1, 5, and 10 years after transplantation were 96.6%, 94.9%, and 88.3%, respectively. The survival rates of pancreas and kidney grafts at 1, 5, and 10 years were 85.3%, 74.8%, and 70.6%, and 94.2%, 90.9%, and 80.9%, respectively. Multivariate analysis revealed that no particular donor factors significantly influenced the pancreatic graft survival. Patients were divided into 2 groups: donors ≥50 years old (older group) and those <50 years old (younger group). After propensity score matching, the overall pancreatic graft survival at 1, 5, and 10 years after transplantation in the older group was 82.8%, 71.8%, and 69.5%, respectively, which was almost the same as in the younger group (84.9%, 70.2%, and 67.4%, respectively). No donor factors markedly influenced the pancreatic graft survival, and the outcomes of pancreas transplantation from ECDs ≥50 years old were comparable to those from younger donors.

Age and Pre-operative HbA1c levels affect renal function compensation in living kidney donors.

OBJECTIVES: About 90% of Japanese kidney transplantations are conducted from living donors, and their safety and the maintenance of their renal function are critical. This study aims to identify factors that affect the compensation of renal function in living kidney donors after donor nephrectomy. METHOD: In a retrospective cohort study, we reviewed data from 120 patients who underwent nephrectomy as living kidney transplant donors in our department from 2012 to 2021. Univariable and multivariable linear regression analyses were performed for donor factors affecting renal function after donor nephrectomy. RESULT: The multivariable linear regression model revealed that the donor's age (p = 0.025), preoperative estimated Glomerular Filtration Rate (eGFR) (p < 0.001), and hemoglobin A1c (HbA1c) (p = 0.043) were independent risk factors for eGFR at six months after nephrectomy. The eGFR deterioration was more strongly associated with age in females than in males, whereas higher HbA1c values were more strongly associated with eGFR deterioration in males. Higher donor age and higher HbA1c each enhance the deterioration of eGFR six months after living donor nephrectomy. The data suggest that old age in especially female donors and preoperative higher HbA1c in male donors have a harmful impact on their renal function compensation.

An Examination of Packing Methods for Grafts to Prevent Freezing Injury during Transportation for Liver Transplantation.

BACKGROUND: University of Wisconsin solution (UW) may freeze at temperatures below -0.7 °C, damaging the graft. The present study assessed the effectiveness of the liver graft package protocol, which recommends filling a package with sufficient liquid to prevent grafts from sustaining freezing injury. METHODS: We filled ice cubes at two temperatures (-80 and -20 °C) around packages and performed a comparative study with four groups based on the temperature and filling of the second layer with lactated Ringer's solution (LR) (A: -80 °C, LR-; B: -80 °C, LR+; C: -20 °C, LR-; D: -20 °C, LR+). The bovine liver was used as a graft and preserved for 6 h in the first isolation bag filled with UW. RESULTS: While temperatures dropped below -0.7 °C at some points for 6 h in groups A, B, C, they never dropped to -0.7 °C in group D. The macroscopic findings in groups A, B, C showed freezing of the UW and grafts, but no such results in group D. A pathological study including electron microscopy showed freezing injury in groups A, B, and C but no significant changes in group D. CONCLUSIONS: The graft package protocol prevents freezing of the UW and liver grafts.

Total Cell-Free DNA as a Noninvasive Biomarker of a Delayed Graft Function After Kidney Transplantation From Donors After Cardiac Death.

