Impact of Age 70 years or Older on Donors for Living-Donor Kidney Transplantation.

Introduction: Kidney transplantation (KT) involving elderly living kidney donors (LKDs) is becoming more frequent because of a profound organ shortage. The efficacy of KT involving grafts obtained from LKDs aged 70 years or older has been reported. However, the safety of donor nephrectomy in LKDs aged 70 years or older, including that associated with changes in the estimated glomerular filtration rate (eGFR), has not been investigated. This study investigated the outcomes of LKDs aged 70 years or older after donor nephrectomy. Methods: This single-center, retrospective cohort study included 1226 LKDs who underwent donor nephrectomy between January 2008 and December 2020. LKDs were stratified into the following age groups: 30 to 49 years (244 LKDs), 50 to 69 years (803 LKDs), and 70 to 89 years (179 LKDs). Surgical outcomes, postoperative eGFR changes, end-stage renal disease (ESRD) rates, and mortality rates were compared among these groups. Results: No significant difference in surgical outcomes was identified among the groups. LKDs aged 70 to 89 years experienced the lowest eGFR changes at all time points and the lowest eGFR improvement; however, ESRD was not identified in any group during the observation period. Mortality was the highest among LKDs aged 70 to 89 years compared to the other age groups. Conclusion: Surgical outcomes, eGFR changes, and ESRD incidences can support the safety of donor nephrectomy in LKDs aged 70 years or older. Considering the advanced age, the high mortality rates in LKDs aged 70 years or older could be considered acceptable.

Pre-Transplant Calcimimetic Use and Dose Information Improves the Accuracy of Prediction of Tertiary Hyperparathyroidism after Kidney Transplantation: A Retrospective Cohort Study.

Tertiary hyperparathyroidism (THPT) is characterized by elevated parathyroid hormone and serum calcium levels after kidney transplantation (KTx). To ascertain whether pre-transplant calcimimetic use and dose information would improve THPT prediction accuracy, this retrospective cohort study evaluated patients who underwent KTx between 2010 and 2022. The primary outcome was the development of clinically relevant THPT. Logistic regression analysis was used to evaluate pre-transplant calcimimetic use as a determinant of THPT development. Participants were categorized into four groups according to calcimimetic dose, developing two THPT prediction models (with or without calcimimetic information). Continuous net reclassification improvement (CNRI) and integrated discrimination improvement (IDI) were calculated to assess ability to reclassify the degree of THPT risk by adding pre-transplant calcimimetic information. Of the 554 patients, 87 (15.7%) developed THPT, whereas 139 (25.1%) received pre-transplant calcimimetic treatment. Multivariate logistic regression analysis revealed that pre-transplant calcimimetic use was significantly associated with THPT development. Pre-transplant calcimimetic information significantly improved the predicted probability accuracy of THPT (CNRI and IDI were 0.91 [p < 0.001], and 0.09 [p < 0.001], respectively). The THPT prediction model including pre-transplant calcimimetic information as a predictive factor can contribute to the prevention and early treatment of THPT in the era of calcimimetics.

Lung cancer after kidney transplantation: a 50-year experience at a single institution.

PURPOSE: To investigate the clinical characteristics of lung cancer that develops after kidney transplantation. METHODS: The clinical data of patients with lung cancer diagnosed after kidney transplantation were collected retrospectively. The medical records were extracted from our database. All patients underwent routine chest examination after kidney transplantation. RESULTS: In total, 17 lung tumors were detected in 15 (0.6%) of 2593 patients who underwent kidney transplantation at our institution. Eleven lung tumors were completely resected from a collective 10 patients (surgical group). The remaining five patients did not receive surgical treatment (nonsurgical group). The surgical group underwent wedge resection (n = 5), segmentectomy (n = 1), lobectomy (n = 3), and bilobectomy (n = 1). The pathological stages were 0 (n = 1), IA1 (n = 2), IA2 (n = 4), IA3 (n = 2), and IB (n = 1). The surgical group had a significantly better prognosis than the nonsurgical group. There were no perioperative complications related to kidney transplantation in either group. CONCLUSIONS: Routine chest examination would be useful for the early diagnosis and treatment of lung cancer after kidney transplantation. Moreover, surgical resection for early-stage lung cancer was associated with a better prognosis for kidney transplantation patients.

