Novel factors potentially initiating acute antibody-mediated rejection in pig kidney xenografts despite an efficient immunosuppressive regimen.

Antibody-mediated rejection (AMR) is a common cause of graft failure after pig-to-nonhuman primate organ transplantation, even when the graft is from a pig with multiple genetic modifications. The specific factors that initiate AMR are often uncertain. We report two cases of pig kidney transplantation into immunosuppressed baboons in which we identify novel factors associated with the initiation of AMR. In the first, membranous nephropathy was the initiating factor that was then associated with the apparent loss of the therapeutic anti-CD154 monoclonal antibody in the urine when severe proteinuria was present. This observation suggests that proteinuria may be associated with the loss of any therapeutic monoclonal antibody, for example, anti-CD154 or eculizumab, in the urine, resulting in xenograft rejection. In the second case, the sequence of events and histopathology tentatively suggested that pyelonephritis may have initiated acute-onset AMR. The association of a urinary infection with graft rejection has been well-documented in ABO-incompatible kidney allotransplantation based on the expression of an antigen on the invading microorganism shared with the kidney graft, generating an immune response to the graft. To our knowledge, these potential initiating factors of AMR in pig xenografts have not been highlighted previously.

Design and testing of a humanized porcine donor for xenotransplantation.

Recent human decedent model studies1,2 and compassionate xenograft use3 have explored the promise of porcine organs for human transplantation. To proceed to human studies, a clinically ready porcine donor must be engineered and its xenograft successfully tested in nonhuman primates. Here we describe the design, creation and long-term life-supporting function of kidney grafts from a genetically engineered porcine donor transplanted into a cynomolgus monkey model. The porcine donor was engineered to carry 69 genomic edits, eliminating glycan antigens, overexpressing human transgenes and inactivating porcine endogenous retroviruses. In vitro functional analyses showed that the edited kidney endothelial cells modulated inflammation to an extent that was indistinguishable from that of human endothelial cells, suggesting that these edited cells acquired a high level of human immune compatibility. When transplanted into cynomolgus monkeys, the kidneys with three glycan antigen knockouts alone experienced poor graft survival, whereas those with glycan antigen knockouts and human transgene expression demonstrated significantly longer survival time, suggesting the benefit of human transgene expression in vivo. These results show that preclinical studies of renal xenotransplantation could be successfully conducted in nonhuman primates and bring us closer to clinical trials of genetically engineered porcine renal grafts.

Selective Bcl-2 inhibition promotes hematopoietic chimerism and allograft tolerance without myelosuppression in nonhuman primates.

Hematopoietic stem cell transplantation (HSCT) has many potential applications beyond current standard indications, including treatment of autoimmune disease, gene therapy, and transplant tolerance induction. However, severe myelosuppression and other toxicities after myeloablative conditioning regimens have hampered wider clinical use. To achieve donor hematopoietic stem cell (HSC) engraftment, it appears essential to establish niches for the donor HSCs by depleting the host HSCs. To date, this has been achievable only by nonselective treatments such as irradiation or chemotherapeutic drugs. An approach that is capable of more selectively depleting host HSCs is needed to widen the clinical application of HSCT. Here, we show in a clinically relevant nonhuman primate model that selective inhibition of B cell lymphoma 2 (Bcl-2) promoted hematopoietic chimerism and renal allograft tolerance after partial deletion of HSCs and effective peripheral lymphocyte deletion while preserving myeloid cells and regulatory T cells. Although Bcl-2 inhibition alone was insufficient to induce hematopoietic chimerism, the addition of a Bcl-2 inhibitor resulted in promotion of hematopoietic chimerism and renal allograft tolerance despite using only half of the dose of total body irradiation previously required. Selective inhibition of Bcl-2 is therefore a promising approach to induce hematopoietic chimerism without myelosuppression and has the potential to render HSCT more feasible for a variety of clinical indications.

