Prevalence and risk factors for tertiary hyperparathyroidism in kidney transplant recipients

SPECT/CT in addition to subtraction parathyroid scintigraphy in hyperparathyroidism: diagnostic performance in a cohort of predominantly end-stage renal disease patients

BACKGROUND

SPECT/CT has been well established as a valuable technique in nuclear medicine parathyroid imaging, but most previous studies were done in patients with primary hyperparathyroidism. In this retrospective study, we examined the diagnostic performance of [99mTc]NaTcO4 / [99mTc]Tc-MIBI planar subtraction parathyroid scintigraphy (PS), SPECT/CT, and a combination of the two in a patient cohort consisting of mostly end-stage renal disease (ESRD) patients with secondary or tertiary hyperparathyroidism, using histopathological results as the reference standard.

RESULTS

Among 116 patients included, 98 (84.5%) had ESRD. The overall sensitivity of subtraction PS, SPECT/CT and combined interpretation was 69% (95% confidence interval: 64-73%), 67% (61-72%), and 79% (74-84%), while the specificity was 68% (59-76%), 71% (61-80%), and 60% (50-70%), respectively. For patients without ESRD with predominantly primary hyperparathyroidism, the sensitivity was 93% (70-99%), 89% (57-98%), and 100% (70-100%), and the specificity was 88% (76-94%), 87% (71-95%), and 84% (67-93%), respectively. For those with ESRD with predominantly tertiary and secondary hyperparathyroidism, the sensitivity was 67% (62-72%), 66% (60-71%), 78% (73-83%), and the specificity was 55% (42-67%), 57% (43-70%), and 43% (30-58%), respectively.

CONCLUSION

SPECT/CT was not superior to subtraction PS in ESRD patients with hyperparathyroidism. Combining these two techniques improves sensitivity, but likely with the expense of reduction in specificity. Both planar subtraction PS and SPECT/CT have suboptimal diagnostic performance in ESRD patients compared with non-ESRD patients where these techniques provide impressive sensitivity and specificity.

Surgical outcomes of parathyroidectomy for pre-kidney transplantation versus post-kidney transplantation patients

BACKGROUND

Hyperparathyroidism (HPT) is common in end-stage kidney disease and resolves in less than half of kidney transplant (KT) recipients. The ideal timing of parathyroidectomy (PTX), before or after KT, remains unclear. We sought to understand differences in morbidity and mortality after PTX pre-KT and post-KT.

METHODS

We identified adult patients who underwent PTX pre-KT or post-KT between 2012 and 2021 utilizing the National Surgical Quality Improvement Program database. Demographics, clinical characteristics, morbidity, and mortality were compared. Adjusted logistic regression with propensity score weighting assessed odds of 30-day composite morbidity, major adverse cardiovascular events (MACE), readmission, and mortality.

RESULTS

We identified 1972 patients who underwent PTX pre-KT and 541 patients who underwent PTX post-KT. Post-KT HPT patients were older (mean age 53.9 v 48.2 and p < 0.01) and more commonly White (45.3% v 32.3% and p < 0.01) and diabetic (30.0% v 18.5% and p < 0.01). In comparison, pre-KT HPT patients were more commonly Black (53.2% v 30.1%), had American Society of Anesthesiologists (ASA) class 3-4 (98.0% v 89.6% and p < 0.01), chronic obstructive pulmonary disease (4.2% v 1.5% and p < 0.01), and congestive heart failure (4.4% v 1.1% and p < 0.01). After adjusting for confounders, patients pre-KT had 1.72-fold increased odds of morbidity (95% confidence interval [CI]: 1.13-2.61), 8.39-fold increased odds of MACE (95% CI: 1.13-62.18), and 2.07-fold increased odds of readmission (95% CI: 1.38-3.10). There was no difference in mortality or risk of infections.

CONCLUSIONS

Patients who underwent PTX prior to KT were at significantly increased risk for 30-day morbidity and MACE, but no different odds of mortality compared to PTX after KT. This can help inform decision-making regarding timing of PTX in patients with HPT.

Calcimimetics or parathyroidectomy for kidney transplant recipients: is there still a question? a systematic review, meta-analysis and trial sequential analysis

PURPOSE

Secondary hyperparathyroidism is one of the most common complications of chronic kidney disease. The optimal treatment for chronic kidney disease nowadays is kidney transplant. Nonetheless, hyperparathyroidism does not always resolve after transplantation leading to tertiary hyperparathyroidism. The management of tertiary hyperparathyroidism can be either medical (calcimimetics) or surgical (parathyroidectomy). The aim of this study is to compare the medical and surgical treatment in terms of control of hyperparathyroidism and long-term implications on kidney graft function.

METHODS

We carried out a systematic review and meta-analysis of relevant studies up to March 2024 on MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials and Scopus databases. We compared the parathyroid hormone, calcium, creatinine and estimated glomerular filtration rate between the groups of patients that were treated with parathyroidectomy and those that were treated with calcimimetcs. Subsequently, we performed a trial sequential analysis to corroborate our findings.

RESULTS

Four studies were included in the final analysis with a total number of 247 patients. Parathyroidectomy resulted in a greater decrease in parathyroid hormone and calcium levels (WMD 149.37, CI 95% 126.81-171.93, p < 0.0001 and WMD 0.7, CI 95% 0.45-0.96, p < 0.0001 respectively) but there was no difference between the surgical and medical management groups in the creatinine and eGFR levels (CI 95%, -0.62-0.17, p = 0.27 and CI 95%, -8.06 - 20.54 p = 0.39). The trial sequential analysis corroborated these findings.

CONCLUSION

Parathyroidectomy is more effective in controlling hyperparathyroidism in kidney transplant recipients, as it leads to a greater decrease in parathyroid hormone and calcium levels. However, there is no difference in the long-term function of the kidney graft, as the creatinine and estimated glomerular filtration values were similar in the surgical and medical management groups.