BACKGROUND: Because of the organ shortage, donation after cardiac death (DCD) kidney transplantation (KTx) is an alternative way of achieving KTx using brain-dead donors (BDs). Although the prognosis of DCD-KTx is improving, the graft suffers from delayed graft function (DGF), the management of which is essential. With progress in understanding the characteristics of cell-free DNA (CF-DNA), we consider plasma total CF-DNA (tCF-DNA) to be a useful biomarker for predicting DGF in DCD-KTx. STUDY DESIGN AND METHOD: Consecutive patients from living donors (LDs; n = 9), BDs (n = 8), or DCD donors (n = 13) were enrolled. Plasma samples were collected after KTx and on postoperative days 3 and 5. CF-DNA was isolated, and tCF-DNA was quantified using the TapeStation 2200 software program. RESULTS: The tCF-DNA levels after BD-KTx and DCD-KTx were higher than those after LD-KTx (LD, 78 ± 27 (ng/mL); BD, 99 ± 20; DCD, 150 ± 23); the difference between DCD-KTx and LD-KTx was statistically significant (P < .05). The tCF-DNA levels declined at postoperative day 5 (LD, 45 ± 10; BD, 51 ± 11; DCD, 66 ± 13). tCF-DNA levels were significantly increased in patients with DGF after KTx (DGF, 139 ± 22; immediate function, 91 ± 18; P < .05). The tCF-DNA level was correlated with the duration of DGF (r = 0.5825, P < .05). CONCLUSION: Although the mechanism underlying DNA release from transplanted grafts into the recipient circulation remains unclear, cell death by apoptosis or necrosis and the active secretion of the immune system may play important roles in DGF. These data suggest that monitoring tCF-DNA may help predict graft recovery after DCD-KTx.

Impact of B Cell Depletion on COVID-19 in Kidney Transplant Recipients.

Kidney transplant recipients are patients at high risk for coronavirus disease 2019 (COVID-19) due to being on immunosuppressive therapy. B cell depletion therapy, including rituximab, is an important strategy for ABO-incompatible transplants. However, knowledge about the effect of B cell depletion therapy on COVID-19 is lacking. Thirty kidney transplant recipients who developed COVID-19 were included in this study. To examine the impact of B cell depletion therapy, we retrospectively investigated the relationship between the background of the patients and the clinical outcome. Of the 30 patients, 13 received B cell depletion therapy. The median time between transplant and onset of COVID-19 was 6.1 years after transplantation; however, nine cases remained markedly depleted of CD19(+) cells (<4.0%). The patients were assigned to the normal (n = 21) and depletion groups (n = 9). Progression rates in the depletion and normal groups were 55.6% and 9.5%, respectively (p = 0.014). Furthermore, the survival rate was significantly lower in the depletion group (100% in the normal group vs. 66.7% in the depletion group; p = 0.021). B cell depletion therapy may have long-term effects and increase the risk of COVID-19 in kidney transplant recipients.

Outcomes of Pancreas Transplantation for Lower-Ranked Candidates.

BACKGROUND: To perform more pancreas transplantation (PTx), our center sometimes performs pancreas transplantation for candidates ranked sixth place or lower. In this study, we analyzed the outcomes of PTx performed in our center to compare the outcomes of higher- and lower-ranked candidates. METHODS: Seventy-two cases in which PTx was performed at our center were divided into 2 groups according to the candidate's rank. Cases in which PTx was performed for candidates up to fifth place were classified into the higher rank candidate group (HRC group; n = 48), whereas PTx for candidates who were ranked sixth place or lower were classified into the lower rank candidate group (LRC group; n = 24). The outcomes of PTx were retrospectively compared. RESULTS: Although the LRC group included a greater number of older donors (age ≥60 years), a greater number of donors with deteriorated renal function, and a greater number of HLA mismatches, the 1- and 5-year patient survival rates in the HRC group were 91.6% and 91.6%, respectively, compared with 95.8% and 87.0%, respectively, in the LRC group (P = .755). In terms of both pancreas and kidney graft survival, there were no significant differences between the 2 groups. Additionally, there were no significant differences between the 2 groups regarding the glucagon stimulation test and 75 g OGTT results, insulin independence rate, HbA1c, or serum creatinine level after transplantation. CONCLUSIONS: In Japan, where there is a severe donor shortage, the performance of transplantation for lower-ranked candidates would increase the number of opportunities for patients to receive PTx.

Pancreas transplantation improves the quality of life of Japanese type 1 diabetes patients with diabetic kidney disease.