Prediction models for the recipients' ideal perioperative estimated glomerular filtration rates for predicting graft survival after adult living-donor kidney transplantation.

Introduction: The impact of the perioperative estimated glomerular filtration rate (eGFR) on graft survival in kidney transplant recipients is yet to be evaluated. In this study, we developed prediction models for the ideal perioperative eGFRs in recipients. Methods: We evaluated the impact of perioperative predicted ideal and actual eGFRs on graft survival by including 1,174 consecutive adult patients who underwent living-donor kidney transplantation (LDKT) between January 2008 and December 2020. Prediction models for the ideal perioperative eGFR were developed for 676 recipients who were randomly assigned to the training and validation sets (ratio: 7:3). The prediction models for the ideal best eGFR within 3 weeks and those at 1, 2, and 3 weeks after LDKT in 474 recipients were developed using 10-fold validation and stepwise multiple regression model analyzes. The developed prediction models were validated in 202 recipients. Finally, the impact of perioperative predicted ideal eGFRs/actual eGFRs on graft survival was investigated using Fine-Gray regression analysis. Results: The correlation coefficients of the predicted ideal best eGFR within 3 weeks and the predicted ideal eGFRs at 1, 2, and 3 weeks after LDKT were 0.651, 0.600, 0.598, and 0.617, respectively. Multivariate analyzes for graft loss demonstrated significant differences in the predicted ideal best eGFR/actual best eGFR within 3 weeks and the predicted ideal eGFRs/actual eGFRs at 1, 2, and 3 weeks after LDKT. Discussion: The predicted ideal best eGFR/actual best eGFR within 3 weeks and the predicted ideal eGFRs/actual eGFRs at 1, 2, and 3 weeks after LDKT were independent prognostic factors for graft loss. Therefore, the perioperative predicted ideal eGFR/actual eGFR may be useful for predicting graft survival after adult LDKT.

Maximal parathyroid gland diameter as a predictive factor for autograft-dependent recurrent secondary hyperparathyroidism after total parathyroidectomy.

Introduction: Following total parathyroidectomy (PTx), transcervical thymectomy, and forearm autograft for secondary hyperparathyroidism (SHPT), recurrent SHPT can occur in the autografted forearm. However, few studies have investigated the factors contributing to re-PTx due to autograft-dependent recurrent SHPT before the completion of the initial PTx. Methods: A total of 770 patients who had autografted parathyroid fragments derived from only one of the resected parathyroid glands (PTGs) and who had undergone successful initial total PTx and transcervical thymectomy-defined by serum intact parathyroid hormone level < 60 pg/mL on postoperative day 1-between January 2001 and December 2022 were included in this retrospective cohort study. Factors contributing to re-PTx due to graft-dependent recurrent SHPT before the completion of the initial PTx were investigated using multivariate Cox regression analysis. Receiver operating characteristic (ROC) curve analysis was performed to obtain the optimal maximum diameter of PTG for autograft. Results: Univariate analysis showed that dialysis vintage and maximum diameter and weight of the PTG for autograft were significant factors contributing to graft-dependent recurrent SHPT. However, multivariate analysis revealed that dialysis vintage (P=0.010; hazard ratio [HR], 0.995; 95% confidence interval [CI], 0.992-0.999) and the maximum diameter of the PTG for autograft (P=0.046; HR, 1.107; 95% CI, 1.002-1.224) significantly contributed to graft-dependent recurrent SHPT. ROC curve analysis showed that < 14 mm was the optimal maximum diameter of PTG for autograft (area under the curve, 0.628; 95% CI, 0.551-0.705). Conclusions: The dialysis vintage and maximum diameter of PTG for autograft may contribute to re-PTx due to autograft-dependent recurrent SHPT, which can be prevented by using PTGs with a maximum diameter of < 14 mm for autograft.

Persistent hyperparathyroidism after preemptive kidney transplantation.