TNX-1500, a crystallizable fragment-modified anti-CD154 antibody, prolongs nonhuman primate renal allograft survival.

The blockade of the CD154-CD40 pathway with anti-CD154 monoclonal antibody has been a promising immunomodulatory approach to prevent allograft rejection. However, clinical trials of immunoglobulin G1 antibodies targeting this pathway revealed thrombogenic properties, which were subsequently shown to be mediated by crystallizable fragment (Fc)-gamma receptor IIa-dependent platelet activation. To prevent thromboembolic complications, an immunoglobulin G4 anti-CD154 monoclonal antibody, TNX-1500, which retains the fragment antigen binding region of ruplizumab (humanized 5c8, BG9588), was modified by protein engineering to decrease Fc binding to Fc-gamma receptor IIa while retaining certain other effector functions and pharmacokinetics comparable with natural antibodies. Here, we report that TNX-1500 treatment is not associated with platelet activation in vitro and consistently inhibits kidney allograft rejection in vivo without clinical or histologic evidence of prothrombotic phenomena. We conclude that TNX-1500 retains efficacy similar to that of 5c8 to prevent kidney allograft rejection while avoiding previously identified pathway-associated thromboembolic complications.

Short-term outcomes of second kidney transplantation compared with those of first transplantation in Japanese patients: a single-center, retrospective, observational study.

BACKGROUND: Among patients who undergo kidney transplantation, a subsequent second kidney transplantation (TX2) is often necessary. The TX2 outcomes remain controversial, however, and only limited data are available on clinical outcomes of TX2 in Japanese patients. This study aimed to assess graft and patient survival rates of TX2 and compared these rates with those of first kidney transplantation (TX1) in Japanese patients. METHODS: Of the 898 kidney transplantations performed between 2010 and 2019 at our institution, 33 were TX2. We performed survival analysis using weighted Kaplan-Meier analysis and Cox proportional hazards analysis with propensity score matching, specifically inverse probability of treatment weighting (IPTW). RESULTS: Death-censored graft survival (DCGS) rates at 1, 3, and 5 years for the TX1 versus TX2 groups were 99.3, 97.9, and 95.0% versus 100, 96.0, and 91.2%, respectively. Overall survival (OS) rates at 1, 3, and 5 years for the TX1 versus TX2 groups were 99.4, 98.9, and 97.8% versus 100, 100, and 94.4%, respectively. Using the log-rank test, IPTW-weighted Kaplan-Meier curves showed no significant differences for TX1 versus TX2 in DCGS (p = 0.535) and OS (p = 0.302). On Cox proportional hazards analysis for TX2 versus TX1, the IPTW-adjusted hazard ratio (HR) for DCGS was 1.75 (95% CI, 0.28-10.9; p = 0.550) and for OS was 2.71 (95% CI, 0.40-18.55; p = 0.311). CONCLUSIONS: For patients who require TX2, this treatment is an acceptable option based on the short-term outcomes data for DCGS and OS.

Hand port-site infection after hand-assisted laparoscopic donor nephrectomy for living-donor kidney transplantation: a retrospective cohort study.