Objectives: Type 1 diabetes mellitus (T1DM) patients with diabetic kidney disease-induced kidney failure have a significantly impaired quality of life (QOL), resulting in a high level of physical, mental, and social anxiety. In this study, we evaluated the QOL of T1DM patients on the list for pancreas transplantation (PTx) at their registration, and determined whether PTx improved their QOL. Methods: There were 58 patients (men/women, 22/36; mean age, 42.8±8.0 years) with T1DM and who were registered on the waiting list for PTx. Quantitative QOL assessment was performed using the Medical Health Survey Short Form (SF-36) version 2. Changes in the QOL before and after PTx were also examined in 24 of these patients. Results: The mean value of each endpoint and the summary score of the SF-36 physical (PCS), mental (MCS), and role (RCS) components were all below the national normal level at PTx registration. No significant difference in QOL scores was observed in the intergroup comparison of 35 patients on dialysis, 13 patients without dialysis, and ten patients after kidney transplantation. The 24 patients who underwent PTx showed improvement in PCS, MCS, and most SF-36 scores. Conclusion: T1DM patients waiting for PTx had a decreased QOL, regardless of dialysis, and PTx improved their QOL.

First Multicenter Clinical Trial on Machine Perfusion Preservation for Marginal Donor Kidney Transplantation in Japan.

BACKGROUND: Machine perfusion has not been widely used because of its low demand in Japan; however, we believe its advantages may increase the number of organ transplants. METHODS: Here, we report the first clinical trial of machine perfusion for kidney transplantation in Japan. We used the CMP-X08 perfusion device (Chuo-Seiko Co, Ltd, Asahikawa, Hokkaido, Japan) to preserve the donated organs. The flow rate, perfusion pressure, renal resistance, and temperature were monitored during continuous hypothermic perfusion. RESULTS: From August 2020 to the present, 13 cases of perfusion-preserved kidney transplantation have been performed. Of these, ten and 3 cases were performed using organs donated after brain death (DBD) and cardiac death (DCD), respectively. The average age of the recipients was 55.9 ± 7.3 (45-66) years. The average dialysis period was 14.8 ± 8.4 (0-26) years. The donor's final creatinine level before organ retrieval was 1.58 ± 1.0 (0.46-3.07) mg/dL. The warm ischemic times of the 3 DCD donors were 3, 12, and 18 minutes. The average total ischemic time was 12.0 ± 3.7 (7.17-19.88) hours. The average MP time was 140 (60-240) minutes. A total of 7 cases had delayed graft function. The best creatinine level during hospitalization was 1.17 ± 0.43 (0.71-1.85) mg/dL. There were no primary non-functional cases, and perfusion preservation was safely performed in all cases. CONCLUSIONS: Therefore, we present this report as the first clinical trial on machine perfusion for kidney transplantation from marginal donors with DBD and DCD in Japan.

The History of Clinical Islet Transplantation in Japan.

Islet transplantation shows the promise of being capable of relieving glucose instability and improving QOL of patients with type 1 diabetes that cannot be controlled due to severe hypoglycemia unawareness. In Japan, following the first human islet isolation from a donor after cardiac death in 2003 and the first clinical islet transplantation in 2004, islet transplantation was performed for the improvement of type 1 diabetes as a single-center trial in several centers. Although it was discontinued due to the possibility of contamination of collagenase by bovine brain component in 2007, the phase II clinical trial of islet transplantation started using ATG induction and a TNF-α inhibition protocol in 2012. The primary endpoints of this trial were the proportion of patients with HbA1c < 7.4% and freedom from severe hypoglycemic events at one year after the first islet cell infusion. In an interim analysis, this endpoint was achieved in 75% of cases. In April 2020, clinical islet transplantation was finally covered by health insurance in Japan, thanks to these outcomes. We herein introduce more than 20 years of history of clinical islet transplantation in Japan.

Evaluation of the Efficacy and Effects of Common Hepatic Artery Reconstruction in Pancreas Transplantation: A Randomized Controlled Trial.

Maintenance of postoperative graft flow is important in pancreas transplantation. In Japan, reconstruction of the common hepatic artery is performed primarily to increase perfusion in the pancreatic head. We investigated the effects of common hepatic artery reconstruction on patient and graft survival and endocrine functions. Twenty-nine cases of pancreas transplantation were registered in the clinical trial. Of the 29 cases, four were excluded because of the risk of ischemia without reconstruction or complicated reconstruction due to a narrow artery. A total of 25 cases were randomized into two groups: 13 in the non-reconstructed group and 12 in the reconstructed group. The 1-year patient survival and graft survival rates of the non-reconstructed and reconstructed groups were 92.3% and 83.3%, and 91.7% and 82.5%, respectively. The incidence of complications in the two groups was comparable, with 38.5% (5/13 cases) in the non-reconstructed group and 33.3% (4/12 cases) in the reconstructed group. The results of the glucagon stimulation test and oral glucose tolerance test at 1 month and 1 year post-transplantation were comparable. Common hepatic artery reconstruction is not essential unless there is risk of ischemia. This study was registered at the University Hospital Medical Information Network Clinical Trials Registry under UMIN000027213.