Subtotal Versus Total Parathyroidectomy for the Management of Tertiary Hyperparathyroidism: A Systematic Literature Review and Meta-Analysis of Optimal Surgical Modality

Background: Surgery is the definitive treatment option for tertiary hyperparathyroidism (THPT), however, the optimal surgical approach remains unclear. We aimed to compare total parathyroidectomy (PTX) with auto-transplantation vs subtotal PTX for THPT through a systematic review and meta-analysis.Methods: PubMed, Embase, and Web of Science were searched for studies comparing outcomes of total vs subtotal PTX for THPT. A total of 28 studies (n = 1000 patients) met the inclusion criteria.Results: The mean age was 46.5 years and 53% were female. The proportion of females (59% vs 49%) was higher in the total PTX with auto-transplantation cohort (P = .008). Both procedures had similar preoperative calcium and PTH levels. Postoperative and 6-month calcium and PTH were also comparable between groups, except transiently higher post-operative PTH in the total PTX with auto-transplantation cohort (P = .03). Hypercalcemia cure rates were 98%-100% with no difference between surgical techniques (P = .67). Safety profiles were comparable and low.Conclusions: Total PTX with auto-transplantation and subtotal PTX yield similar efficacy and safety for THPT, with no significant differences in cure rates, recurrence, complications, or biochemical control.

Calcium phosphate deposition, tertiary hyperparathyroidism, and the long-term effect on kidney allografts

BACKGROUND

Tertiary hyperparathyroidism adversely affects kidney allografts, with calcium phosphate deposition hypothesized to be an underlying cause. We analyzed allograft biopsies to investigate risk factors for calcium phosphate deposition and understand its impact on allograft function.

METHODS

We reviewed patients who underwent kidney transplantation from 2017 to 2019. Tertiary hyperparathyroidism was defined as an elevated parathyroid hormone and hypercalcemia beyond 3 months' posttransplant or being prescribed cinacalcet. Allograft failure was defined as needing dialysis posttransplantation or retransplantation beyond 3 months' posttransplant. Three- and 12-month allograft biopsies were reviewed for calcium phosphate deposition. The χ2, t-test, and multivariate regression were used for statistical analysis.

RESULTS

Of 159 patients who underwent kidney transplantation, 59 (37.1%) were diagnosed with tertiary hyperparathyroidism. Longer preoperative dialysis vintage (odds ratio, 1.47; confidence interval, 1.22-1.80 P < .001) and preoperative cinacalcet usage (odds ratio, 18.4; confidence interval, 7.24-53.0 P < .001) were associated with tertiary hyperparathyroidism. In total, 36 of 59 (61%) patients with tertiary hyperparathyroidism had calcium phosphate deposition on 3- or 12-month kidney allograft biopsy compared with 23 of 100 (23%) patients without tertiary hyperparathyroidism (P < .001). Tertiary hyperparathyroidism (odds ratio, 6.01; confidence interval, 2.91-13.0 P < .001) was associated with calcium phosphate deposition. Calcium phosphate deposition and tertiary hyperparathyroidism were not associated with worse glomerular filtration rate at 3 years' posttransplantation. Of those with data available at 3 years' posttransplantation, 21 of 49 (42.9%) patients remained on cinacalcet. There were 3 of 159 (2%) patients who had allograft failure, 2 of whom had both tertiary hyperparathyroidism and calcium phosphate deposition.

CONCLUSION

Preoperative variables associated with tertiary hyperparathyroidism included longer dialysis vintage and cinacalcet use. Tertiary hyperparathyroidism was the main risk factor for calcium phosphate deposition posttransplantation. In our population, calcium phosphate deposition and tertiary hyperparathyroidism were not significantly associated with lower glomerular filtration rate.

Association between atopic dermatitis with hyperparathyroidism not mediated by vitamin D in the United States (NHANES 2005-2006)

The association between atopic eczema and hyperparathyroidism remains doubtful. Participants with atopic dermatitis have lower serum vitamin D levels. Whether it is mediated by vitamin D or other potential factors remains uncertain as well. This study aims to determine the impact of AD on hyperparathyroidism and the direct mediators. A total of 7266 subjects in the National Health and Nutrition Examination Survey (NHANES) from 2005 to 2006 were included in this study. Diagnoses of AD were based on questionnaire answering. Hyperparathyroidism was assessed by biochemical examination. Weighted logistic regression analysis reported odds ratios (ORs), and mediation analysis was applied to evaluate the mediating effect. Subgroup analysis stratified by age and vitamin D level was further performed after the confirmation of the association. Participants with AD had higher odds of developing hyperparathyroidism (OR [95% CI], 1.86 [1.040, 3.326], P = 0.041). The association was not mediated by vitamin D or other potential factors, including calcium, phosphorus, BMI and CRP. Otherwise, subgroup analysis demonstrated that the association exhibited variations based on age and vitamin D level, especially in subjects older than 60 years old and with normal vitamin D levels. Participants with AD are inclined to have hyperparathyroidism. We recommend a more rigorous focus on hyperparathyroidism in patients with AD, especially those over 60 years of age and with normal serum vitamin D levels.

Timing of parathyroidectomy for tertiary hyperparathyroidism after kidney transplant

BACKGROUND

Parathyroidectomy has been shown to be superior to medical management in treating hypercalcemia and preserving renal allograft function in patients with tertiary hyperparathyroidism after kidney transplant. Despite this evidence, parathyroidectomy remains underused. We aimed to evaluate outcomes in patients with tertiary hyperparathyroidism after kidney transplant based on management strategy (cinacalcet or parathyroidectomy) and optimal timing of parathyroidectomy.