Background: Hand-assisted laparoscopic donor nephrectomy (HALDN) is widely performed to minimize burden on living kidney donors. However, hand port-site infections after HALDN may occur. This study aimed to assess the impact of donor characteristics including preoperative comorbidities and operative factors on hand port-site infection after HALDN. Methods: In this single-center, retrospective cohort study, 1,260 consecutive HALDNs for living-donor kidney transplantation performed between January 2008 and December 2021 were evaluated. All living donors met the living kidney donor guidelines in Japan. Hand port-site infections were identified in 88 HALDN cases (7.0%). To investigate risk factors for hand port-site infection, donor characteristics including preoperative comorbidities such as hypertension, glucose intolerance, dyslipidemia, obesity, and operative factors such as operative duration, blood loss, preoperative antibiotic prophylaxis, and prophylactic subcutaneous suction drain placement at the hand port-site were analyzed using logistic regression analysis. Results: In the multivariate analysis, significant differences were identified regarding sex (P = 0.021; odds ratio [OR], 1.971; 95% confidence interval [CI], 1.108-3.507), preoperative antibiotic prophylaxis (P < 0.001; OR, 0.037; 95% CI [0.011-0.127]), and prophylactic subcutaneous suction drain placement at the hand port-site (P = 0.041; OR, 2.005; 95% CI [1.029-3.907]). However, a significant difference was not identified regarding glucose intolerance (P = 0.572; OR, 1.148; 95% CI [0.711-1.856]). Preoperative comorbidities may not cause hand port-site infections within the donors who meet the living kidney donor guidelines. Preoperative antibiotic prophylaxis is crucial in preventing hand port-site infection, whereas prophylactic subcutaneous suction drain placement may increase the risk of hand port-site infection.

Renal hyperparathyroidism.

The number of the patients with chronic kidney disease is now increasing in the world. The pathophysiology of renal hyperparathyroidism is closely associated with Klotho-FGF-endocrine axes, which must be solved definitively as early as possible. It was revealed that the expression of fgf23 is activated by calciprotein particles, which induces vascular ossification. And it is well known that phosphorus overload directly increases parathyroid hormone and hyperparathyroid bone disease develops in those subjects. On the other hand, low turnover bone disease is often recently. Both the patients with chronic kidney disease suffering from hyperparathyroid bone disease or low turnover bone disease are associated with increased fracture risk. Micropetrosis may be one of the causes of increased fracture risk in the subjects with low turnover bone disease. In this chapter, we now describe the diagnosis, pathophysiology and treatments of renal hyperparathyroidism.

Risk factors for subchondral insufficiency fracture of the femoral head in renal transplant patients.

INTRODUCTION: Risk factors associated with subchondral insufficiency fracture (SIF) of the femoral head have not been established. The aim of the present study was to determine the incidence and risk factors for SIF of the femoral head following renal transplantation (RT). MATERIALS AND METHODS: We analyzed the cases of 681 RT patients (mean age at surgery: 49.5 ± 13.6 years, 249 women, 432 men) to determine the incidence of SIF. Hip magnetic resonance imaging (MRI) was performed 6 months post-RT. The following potential predictors of SIF were evaluated: (1) patient's condition at RT: bone mineral density (BMD), pre-RT laboratory values including calcium (Ca), phosphorus (P), calcium-phosphorus product (Ca × P), and intact parathyroid hormone; the patient and donor's blood relationship; and mismatching number of human leukocyte antigens (HLAs), and (2) post-RT dosage(s) of steroid(s), the immunosuppressive regimen, and the incidence of acute rejection. RESULTS: SIF was observed in 15 hips (13 patients, 1.9%). We successfully matched 39 patients without SIF. A multivariate logistic regression analysis adjusted for cumulative dosages of steroids, revealed the following were risk factors for SIF: osteoporosis (OR: 11.4, p = 0.046), lumbar BMD (OR: 0.003, p = 0.038), pre-RT serum P (OR 2.68, p = 0.004), and pre-RT serum Ca × P (OR: 1.11, p = 0.005). CONCLUSION: Since osteoporosis, the lumbar BMD, serum P, and serum Ca × P were identified as risk factors for a post-RT SIF, these factors should be evaluated before RT for the prediction of the SIF risk.

Elevated parathyroid hormone one year after kidney transplantation is an independent risk factor for graft loss even without hypercalcemia.