Feasibility of the automated column agglutination technique for titration of anti-A/B antibodies in ABO-incompatible living kidney transplantation.

INTRODUCTION: Quantitative measurement of anti-A/-B antibody titers is important during ABO-incompatible living kidney transplantation (ABOi-LKT). METHODS: We conducted a multi-institutional study to measure the antibody titers using the automated column agglutination technique (auto-CAT) and tube test (TT) method in ABOi-LKT recipients. Statistical analysis was performed to evaluate the two methods. RESULTS: We examined 111 samples from 35 ABOi-LKT recipients at four institutions. The correlation coefficient of the two methods was >0.9; the concordance rate and clinically acceptable concordance rate for the IgG titers were 60.4% and 88.3%, respectively. Perioperative status did not influence the statistical significance. Parallel changes were observed in the IgG antibody titers measured using the auto-CAT or TT technique by desensitizing therapy in time-course monitoring. CONCLUSION: Auto-CAT is comparable with the TT technique and is feasible for IgG anti-A/B antibody titration in ABOi-LKT recipients.

An Examination of Donor Factors That Impact the Results of the Glucagon Stimulation Test as an Assessment of the Pancreatic Graft Endocrine Function.

OBJECTIVES: Delta C-peptide derived by the glucagon stimulation test is a reliable value for the evaluation of the pancreatic endocrine function after pancreas transplantation. We examined the associations between delta C-peptide as pancreatic graft endocrine function and donor background factors. METHODS: Sixty-five cases of pancreatic transplantation from brain-dead donors, which were performed in our facility, were enrolled in this study. Enrolled recipients underwent a glucagon stimulation test within 1 to 3 months after transplantation to evaluate the pancreatic graft endocrine function with delta C-peptide to compare donor background factors. RESULTS: The following factors were associated with significant deterioration of the delta C-peptide: age of 50 years or greater, death from cerebrovascular accident, hemoglobin A1c level of 5.6% or greater, creatinine level of 1.0 mg/dL or greater, C-reactive protein level of 25 mg/dL or greater, and sodium level of 150 mmol/L or greater. In addition, increased numbers of these donor factors indicated significantly greater deterioration of the posttransplant pancreatic endocrine function ( P < 0.001). CONCLUSIONS: To secure insulin independence after pancreas transplantation, which means maintaining a delta C-peptide level of 1.0 ng/mL or greater on a glucagon stimulation test, the utilization of donors, who possesses more than equal to 3 of the donor factors identified in this study, should be carefully considered.

Impact of the revision of the law on pancreatic transplants in Japan-An analysis of the Japanese Pancreas Transplants Registry.

BACKGROUND: In Japan, it has been about 10 years since the revision of the law on donating brain-dead organs. The present study compared the outcomes of pancreatic transplant before and after the revision of the law. METHODS: The 437 patients who had received pancreas transplantation were divided into two groups according to the time when pancreas transplantation was performed between era 1 (before the revision) and 2 (after the revision), and compared in the patient and pancreas graft survival. RESULTS: While the annual number of brain-dead donors was <10 in era 1, and this number significantly increased in era 2 to >50. This resulted in an increased number of pancreas transplantations: >30 cases per year. The comparison data after a propensity score-matched analysis revealed that the death-censored pancreatic graft survival at 1, 3, and 5 years after pancreas transplantation in era 2 was 94.9%, 92.0%, and 92.0%, which, while lacking significance, tended to be better than the values of 90.5%, 83.1%, and 78.2%, respectively, in era 1. CONCLUSIONS: The revision of the law on donating brain-dead organs increased the number of pancreas transplantations. Technical improvements in surgery due to increased experience with performing pancreas transplants may help improve pancreatic graft survival.