METHODS

Data from TriNetX Dataworks included adult kidney transplant patients diagnosed with tertiary hyperparathyroidism between 1998 and 2021. Patients who underwent parathyroidectomy were compared with those receiving cinacalcet. Subgroups based on parathyroidectomy timing after transplant were analyzed (within 6 months, 6 months to 1 year, and between 1 and 3 years). Descriptive statistics and relative risks were calculated using TriNetX Live.

RESULTS

Patients receiving cinacalcet (n = 162) had a 77% higher risk of persistent hypercalcemia and a 73% higher risk of elevated parathyroid hormone levels than those who underwent parathyroidectomy (n = 338) within 3-10 years after the index event (start of cinacalcet or surgery). Parathyroidectomy performed 1 year after transplant (n = 132) was associated with a 57% lower risk of kidney stone formation and patients were 2 times more likely to maintain normal glomerular filtration rate than parathyroidectomy performed 1-3 years after transplant (n = 57). Even earlier parathyroidectomy (within 6 months of kidney transplant, n = 55) showed a 62% lower risk of persistent hypercalcemia, hyperphosphatemia, and kidney stone formation than surgery between 6 months and 1 year after transplant (n = 77).

CONCLUSION

Parathyroidectomy is more effective than cinacalcet in managing tertiary hyperparathyroidism after kidney transplant. In addition, opting for early parathyroidectomy (within 6 months after transplant) could enhance long-term outcomes.

Association Between Pre-Kidney Transplantation Elevated Parathyroid Hormone and Posttransplantation Graft Loss

BACKGROUND

Before kidney transplantation (KT), most patients have an elevated parathyroid hormone (PTH). However, the impact of PTH on post-KT mortality and graft loss is unclear. We quantified the association between PTH levels measured at transplantation and adverse post-KT outcomes.

STUDY DESIGN

We leveraged a prospective longitudinal cohort of 1,136 KT recipients from a single tertiary care center between December 2008 and February 2020. Pre-KT PTH levels were abstracted retrospectively. Adjusted multivariable Cox proportional hazards models were used to estimate the association between pre-KT PTH levels and mortality and death-censored graft loss (DCGL).

RESULTS

Of 1,136 recipients, pre-KT PTH levels were 300 pg/mL or less in 62.3% and more than 600 pg/mL in 12.5%. Compared with those with a pre-KT PTH 300 pg/mL or less, patients with a pre-KT PTH more than 600 pg/mL were more likely to be Black (51.4% vs 34.6%) and have a longer dialysis vintage (4.8 vs 1.7 years, p < 0.001). Those with a pre-KT PTH more than 600 pg/mL had a higher 10-year cumulative incidence of DCGL than those with PTH 300 pg/mL or less (31.7% vs 15.4%, p < 0.001). After adjusting for confounders, pre-KT PTH more than 600 pg/mL was associated with a 1.76-fold increased risk of DCGL (95% CI 1.16 to 2.65). The magnitude of this association differed by race (p interaction = 0.011) and by treatment (p interaction = 0.018). Among non-Black patients, a PTH more than 600 pg/mL was associated with a 3.21-fold increased risk of DCGL compared with those with PTH 300 pg/mL or less (95% CI 1.77 to 5.81). Among untreated patients, those with PTH more than 600 pg/mL had a 2.54-fold increase in DCGL (95% CI 1.44 to 4.47). No association between pre-KT PTH and mortality risk was observed.

CONCLUSIONS

PTH more than 600 pg/mL before KT increased the risk of DCGL by 76%, demonstrating the importance of treating PTH before KT to prevent graft loss in a contemporary era with the introduction and widespread availability of medical therapy.

Back to my future: life after surgery for tertiary hyperparathyroidism

PURPOSES

Evaluate the changes in quality of life (QoL) in patients affected by tertiary hyperparathyroidism (THPT) after surgical treatment using the Parathyroidectomy Assessment of Symptoms (PAS) and Short Form-36 (SF-36) questionnaires.

METHODS

Single centre longitudinal retrospective, single-institution analysis of 34 patients with THPT and submitted to parathyroidectomy between 2015 and 2021. The PAS and SF-36 questionnaires were administered before surgery and 24 months after discharge.

RESULTS

A significative QoL amelioration was registered in physical SF-36 (42.4 ± 11.7 vs 56.7 ± 9.2; P < 0.001), mental SF-36 (47.3 ± 12.1 vs 61.8 ± 7.9; P < 0.001) and PAS score (582 ± 163 vs 293 ± 141; P < 0.001) with a significative improvement of all the 13 symptoms considered. We found that pre-operative intact parathormone (iPTH) levels, preoperative T-score and time of haemodialysis before RTX were predictors of both PAS and SF-36 mental score modifications. A positive correlation was also fund between pre-operative PAS values and their post operative cutback.

CONCLUSIONS

Parathyroidectomy for THPT brings to a concrete amelioration of all the disease-related and nonspecific symptoms with significative improvement of QoL. To develop a tailored approach of every patient's needs, from diagnosis to future treatment, we suggest to introduce the symptoms assessment scale as standard stage in periodic evaluations.

A novel nomogram for predicting the risk of persistent hyperparathyroidism after kidney transplantation

PURPOSE

Persistent hyperparathyroidism (PTHPT) in kidney transplant recipients is associated with bone loss, graft dysfunction and cardiovascular mortality. There is no clear consensus on the management of PTHPT. Accurate risk prediction of the disease is needed to support individualized treatment decisions. We aim to develop a useful predictive model to provide early intervention for hyperparathyroidism in these patients.

METHODS

We retrospectively analyzed 263 kidney transplantations in the urology department of China-Japan Friendship Hospital from January 2018 to December 2022. The overall cohort was randomly assigned 70% of the patients to the training cohort and 30% to the validation cohort. Univariate and multivariate logistic regression analyses were used to identify independent risk factors for PTHPT and to construct the predictive model. This model was assessed regarding discrimination, consistency, and clinical benefit.