BACKGROUND: Long-term dialysis vintage is a predictor of persistent hyperparathyroidism (HPT) after kidney transplantation (KTx). Recently, preemptive kidney transplantation (PKT) has increased. However, the incidence, predictors, and clinical implications of HPT after PKT are unclear. Here, we aimed to elucidate these considerations. METHODS: In this retrospective cohort study, we enrolled patients who underwent PKT between 2000 and 2016. Those who lost their graft within 1 year posttransplant were excluded. HPT was defined as an intact parathyroid hormone (PTH) level exceeding 80 pg/mL or hypercalcemia unexplained by causes other than HPT. Patients were divided into two groups based on the presence of HPT 1 year after PKT. The primary outcome was the predictors of HPT after PKT, and the secondary outcome was graft survival. RESULTS: Among the 340 consecutive patients who underwent PKT, 188 did not have HPT (HPT-free group) and 152 had HPT (HPT group). Multivariate logistic regression analysis revealed that pretransplant PTH level (P < 0.001; odds ratio [OR], 5.480; 95% confidence interval [CI], 2.070-14.50) and preoperative donor-estimated glomerular filtration rate (P = 0.033; OR, 0.978; 95% CI, 0.957-0.998) were independent predictors of HPT after PKT. Death-censored graft survival was significantly lower in the HPT group than that in the HPT-free group (90.4% vs. 96.4% at 10 years, P = 0.009). CONCLUSIONS: Pretransplant PTH levels and donor kidney function were independent predictors of HPT after PKT. In addition, HPT was associated with worse graft outcomes even after PKT.

Treatment for secondary hyperparathyroidism focusing on parathyroidectomy.

Secondary hyperparathyroidism (SHPT) is a major problem for patients with chronic kidney disease and can cause many complications, including osteodystrophy, fractures, and cardiovascular diseases. Treatment for SHPT has changed radically with the advent of calcimimetics; however, parathyroidectomy (PTx) remains one of the most important treatments. For successful PTx, removing all parathyroid glands (PTGs) without complications is essential to prevent persistent or recurrent SHPT. Preoperative imaging studies for the localization of PTGs, such as ultrasonography, computed tomography, and 99mTc-Sestamibi scintigraphy, and intraoperative evaluation methods to confirm the removal of all PTGs, including, intraoperative intact parathyroid hormone monitoring and frozen section diagnosis, are useful. Functional and anatomical preservation of the recurrent laryngeal nerves can be confirmed via intraoperative nerve monitoring. Total or subtotal PTx with or without transcervical thymectomy and autotransplantation can also be performed. Appropriate operative methods for PTx should be selected according to the patients' need for kidney transplantation. In the case of persistent or recurrent SHPT after the initial PTx, localization of the causative PTGs with autotransplantation is challenging as causative PTGs can exist in the neck, mediastinum, or autotransplanted areas. Additionally, the efficacy and cost-effectiveness of calcimimetics and PTx are increasingly being discussed. In this review, medical and surgical treatments for SHPT are described.

Possible Advantage of Glucagon-Like Peptide 1 Receptor Agonists for Kidney Transplant Recipients With Type 2 Diabetes.

CONTEXT: Glucagon-like peptide-1 (GLP-1) receptor agonists (RAs) have the potential to improve native kidney function. OBJECTIVE: This work aimed to elucidate the possible protective effects of GLP-1 RAs on kidney graft function after successful kidney transplantation (KTX). METHODS: This retrospective cohort study included all KTX recipients (KTRs) at our facility with type 2 diabetes who were followed up from 1 month post-transplantation for 24 months or longer as of December 31, 2020. We investigated associations between the use of GLP-1 RAs and other antidiabetic medications (non-GLP-1 RAs) and the risk of sustained estimated glomerular filtration rate (eGFR) reduction (40% reduction compared with baseline for 4 months) for KTRs with type 2 diabetes. We calculated the propensity score of initiating GLP-1 RAs compared with that of initiating non-GLP-1 RAs as a function of baseline covariates using logistic regression. The inverse probability of the treatment-weighted odds ratio was estimated to control for baseline confounding variables. Sodium-glucose cotransporter 2 inhibitor use was a competing event. The primary outcome was sustained eGFR reduction of at least 40% from baseline for 4 months post-transplantation. RESULTS: Seventy-three patients were GLP-1 RA users and 73 were non-GLP-1 RA users. Six patients and 1 patient in the non-GLP-1 RA and GLP-1 RA groups had sustained eGFR reduction. GLP-1 RA use after KTX was associated with a lower risk of sustained eGFR reduction. CONCLUSION: GLP-1 RAs resulted in lower eGFR reduction compared with non-GLP-1 RAs and may contribute to better kidney graft survival after KTX.