BACKGROUND: Hypercalcemic hyperparathyroidism has been associated with poor outcomes after kidney transplantation (KTx). However, the clinical implications of normocalcemic hyperparathyroidism after KTx are unclear. This retrospective cohort study attempted to identify these implications. METHODS: Normocalcemic recipients who underwent KTx between 2000 and 2016 without a history of parathyroidectomy were included in the study. Those who lost their graft within 1 year posttransplant were excluded. Normocalcemia was defined as total serum calcium levels of 8.5-10.5 mg/dL, while hyperparathyroidism was defined as when intact parathyroid hormone levels exceeded 80 pg/mL. The patients were divided into two groups based on the presence of hyperparathyroidism 1 year after KTx. The primary outcome was the risk of graft loss. RESULTS: Among the 892 consecutive patients, 493 did not have hyperparathyroidism (HPT-free group), and 399 had normocalcemic hyperparathyroidism (NC-HPT group). Ninety-five patients lost their grafts. Death-censored graft survival after KTx was significantly lower in the NC-HPT group than in the HPT-free group (96.7% vs. 99.6% after 5 years, respectively, P < 0.001). Cox hazard analysis revealed that normocalcemic hyperparathyroidism was an independent risk factor for graft loss (P = 0.002; hazard ratio, 1.94; 95% confidence interval, 1.27-2.98). CONCLUSIONS: Normocalcemic hyperparathyroidism 1 year after KTx was an independent risk factor for death-censored graft loss. Early intervention of elevated parathyroid hormone levels may lead to better graft outcomes, even without overt hypercalcemia.

Preservation of the nonrecurrent laryngeal nerve using intraoperative nerve monitoring during endoscopic thyroidectomy.

A 40-year-old woman underwent right lobe thyroidectomy for thyroid nodules that increased in size from 17 mm to 33.5 mm within 1 year. Identification of arteria lusoria using computed tomography suggested the presence of a right nonrecurrent laryngeal nerve (RNRLN). Endoscopic thyroidectomy was performed under general anesthesia. The right vagal nerve was first identified between the common carotid artery and jugular vein. A positive response was confirmed via intraoperative neuromonitoring (IONM), implying that the RNRLN did not branch from the central side of the stimulated point of the vagal nerve. The RNRLN was confirmed using IONM around the middle to lower pole of the right thyroid gland. The right thyroid lobe was successfully removed, with meticulous preservation of the RNRLN. The motion of the vocal cord, examined by an ear-nose-throat doctor postoperatively, was intact. We demonstrated the efficacy of IONM in patients with RNRLN who underwent endoscopic thyroidectomy.

Two-year outcomes of low-exposure extended-release tacrolimus and mycophenolate mofetil regimen in de novo kidney transplantation: A multi-center randomized controlled trial.

BACKGROUND: Once-daily extended-release tacrolimus (TACER) is commonly administered following kidney transplantation (KTx); however, its optimal dosage remains unknown. METHODS: In this multi-center, randomized controlled trial, 62 living donor KTx recipients were assigned to either standard-exposure (SE; n = 32) or low-exposure (LE; n = 30) TACER (Graceptor®, Astellas Pharm Inc.) groups. All patients received basiliximab and mycophenolate mofetil (MMF). The primary outcomes were acute rejection, graft/patient survival, and the secondary outcomes were incidence of cytomegalovirus infection, and de novo donor-specific antibodies (dnDSA) production. RESULTS: The tacrolimus trough level and estimated area under the blood concentration-time curve (eAUC) were significantly higher in SE than in LE (SE vs. LE; 1 year: 5.0 ± 0.9 ng/ml and 206.9 ± 26.8 ng h/ml vs. 3.4 ± 1.0 ng/ml and 153.9 ± 26.4 ng h/ml; 2 years: 4.8 ± 1.0 ng/ml and 204.9 ± 30.1 ng h/ml vs. 3.8 ± 0.9 ng/ml and 164.4 ± 27.0 ng h/ml). In contrast, the dosage and eAUC of MMF did not differ between groups. Two-year graft and patient survival rates were 100% in both groups, and acute rejection rates were 0% and 10% in the SE and LE, respectively (p = 0.11). The mean estimated glomerular filtration rates did not differ between the groups. Cytomegalovirus infection was slightly lower in the LE (SE: 12.5% and LE: 6.7%, p = 0.37). In the LE, four cases of dnDSA were noted within 2 years of transplantation; no case was observed in the SE (p = 0.034). CONCLUSIONS: Although the LE TACER regimen showed similar rates of acute rejection, as well as graft and patient survival compared with SE after KTx, LE was significantly more associated with dnDSA. Further investigation of its long-term effect on graft survival is warranted. (University Hospital Medical Information Network Clinical Trials Registry ID: UMIN000033089).