RESULTS

The occurrence of PTHPT was 25.9% (68 out of 263 patients) in this study. Dialysis duration, postoperative 3-month intact parathyroid hormone (iPTH), 3-month corrected calcium (cCa), and 3-month phosphorus (P) are independent risk factors for the development of PTHPT. The nomogram showed good discrimination with the area under the curve (AUC) value of 0.926 in the training cohort and 0.903 in the validation cohort. The calibration curve and decision curve also showed that the model was well-evaluated.

CONCLUSION

We developed a validated nomogram model to predict PTHPT after kidney transplantation. This can help the clinic prevent and control PTHPT early and improve patients' prognosis.

Long-term effects of hypercalcemia in kidney transplant recipients with persistent hyperparathyroidism

BACKGROUND

Hypercalcemia is highly prevalent in kidney transplant recipients with hyperparathyroidism. However, its long-term impact on graft function is uncertain.

METHODS

We conducted a prospective cohort study investigating adverse graft outcomes associated with persistent hypercalcemia (free calcium > 5.2 mg/dL in ≥ 80% of measures) and inappropriately elevated intact parathyroid hormone (> 30 pg/mL) in kidney transplant recipients. Asymptomatic mild hypercalcemia was monitored unless complications developed.

RESULTS

We included 385 kidney transplant recipients. During a 4-year (range 1-9) median follow-up time, 62% of kidney transplant recipients presented persistent hypercalcemia. Compared to kidney transplant recipients without hypercalcemia, there were no significant differences in graft dysfunction (10% vs. 12%, p = 0.61), symptomatic urolithiasis (5% vs. 3%, p = 0.43), biopsy-proven calcium deposits (6% vs. 5%, p = 1.0), fractures (6% vs. 4%, p = 0.64), and a composite outcome of urolithiasis, calcium deposits, fractures, and parathyroidectomy indication (16% vs. 13%, p = 0.55). In a subset of 76 kidney transplant recipients, subjects with persistent hypercalcemia had higher urinary calcium (median 84 [43-170] vs. 38 [24-64] mg/day, p = 0.03) and intact fibroblast growth factor 23 (median 36 [24-54] vs. 27 [19-40] pg/mL, p = 0.04), and lower 25-hydroxyvitamin D levels (11.3 ± 1.2 vs. 16.3 ± 1.4 ng/mL, p < 0.001). In multivariate analysis, pretransplant intact parathyroid hormone < 300 pg/mL was associated with a reduced risk of post-transplant hypercalcemia (OR 0.51, 95% CI 0.32-0.80).

CONCLUSIONS

Long-term persistent mild hypercalcemia (tertiary hyperparathyroidism) was frequent in kidney transplant recipients in our series. This condition presented with lower phosphate and 25-hydroxyvitamin D, and higher urinary calcium and intact fibroblast growth factor 23 levels compared to kidney transplant recipients without hypercalcemia, resembling a mild form of primary hyperparathyroidism. Despite these metabolic derangements, the risk of adverse graft outcomes was low.

Estimating the global prevalence of secondary hyperparathyroidism in patients with chronic kidney disease

Background

Chronic kidney disease (CKD)-related secondary hyperparathyroidism (SHPT) is associated with higher morbidity and death. The goal of this study was to mine the SHPT data already available to do a meta-analysis on the global prevalence of SHPT caused by CKD.

Methods

Embase, Medline, Web of Science, Cochrane Central Databases, and Google Scholar were searched to identify studies on the prevalence of SHPT due to CKD from inception to November 2023. Pooled prevalence was calculated using the DerSimonian-Laird random effects model with a logit transformation.

Results

Twenty-one eligible studies involving 110977 patients were included. Our results revealed that the estimated global prevalence of SHPT due to CKD was 49.5% (95% CI 30.20-68.18), regardless of the diagnostic criteria. For subgroup analysis, Southern Asia (84.36%, 95% CI 79.35-88.34) had a significantly higher SHPT prevalence than other geographic regions. SHPT due to CKD was most prevalent in China (85.14%, 95% CI 81.74-88.00).

Conclusions

SHPT due to CKD is highly prevalent. This necessitates awareness and therapeutic approaches from primary care physicians, medical professionals, and health strategy authorities.

Systematic Review Registration

https://www.crd.york.ac.uk/PROSPERO, identifier CRD42024514007.

Coincidence or Causality: Parathyroid Carcinoma in Chronic Kidney Disease-Case Report and Literature Review

Parathyroid carcinoma (PC) associated with primary hyperparathyroidism (PHPT) has been well investigated in recent years. Data regarding PC evolution in secondary hyperparathyroidism (SHPT) due to chronic kidney disease (CKD) are, however, scarce. Most features that raise the suspicion of PC in PHPT are part of the usual SHPT evolution in CKD, mirroring the natural changes undergone by the parathyroid glands. Therefore, pre-surgically establishing the malignant or benign character of the lesions is cumbersome. We present two cases of PC in end-stage renal disease, one of which was bilateral, diagnosed after total parathyroidectomy in a high-volume parathyroid surgery center. A literature review of the data was also performed. A systematic search of the PubMed/MEDLINE database until January 2024 identified 42 cases of PC associated with SHPT. Understanding the PC features in CKD might improve associated bone and mineral disease management, and reduce the risk of metastasis, parathyromatosis, or recurrence. Irradiation, prolonged immunosuppression, long dialysis vintage, and genotype may predispose to the malignant transformation of chronically stimulated parathyroids. Despite postsurgical diagnosis, favorable outcomes occurred when distant metastases were absent, even without "en bloc" resection. Further research is warranted to delineate specific diagnostic and therapeutic approaches tailored to this particular patient subpopulation.

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.

Ultrasound-Guided Radiofrequency Ablation in Tertiary Hyperparathyroidism: A Prospective Study

OBJECTIVE

To prospectively evaluate the outcomes of ultrasound (US)-guided radiofrequency ablation (RFA) in tertiary hyperparathyroidism (THPT).