Impact of Pancreas Transplantation on the Patient Survival-An Analysis of the Japanese Pancreas Transplants Registry.

BACKGROUND: The impact of pancreas transplantation, including kidney transplantation on patients' life prognoses, is unclear in Japan. An analysis of the data of the Japan Pancreas Transplant Registry was performed to compare the patient survival between on the waiting list and after pancreas transplantation, and investigate the factors that affect the patient survival after pancreatic transplantation. METHODS: The life prognoses of 361 patients who underwent pancreas transplantation from 2000 to December 2018 were examined. RESULTS: The survival rates at 1, 5, and 10 years on the waiting list were 98.4%, 90.3%, and 78.1%, respectively, while those after transplantation were significantly improved (p = 0.029) at 100%, 97.5%, and 88.9%, respectively. Furthermore, the survival rates of patients waiting for simultaneous pancreas and kidney transplantation (SPK) at 1, 5, and 10 years were 98.2%, 89.4%, and 75.4%, respectively, while those after SPK were also significantly improved (p = 0.026) at 100%, 94.6%, and 88.8%. The multivariable analysis revealed that the duration of diabetes before surgery was the only independent risk factor (hazard ratio = 1.095, p = 0.012) that affected the patient survival after SPK. CONCLUSION: Pancreas transplantation was found to improve the life prognosis of patients with type 1 diabetes, especially those with end-stage renal failure waiting for SPK.

Clinical islet transplantation in Japan.

INTRODUCTION: The results of clinical islet transplantation in Japan are, here in, reported and discussed its efficacy and problems. METHODS: Since the first islet transplantation was performed in 2004, 65 islet isolations and 34 islet transplantations to 18 type 1 diabetic patients have been performed in Japan. RESULTS: Following islet transplantation, patients experienced decreased insulin requirements and lower hemoglobin A1C levels, and positive serum C-peptide levels. All patients achieved stabilized blood glucose levels and the disappearance of hypoglycemic unawareness. Although three patients achieved insulin independency for a limited period, persistent islet graft function was difficult to maintain. Overall islet graft survival was 86.5% at 6 months, 78.7% at 1 year, and 62.9% at 2 years after the first islet transplantation. In our institution, we carried out 23 islet isolations and six islet transplantations to four patients. Although insulin independency was not achieved, all patients showed a disappearance of hypoglycemic unawareness. CONCLUSIONS: Using data from the Japanese Trial of Islet Transplantation, the effectiveness of islet transplantation was shown even when using the pancreata from non-heart-beating donors. Although there are a number of problems to be solved and further improvement is needed, we can state that the introduction of clinical islet transplantation offers hope for type 1 diabetic patients.

The Effects of Using Pancreases Obtained from Brain-Dead Donors for Clinical Islet Transplantation in Japan.

BACKGROUND: The pool of brain-dead donors (BDDs) was increased with the revision to the relevant law in 2010, and islet transplantation from BDDs was started in 2013. The present study assessed the influence of using pancreases from BDDs on islet transplantation in Japan. METHODS: The donor information registered with the secretariat of islet transplants from 2012 was reviewed, and the results of 86 clinical islet isolations performed in Japan between 2003 and 2018 with non-heart-beating donors (NHBDs) (n = 71) and BDDs (n = 15) were investigated. RESULTS: The number of cases for which donor information was registered with the secretariat of islet transplants increased to 1.84 cases/month from 2013 to 2018 in comparison to 1.44/month in 2012, when only NHBDs were used. The median pancreatic islet yield was 275,550 IEQ (Islet equivalents) in the NHBD group but 3,627,000 in the BDD group, which amounted to a statistically significant difference (p = 0.02). As a result, 38/71 cases (53.5%) were achieved successful islet isolation (>5000 IEQ per recipient weight (kg)) was achieved in 38/71 cases (53.5%) in the NHBD group, and 12/15 cases (80.0%) in the BDD group; thus, the rate of successful islet transplantation was higher in the BDD group. CONCLUSION: The use of pancreases from BDDs has increased the overall number of cases for which donor information is registered with the secretariat of islet transplants and has improved the performance of islet isolation, thereby increasing the probability of successfully achieving islet transplantation.