Cholecalciferol Supplementation Attenuates Bone Loss in Incident Kidney Transplant Recipients: A Prespecified Secondary Endpoint Analysis of a Randomized Controlled Trial.

Vitamin D deficiency, persistent hyperparathyroidism, and bone loss are common after kidney transplantation (KTx). However, limited evidence exists regarding the effects of cholecalciferol supplementation on parathyroid hormone (PTH) and bone loss after KTx. In this prespecified secondary endpoint analysis of a randomized controlled trial, we evaluated changes in PTH, bone metabolic markers, and bone mineral density (BMD). At 1 month post-transplant, we randomized 193 patients to an 11-month intervention with cholecalciferol (4000 IU/d) or placebo. The median baseline 25-hydroxyvitamin D (25[OH]D) level was 10 ng/mL and 44% of participants had osteopenia or osteoporosis. At the end of the study, the median 25(OH)D level was increased to 40 ng/mL in the cholecalciferol group and substantially unchanged in the placebo group. Compared with placebo, cholecalciferol significantly reduced whole PTH concentrations (between-group difference of -15%; 95% confidence interval [CI] -25 to -3), with greater treatment effects in subgroups with lower 25(OH)D, lower serum calcium, or higher estimated glomerular filtration rate (pint < 0.05). The percent change in lumbar spine (LS) BMD from before KTx to 12 months post-transplant was -0.2% (95% CI -1.4 to 0.9) in the cholecalciferol group and -1.9% (95% CI -3.0 to -0.8) in the placebo group, with a significant between-group difference (1.7%; 95% CI 0.1 to 3.3). The beneficial effect of cholecalciferol on LS BMD was prominent in patients with low bone mass pint < 0.05). Changes in serum calcium, phosphate, bone metabolic markers, and BMD at the distal radius were not different between groups. In mediation analyses, change in whole PTH levels explained 39% of treatment effects on BMD change. In conclusion, 4000 IU/d cholecalciferol significantly reduced PTH levels and attenuated LS BMD loss after KTx. This regimen has the potential to eliminate vitamin D deficiency and provides beneficial effects on bone health even under glucocorticoid treatment. © 2021 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).

Oral/oesophageal candidiasis is a risk factor for severe infection after kidney transplantation.

AIM: Bacterial and fungal infections are serious, life-threatening conditions after kidney transplantation. The development of oral/oesophageal candidiasis after kidney transplantation is not a reported risk factor for subsequent severe infection. This study was performed to investigate the relationship between oral/oesophageal candidiasis after kidney transplantation and the development of subsequent infection requiring hospitalization. METHODS: This retrospective study included 522 consecutive patients who underwent kidney transplantation at Japanese Red Cross Aichi Medical Center Nagoya Daini Hospital from 1 January 2010 to 1 February 2019. Ninety-five percentage of patients were living donor transplant recipients. Visual examination was performed to detect oral candidiasis, beginning immediately after kidney transplantation; upper gastrointestinal endoscopy was performed 8-10 months after kidney transplantation. Twenty-five patients developed candidiasis (Candida-onset group) and 497 did not (non-Candida-onset group). The follow-up periods were 67 (37-86) months in the Candida-onset group and 55 (34-89) months in the non-Candida-onset group. Severe infection was defined as bacterial or fungal infection requiring hospitalization; viral infections were excluded. RESULTS: Severe infection developed in 9/25 (36%) patients in the Candida-onset group and in 77/497 (15%) patients in the non-Candida-onset group (p = .006). Binomial logistic analysis revealed that Candida infection (odds ratio [OR] 2.53, 95% confidence interval [CI] 1.06-6.06; p = .037) and use of rituximab (OR 1.81, 95% CI 1.12-2.93; p = .016) were significant predictors of subsequent severe infection. CONCLUSION: Oral/oesophageal candidiasis is a risk factor for severe infection after kidney transplantation and suggests an over-immunosuppressive state, which should prompt evaluation of immunosuppression.