MATERIALS AND METHODS

Patients with THPT underwent RFA between September 2017 and January 2022. Laboratory parameters, including serum intact parathyroid hormone (iPTH) levels, were monitored for 48 months after RFA and compared with the levels at baseline. Complications related to RFA and changes in hyperparathyroidism-related clinical symptoms were recorded before and after RFA.

RESULTS

A total of 42 patients with THPT were recruited for this study. Ultimately, 36 patients with renal failure and 2 patients who underwent successful renal transplantation (male:female, 17:21; median age, 54.5 years) were enrolled. The follow-up time was 21.5 ± 19.0 months in the 36 patients with renal failure. In these 36 patients, iPTH levels were significantly decreased to 261.1 pg/mL at 48 months compared with the baseline value of 1284.9 pg/mL (P = 0.012). Persistent hyperparathyroidism, defined as iPTH levels maintained at > 585.0 pg/mL for 6 months after treatment, occurred in 4.0% of patients (1/25). Recurrent hyperparathyroidism, defined as iPTH levels > 585.0 pg/mL after 6 months, were 4.0% (1/25) and 0.0% (0/9) at 6 months and 4 years after treatment, respectively. In two patients with THPT after successful renal transplantation, iPTH decreased from the baseline value of 242.5 and 115.9 pg/mL to 171.0 and 62.0 pg/mL at 6 months after treatment. All complications resolved within 6 months of ablation without medical intervention, except in 10.5% (4/38) patients with permanent hypocalcemia. The overall symptom recovery rate was 58.8% (10/17). The severity scores for bone pain, arthralgia, and itchy skin associated with hyperparathyroidism improved after treatment (P < 0.05).

CONCLUSION

US-guided RFA is an effective and safe alternative to surgery in the treatment of patients with TPTH and improves hyperparathyroidism-related clinical symptoms.

Corrigendum: Impact of hyperparathyroidism and its different subtypes on long term graft outcome: a single Transplant Center cohort study

[This corrects the article DOI: 10.3389/fmed.2023.1221086.].

Surgical treatment of tertiary hyperparathyroidism: does one fit for all?

BACKGROUND

Tertiary hyperparathyroidism (3HPT) is defined as a condition of excessive autonomous excretion of intact parathyroid hormone (iPTH) with persistent hypercalcemia (>10.5 mg/dL) that lasts for more than 12 months after a successful kidney transplantation, in the context of a long course secondary hyperparathyroidism (2HPT). The chronic high levels of iPTH cause a worsening of graft function, accompanied by systemic symptoms of hypercalcemia. The only curative therapy is parathyroidectomy (PTX). It remains unclear whether total parathyroidectomy with autotransplantation (TPTX-AT) or subtotal parathyroidectomy (SPTX) lead to better outcomes.

AIMS

The aim of this retrospective, single-institution cohort study is to evaluate the rate of persistent or recurrent disease and postoperative calcium/iPTH disturbances in patients treated with TPTX-AT or SPTX for 3HPT.

METHODS

A single-center retrospective analysis of 3HPT patients submitted to TPTX-AT or SPTX between 2007-2020 with at least 24 months follow-up was conducted. The outcome parameters included persistence/recurrence of disease, incidence of transitory hypocalcemia, and temporary/permanent hypoparathyroidism.

RESULTS

A cohort of 52 patients was analyzed and divided in two groups: 38 (73%) were submitted for TPTX-AT, and 14 patients (27%) were submitted for SPTX. The TPTX-AT population showed lower plasmatic calcium concentrations compared with the SPTX group during the entire follow-up period (p<0.001). There were eight cases (21%) of transitory hypocalcemia in the TPTX-AT group and none in the SPTX group, with p=0.065. Two cases (5%) of temporary hypoparathyroidism occurred in the TPTX-AT group and none in the SPTX group, with p= 0.530. There were no cases of permanent hypoparathyroidism and no cases of persistent disease. No statistical difference was assessed for the recurrence of 3HPT between the TPTX-AT group and the SPTX group (N=1, 3% vs N=1, 7%) (p=0.470).

CONCLUSION

No significative difference was registered between the TPTX-AT and SPTX groups in terms of persistence/recurrence of disease, incidence of transitory hypocalcemia, and temporary/permanent hypoparathyroidism. Mean calcium levels iPTH values were statistically lower among the TPTX-AT group compared with the SPTX group while remaining always in the range of normality.

Does race impact outcomes after parathyroidectomy for secondary and tertiary hyperparathyroidism?

BACKGROUND

Racial disparities in care exist for diseases with heterogeneous treatment guidelines. The impact of these disparities on outcomes after parathyroidectomy for secondary(2HPT) and tertiary hyperparathyroidism(3HPT) was explored.

METHODS

The 2015-2019 NSQIP datasets were used. Patients who underwent parathyroidectomy for 2HPT and 3HPT were identified and analyzed separately. Patients were stratified by race (white vs. non-white); demographics, comorbidities, and outcomes were compared. Studied outcomes included 30-day morbidity, mortality, unplanned reoperation, readmission, and postoperative length of stay(LOS).

RESULTS

There were 1,150 patients with 2HPT and 262 with 3HPT. For 2HPT, 65.5% were non-white; morbidity, reoperation, and prolonged LOS(>3days) occurred disproportionately more often in non-white patients. Non-white race was independently associated with morbidity; higher ASA class and alkaline phosphatase levels were associated with prolonged LOS. For 3HPT, 53.1% were non-white; a prolonged LOS(>1day) occurred disproportionately more often in non-white patients. Higher alkaline phosphatase levels were independently associated with prolonged LOS.

CONCLUSION

Race and markers of advanced disease negatively impact outcomes after parathyroidectomy for 2HPT and 3HPT. Attention to racial disparities and earlier referral may positively impact outcomes.

Treatment of Secondary Hyperparathyroidism and Posttransplant Tertiary Hyperparathyroidism

INTRODUCTION

Secondary hyperparathyroidism (sHPT) is prevalent in dialysis patients and can lead to tertiary hyperparathyroidism (tHPT) after kidney transplantation. We aimed to assess the association of pretransplant sHPT treatment on posttransplant outcomes.

METHODS

We reviewed kidney transplant patients treated with parathyroidectomy or cinacalcet for sHPT. We compared patients biochemical and clinical parameters, and outcomes based on sHPT treatment.

RESULTS

A total of 41 patients were included: 18 patients underwent parathyroidectomy and 23 patients received cinacalcet prior to transplantation. There were no significant differences between demographics, comorbidities, allograft characteristics or pre-sHPT intervention parathyroid hormone (PTH) and calcium levels. Patients that underwent parathyroidectomy were on dialysis for longer, although not significantly (71.9 versus 42.3 mo, P = 0.051). At time of transplantation, patients treated by parathyroidectomy had increased rates of controlled sHPT (88.9%; 16/18 versus 47.8%; 11/23, P = 0.008). Patients treated by parathyroidectomy had decreased development of tHPT (5.9%; 1/17; versus 42.1%; 8/19, P = 0.020) as well as decreased rates of posttransplant treatment with cinacalcet (11.1%; 2/18 versus 52.2%; 12/23, P = 0.008). Three patients treated with cinacalcet underwent parathyroidectomy after transplantation. Median PTH after transplant remained lower in patients treated by parathyroidectomy prior to transplant compared to those treated with cinacalcet (60.7 [interquartile range 39.7-133.4] versus 170.0 [interquartile range 128.4-292.7], P = 0.001). Allograft function and survival were similar for parathyroidectomy and cinacalcet, with median follow-up after transplantation of 56.7 and 34.2 mo, respectively.

CONCLUSIONS

sHPT treated by parathyroidectomy is associated with controlled PTH levels at transplantation and decreased rates of tHPT. Long-term outcomes should be studied on a larger scale.

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.

Resolution of Secondary Hyperparathyroidism After Kidney Transplantation and the Effect on Graft Survival

OBJECTIVE

Hyperparathyroidism (HPT) is nearly universal in patients with end-stage kidney disease. Kidney transplantation (KT) reverses HPT in many patients, but most studies have only focused on following calcium and not parathyroid hormone (PTH) levels. We sought to study the prevalence of persistent HPT post-KT at our center and its effect on graft survival.

METHODS

Patients who underwent KT from January 2015 to August 2021 were included and characterized by post-KT HPT status at the most recent follow-up: resolved (achieving normal PTH post-KT) versus persistent HPT. Those with persistent HPT were further stratified by the occurrence of hypercalcemia (normocalcemic versus hypercalcemic HPT). Patient demographics, donor kidney quality, PTH and calcium levels, and allograft function were compared between groups. Multivariable logistic regression and Cox regression with propensity score matching were conducted.

RESULTS

Of 1554 patients, only 390 (25.1%) patients had resolution of renal HPT post-KT with a mean (±SD) follow-up length of 40±23 months. The median (IQR) length of HPT resolution was 5 (0-16) months. Of the remaining 1164 patients with persistent HPT post-KT, 806 (69.2%) patients had high PTH and normal calcium levels, while 358 (30.8%) patients had high calcium and high PTH levels. Patients with persistent HPT had higher parathyroid hormone (PTH) at the time of KT [403 (243-659) versus 277 (163-454) pg/mL, P <0.001] and were more likely to have received cinacalcet treatment before KT (34.9% vs. 12.3%, P <0.001). Only 6.3% of patients with persistent HPT received parathyroidectomy. Multivariable logistic regression showed race, cinacalcet use pre-KT, dialysis before KT, receiving an organ from a deceased donor, high PTH, and calcium levels at KT were associated with persistent HPT post-KT. After adjusting for patient demographics and donor kidney quality by propensity score matching, persistent HPT (HR 2.5, 95% CI 1.1-5.7, P =0.033) was associated with a higher risk of allograft failure. Sub-analysis showed that both hypercalcemic HPT (HR 2.6, 95% CI 1.1-6.5, P =0.045) and normocalcemic HPT (HR 2.5, 95% CI 1.3-5.5, P =0.021) were associated with increased risk of allograft failure when compared with patients with resolved HPT.

CONCLUSION

Persistent HPT is common (75%) after KT and is associated with a higher risk of allograft failure. PTH levels should be closely monitored after kidney transplantation so that patients with persistent HPT can be treated appropriately.

Impact of hyperparathyroidism and its different subtypes on long term graft outcome: a single Transplant Center cohort study

PURPOSE

We studied the association between parathormone (PTH) levels and long-term graft loss in RTx patients (RTx-p).

METHODS

We retrospectively evaluated 871 RTx-p, transplanted in our unit from Jan-2004 to Dec-2020 assessing renal function and mineral metabolism parameters at 1, 6, and 12 months after RTx. Graft loss and death with functioning graft during follow-up (FU, 8.3[5.4-11.4] years) were checked.

RESULTS

At month-1, 79% had HPT, of which 63% with secondary HPT (SHPT) and 16% tertiary HPT (THPT); at month-6, HPT prevalence was 80% of which SHPT 64% and THPT 16%; at month-12 HPT prevalence was 77% of which SHPT 62% and THPT 15%. A strong significant correlation was found between HPT type, PTH levels and graft loss at every time point. Mean PTH exposure remained strongly and independently associated to long term graft loss (OR 3.1 [1.4-7.1], p = 0.008). THPT was independently associated with graft loss at month-1 when compared to HPT absence and at every time point when compared to SHPT. No correlation was found with RTx-p death. Discriminatory analyses identified the best mean PTH cut-off to predict long-term graft loss to be between 88.6 and 89.9 pg/mL (AUC = 0.658). Cox regression analyses highlighted that THPT was strongly associated with shorter long-term graft survival at every time-point considered.