Adult Living-Donor Kidney Transplantation, Donor Age, and Donor-Recipient Age.

INTRODUCTION: Owing to organ shortage, the number of kidney transplantation (KT) involving older adult living donors is increasing. We aimed to investigate the effects of living-donor age and donor-recipient age differences on KT outcomes. METHODS: This single-center, retrospective cohort study involved 853 adult LDKTs performed between January 2008 and December 2018. Recipients were stratified into the following 5 groups based on donor age and donor-recipient age difference: donor age, 30 to 49 years and age difference, -10 to 15 years; donor age, 50 to 69 years and age difference, -10 to 15 years; donor age, 50 to 69 years and age difference, 15 to 40 years; donor age, 70 to 89 years and age difference, -10 to 15 years; and donor age, 70 to 89 years and age difference, 15 to 40 years (groups 1, 2, 3, 4, and 5, respectively). As a primary outcome, the risk of graft loss was investigated. The secondary outcomes were postoperative estimated glomerular filtration rates (eGFRs) and mortality rates of recipients. RESULTS: Group 4, representing KT between older adult donors and older adult recipients, had the highest graft loss risk and mortality. The eGFRs of the recipients from donors aged 70 to 89 years (groups 4 and 5) were significantly lower than those from donors in the other groups. Although the differences in the eGFR between groups 4 and 5 were not significant, the eGFR of group 4 was lower than that of group 5 at 6 months post-KT. CONCLUSION: LDKTs from older adult donors to older adult recipients resulted in the worst graft survival and mortality rates.

T-Cell Epitopes Shared Between Immunizing HLA and Donor HLA Associate With Graft Failure After Kidney Transplantation.

CD4+ T-helper cells play an important role in alloimmune reactions following transplantation by stimulating humoral as well as cellular responses, which might lead to failure of the allograft. CD4+ memory T-helper cells from a previous immunizing event can potentially be reactivated by exposure to HLA mismatches that share T-cell epitopes with the initial immunizing HLA. Consequently, reactivity of CD4+ memory T-helper cells toward T-cell epitopes that are shared between immunizing HLA and donor HLA could increase the risk of alloimmunity following transplantation, thus affecting transplant outcome. In this study, the amount of T-cell epitopes shared between immunizing and donor HLA was used as a surrogate marker to evaluate the effect of donor-reactive CD4+ memory T-helper cells on the 10-year risk of death-censored kidney graft failure in 190 donor/recipient combinations using the PIRCHE-II algorithm. The T-cell epitopes of the initial theoretical immunizing HLA and the donor HLA were estimated and the number of shared PIRCHE-II epitopes was calculated. We show that the natural logarithm-transformed PIRCHE-II overlap score, or Shared T-cell EPitopes (STEP) score, significantly associates with the 10-year risk of death-censored kidney graft failure, suggesting that the presence of pre-transplant donor-reactive CD4+ memory T-helper cells might be a strong indicator for the risk of graft failure following kidney transplantation.

Predictors of Bone Mineral Density Improvement after Parathyroidectomy for Secondary Hyperparathyroidism: A Retrospective Single-Center Analysis.