CONCLUSION

High PTH levels during 1st year of RTx seem to be associated with long term graft loss.

Secondary Hyperparathyroidism and Cognitive Decline

Purpose of Review

Secondary hyperparathyroidism (SHPT) likely contributes to the high prevalence of cognitive decline found among individuals with end-stage kidney disease (ESKD). Our objective is to critically evaluate the recent literature regarding the association between SHPT and cognitive decline and identify potential mechanisms.

Recent Findings

Nine studies assessing the relationship between SHPT and cognition have been published in the last two decades, each showing that elevated parathyroid hormone (PTH) levels were associated with cognitive decline. One also found structural changes within the brain related to SHPT. Additionally, two found that SHPT treatment decreases the risk of cognitive decline in ESKD patients.

Summary

SHPT is associated with cognitive impairment. However, the severity of SHPT associated with these changes and the specific cognitive domains affected remain unclear. Future studies are needed to focus on specific cognitive domains, the trajectory of cognitive decline, and optimal treatment strategies including the impact of kidney transplant and tertiary hyperparathyroidism.

Factors Associated With Persistent Post-transplant Hyperparathyroidism After Index Renal Transplantation

INTRODUCTION

Secondary hyperparathyroidism (SHP) is common in end-stage renal disease and may progress to persistent post-transplant hyperparathyroidism (PTHP) following renal transplantation (RT). We sought to describe the frequency and determine factors associated with the incidence of PTHP for patients undergoing RT at a single institution that restricts RT for patients with uncontrolled SHP with a parathyroid hormone (PTH) of >800pg/mL at time of initial transplant evaluation.

METHODS

We conducted a single-institution retrospective study of adults undergoing index RT from 2012 to 2020 who had a calcium and PTH level within 12 mo prior to RT and at least 6 mo following RT. PTHP was defined as calcium of >10 mg/dL with an elevated PTH > 88pg/mL at six or more months following RT. Univariate analysis and multivariable logistic regression were performed for factors associated with developing PTHP.

RESULTS

We identified 1110 patients with RT, 65 were excluded for prior RT, 549 did not have a pre-RT and post-RT calcium, and PTH laboratories for inclusion, yielding 496 for analysis. Following RT, 39 patients (7.9%) developed PTHP, compared to those who did not develop PTHP; these patients had significantly higher pre-RT PTH, pre-RT calcium, and frequency of calcimimetic therapy. In multivariable logistic regression factors significantly associated with PTHP were pre-RT calcium of more than 10 mg/dL with an odds ratio (OR) of 3.57 (95% confidence interval [CI] 1.52-8.39, P = 0.003) and pre-RT calcimimetic therapy with an OR 1.30 (95% CI 1.06-2.85, P = 0.041). Compared with patients who had a pre-RT PTH of less than 200 pg/mL, a PTH of 200-399 pg/mL increased risk of PTHP with an OR of 4.52 (95% CI 1.95-21.5, P = 0.048) and a PTH of > 400 pg/mL increased risk of PTHP with an OR of 7.17 (95% CI 1.47-34.9, P = 0.015). In this cohort, 11 patients (28.2%) with PTHP underwent parathyroidectomy (PTx) at a mean of 1.4 y post-RT (standard deviation 0.87).

CONCLUSIONS

For patients required to have a PTH < 800pg/mL for initial transplant candidacy, the subsequent incidence of PTHP is relatively low at 7.9%. Risk factors for PTHP include higher pre-RT calcium and PTH levels and pre-RT calcimimetic therapy. PTx remains underused in the treatment of PTHP. Further study is warranted to determine the optimal PTH cutoff for transplant candidacy and recommendation for PTx in patients requiring calcimimetic therapy for SHP.

Missed Opportunities to Diagnose and Treat Tertiary Hyperparathyroidism After Transplant

INTRODUCTION

Tertiary hyperparathyroidism (3HPT) is common after renal transplant. However, guidelines for diagnosis are not clear and few patients are treated surgically. This study aims to determine rates of diagnosis and treatment of 3HPT in renal transplant patients with hypercalcemia.

MATERIALS AND METHODS

This retrospective chart review identified all renal transplant recipients at a single tertiary care institution between 2011 and 2021. Patients with post-transplant hypercalcemia (> 10.2 mg/dL) were identified. The time in months of index hypercalcemia was noted. Measurement of parathyroid hormone (PTH) levels after index hypercalcemia was determined and noted as elevated if > 64 pg/mL at least 6 mo after transplant. Documentation of symptoms of hyperparathyroidism, a diagnosis of hyperparathyroidism in the electronic medical record, and medical or surgical management of patients with classic 3HPT (elevated calcium and PTH) were determined.

RESULTS

Of 383 renal transplant recipients, hypercalcemia was identified in 132 patients. The majority of hypercalcemic patients had PTH levels measured (127, 96.2%). PTH was elevated in 109 (82.6%). Among the 109 patients with classic 3HPT, 54 (49.5%) had a documented diagnosis of hyperparathyroidism in the electronic medical record (P = 0.01). Kidney stones or abnormal DEXA scan were present in 16 (14.7%) and 18 (16.5%), respectively. Most patients were managed non-surgically (101, 92.6%); calcimimetics were prescribed for 42 (38.5%, P = 0.01). Eight (7.3%) patients with classic 3HPT were referred to a surgeon (P = 0.35); all were initially prescribed calcimimetics (P = 0.001).

CONCLUSIONS

3HPT is underdiagnosed in patients with elevated calcium and PTH levels post-transplant. A significant percentage of these patients go without surgical referral and curative treatment.