BACKGROUND: Parathyroidectomy (PTx) reportedly increases bone mineral density (BMD) in patients with severe secondary hyperparathyroidism (SHPT). To date, however, there has not been sufficient evidence on predictors of BMD improvement post-PTx for SHPT, an issue the present retrospective cohort study aimed to address. METHODS: A total of 173 SHPT patients who underwent total PTx with forearm autograft between 2009 and 2017 were included in the present study. Demographic information, perioperative laboratory data and pre- and post-PTx BMD values (measured by dual-energy X-ray absorptiometry) were collected from their medical records. The change in BMD post-PTx in the lumbar spine was evaluated as the primary outcome. Then, a multivariate logistic regression analysis was performed for a ≥ 10% increase in BMD post-PTx. RESULTS: Overall, the median BMD in the lumbar spine was increased by 8.7% post-PTx. The multivariate logistic regression analysis revealed that age ≥ 70 years (P = 0.005; odds ratio [OR], 0.138; 95% confidence interval [CI]: 0.034-0.555), serum Ca level (P = 0.017; OR, 0.598; 95% CI: 0.392-0.911) and pre-PTx BMD in the lumbar spine (P = 0.003; OR, 0.013; 95% CI: 0.001-0.229) were negatively associated with a ≥ 10% increase in BMD post-PTx. CONCLUSION: Our study demonstrated that presurgical age, serum Ca levels and BMD values could better predict an improvement in BMD post-PTx in SHPT patients.

Intact parathyroid hormone levels localize causative glands in persistent or recurrent renal hyperparathyroidism: A retrospective cohort study.

Persistent or recurrent renal hyperparathyroidism may occur after total parathyroidectomy and transcervical thymectomy with forearm autograft under continuous stimulation due to uremia. Parathyroid hormone (PTH) levels may reflect persistent or recurrent renal hyperparathyroidism because of the enlarged autografted parathyroid glands in the forearm or remnant parathyroid glands in the neck or mediastinum. Detailed imaging requires predictive localization of causative parathyroid glands. Casanova and simplified Casanova tests may be convenient. However, these methods require avascularization of the autografted forearm for >10 min with a tourniquet or Esmarch. The heavy pressure during avascularization can be incredibly painful and result in nerve damage. An easier method that minimizes the burden on patients in addition to predicting the localization of causative parathyroid glands was developed in this study. Ninety patients who underwent successful re-parathyroidectomy for persistent or recurrent renal hyperparathyroidism after parathyroidectomy between January 2000 and July 2019 were classified according to the localization of causative parathyroid glands (63 and 27 patients in the autografted forearm and the neck or mediastinum groups, respectively). Preoperatively, intact PTH levels were measured from bilateral forearm blood samples following a 5-min avascularization of the autografted forearm. Cutoff values of the intact PTH ratio (intact PTH level obtained from the non-autografted forearm before re-parathyroidectomy/intact PTH level obtained from the autografted forearm before re-parathyroidectomy) were investigated with receiver operating characteristic curves to localize the causative parathyroid glands. Intact PTH ratios of <0.310 with an area under the curve (AUC) of 0.913 (95% confidence interval [CI]: 0.856-0.970; P < 0.001) and >0.859 with an AUC 0.744 (95% CI: 0.587-0.901; P = 0.013) could predict causative parathyroid glands in the autografted forearm and the neck or mediastinum with diagnostic accuracies of 81.1% and 83.3%, respectively. Therefore, we propose that the intact PTH ratio is useful for predicting the localization of causative parathyroid glands for re-parathyroidectomy.

Clinical Significance of Shared T Cell Epitope Analysis in Early De Novo Donor-Specific Anti-HLA Antibody Production After Kidney Transplantation and Comparison With Shared B cell Epitope Analysis.

In pre-sensitizing events, immunological memory is mainly created via indirect allorecognition where CD4+ T cells recognize foreign peptides in the context of self-HLA class II (pHLA) presented on antigen-presenting cells. This recognition makes it possible for naive CD4+ T-helper cells to differentiate into memory cells, resulting in the creation of further antibody memory. These responses contribute to effective secretion of donor-specific anti-HLA antibodies (DSA) after second encounters with the same peptide. Preformed donor-reactive CD4+ memory T cells may induce early immune responses after transplantation; however, the tools to evaluate them are limited. This study evaluated shared T cell epitopes (TEs) between the pre-sensitizing and donor HLA using an in silico assay, an alternative to estimate donor-reactive CD4+ memory T cells before transplantation. In 578 living donor kidney transplants without preformed DSA, 69 patients had anti-HLA antibodies before transplantation. Of them, 40 had shared TEs and were estimated to have donor-reactive CD4+ memory T cells. De novo DSA formation in the early phase was significantly higher in the shared TE-positive group than in the anti-HLA antibody- and shared TE-negative groups (p=0.001 and p=0.02, respectively). In conclusion, evaluation of shared TEs for estimating preformed donor-reactive CD4+ memory T cells may help predict the risk of early de novo DSA formation after kidney transplantation.

Hand-Assisted Laparoscopic Donor Nephrectomy in Living Donors with a History of Abdominal Surgery: A Retrospective Cohort Study.

BACKGROUND Hand-assisted laparoscopic donor nephrectomy (HALDN) is frequently performed in living kidney transplantation donors. This study investigated the efficacy and safety of HALDN for living donors with abdominal surgical histories. MATERIAL AND METHODS A total of 573 living kidney donors underwent donor nephrectomies for living donor kidney transplantation between January 2008 and May 2015. Eighteen donors underwent open donor nephrectomy and were excluded from analyses. Left HALDN was performed in 533 donors, including 44 donors with abdominal surgical histories and 489 donors without abdominal surgical histories. Right HALDN was performed in 22 donors, including 11 donors with abdominal surgical histories and 11 donors without abdominal surgical histories. Graft quality including the lengths of arteries, veins and ureters, time to initial urination, recipient complications, and recipient estimated glomerular filtration rate (eGFR) and operation quality including warm ischemic time, blood loss, operation duration, donor complications and donor eGFR, were compared between donors with and without abdominal surgical histories in the left and right HALDN groups. RESULTS The metrics of graft and operation quality were similar between living kidney donors with and without a history of abdominal surgery who underwent left or right HALDN. CONCLUSIONS The efficacy and safety of HALDN were not impaired by abdominal surgical histories.

Intraoperative recurrent laryngeal nerve monitoring using endotracheal electromyography during parathyroidectomy for secondary hyperparathyroidism.

OBJECTIVE: To investigate the factors associated with adherence of an enlarged parathyroid gland to the recurrent laryngeal nerve (RLN) and the effectiveness of intraoperative neural monitoring (IONM). METHODS: This single-center retrospective study involved samples from 197 consecutive patients (394 RLNs; 733 parathyroid glands) who underwent parathyroidectomy and transcervical thymectomy between September 2010 and December 2014. The presence of parathyroid gland adhesion to the RLN and the clinical characteristics of patients with and without nerve adhesion were recorded. All patients underwent intraoperative monitoring of the electromyographic responses of the vocal cords using the endotracheal NIM-Response 3.0 system. The patients' postoperative clinical outcomes were recorded. RESULTS: Parathyroid gland adhesion to the RLN was significantly associated with maximum gland diameter (>15 mm), weight (>500 mg), and the presence of nodular hyperplasia. IONM demonstrated a sensitivity of 97.8%, specificity of 43.5%, and accuracy of 94.7% for detecting nerve damage. Parathyroid gland adhesion to 17 RLNs occurred in 3 cases (17.6%) of vocal cord paralysis, whereas the 377 glands without nerve adhesion resulted in vocal cord paralysis in 20 cases (5.3%). CONCLUSION: Our findings demonstrated the effectiveness of IONM using endotracheal electromyography in patients who underwent parathyroidectomy for secondary hyperparathyroidism.