Hyperparathyroidism at 1 year after kidney transplantation is associated with graft loss

BACKGROUND

Hyperparathyroidism persists in many patients after kidney transplantation. The purpose of this study was to evaluate the association between post-transplant hyperparathyroidism and kidney transplantation outcomes.

METHODS

We identified 824 participants from a prospective longitudinal cohort of adult patients who underwent kidney transplantation at a single institution between December 2008 and February 2020. Parathyroid hormone levels before and after kidney transplantation were abstracted from medical records. Post-transplant hyperparathyroidism was defined as parathyroid hormone level ≥70 pg/mL 1 year after kidney transplantation. Cox proportional hazards models were used to estimate the adjusted hazard ratios of mortality and death-censored graft loss by post-transplant hyperparathyroidism. Models were adjusted for age, sex, race/ethnicity, college education, parathyroid hormone level before kidney transplantation, cause of kidney failure, and years on dialysis before kidney transplantation. A Wald test for interactions was used to evaluate the risk of death-censored graft loss by age, sex, and race.

RESULTS

Of 824 recipients, 60.9% had post-transplant hyperparathyroidism. Compared with non-hyperparathyroidism patients, those with post-transplant hyperparathyroidism were more likely to be Black (47.2% vs 32.6%), undergo dialysis before kidney transplantation (86.9% vs 76.6%), and have a parathyroid hormone level ≥300 pg/mL before kidney transplantation (26.8% vs 9.5%) (all P < .001). Patients with post-transplant hyperparathyroidism had a 1.6-fold higher risk of death-censored graft loss (adjusted hazard ratio = 1.60, 95% confidence interval: 1.02-2.49) compared with those without post-transplant hyperparathyroidism. This risk more than doubled in those with parathyroid hormone ≥300 pg/mL 1 year after kidney transplantation (adjusted hazard ratio = 4.19, 95% confidence interval: 1.95-9.03). The risk of death-censored graft loss did not differ by age, sex, or race (all Pinteraction > .05). There was no association between post-transplant hyperparathyroidism and mortality.

CONCLUSION

The risk of graft loss was significantly higher among patients with post-transplant hyperparathyroidism when compared with patients without post-transplant hyperparathyroidism.

Persistent hyperparathyroidism in long-term kidney transplantation: time to consider a less aggressive approach

PURPOSE OF REVIEW

Persistent hyperparathyroidism affects 50% of long-term kidney transplants with preserved allograft function. Timing, options and the optimal target for treatment remain unclear. Clinical practice guidelines recommend the same therapeutic approach as patients with chronic kidney disease.

RECENT FINDINGS

Mild to moderate elevation of parathyroid hormone (PTH) levels in long-term kidney transplants may not be associated with bone loss and fracture. Recent findings on bone biopsy revealed the lack of association between hypercalcaemic hyperparathyroidism with pathology of high bone turnover. Elevated PTH levels may be required to maintain normal bone volume. Nevertheless, several large observational studies have revealed the association between hypercalcemia and the elevation of PTH levels with unfavourable allograft and patient outcomes. Both calcimimetics and parathyroidectomy are effective in lowering serum calcium and PTH. A recent meta-analysis suggested parathyroidectomy may be performed safely after kidney transplantation without deterioration of allograft function.

SUMMARY

Treatment of persistent hyperparathyroidism is warranted in kidney transplants with hypercalcemia and markedly elevated PTH levels. A less aggressive approach should be applied to those with mild to moderate elevation. Whether treatments improve outcomes remain to be elucidated.

Timing of parathyroidectomy for kidney transplant patients with secondary hyperparathyroidism: A practical overview

Kidney transplantation remains the best treatment for patients with end-stage kidney disease, and it could partially mitigate systemic disorders of mineral and bone metabolism caused by secondary hyperparathyroidism. However, persistent hyperparathyroidism is still observed in 30-60% of patients 1 year after kidney transplantation, leading to impairment of allograft function and a disturbance of mineral metabolism. The timing of parathyroidectomy varies among transplant centers because the possible negative effects of parathyroidectomy on allograft outcomes are still unclear. This review provides a comprehensive and detailed overview of the natural course of hyperparathyroidism following kidney transplantation and the effects of the timing and extent of parathyroidectomy on allograft function. It aims to provide useful information for surgeons to propose an appropriate intervention strategy to break the vicious cycle of post-kidney transplantation hyperparathyroidism and deterioration of allograft function.

A roadmap to parathyroidectomy for kidney transplant candidates

Chronic kidney disease mineral and bone disorder may persist after successful kidney transplantation. Persistent hyperparathyroidism has been identified in up to 80% of patients throughout the first year after kidney transplantation. International guidelines lack strict recommendations about the management of persistent hyperparathyroidism. However, it is associated with adverse graft and patient outcomes, including higher fracture risk and an increased risk of all-cause mortality and allograft loss. Secondary hyperparathyroidism may be treated medically (vitamin D, phosphate binders and calcimimetics) or surgically (parathyroidectomy). Guideline recommendations suggest medical therapy first but do not clarify optimal parathyroid hormone targets or indications and timing of parathyroidectomy. There are no clear guidelines or long-term studies about the impact of hyperparathyroidism therapy. Parathyroidectomy is more effective than medical treatment, although it is associated with increased short-term risks. Ideally parathyroidectomy should be performed before kidney transplantation to prevent persistent hyperparathyroidism and improve graft outcomes. We now propose a roadmap for the management of secondary hyperparathyroidism in patients eligible for kidney transplantation that includes the indications and timing (pre- or post-kidney transplantation) of parathyroidectomy, the evaluation of parathyroid gland size and the integration of parathyroid gland size in the decision-making process by a multidisciplinary team of nephrologists, radiologists and surgeons.

The American Association of Endocrine Surgeons Guidelines for the Definitive Surgical Management of Secondary and Tertiary Renal Hyperparathyroidism

OBJECTIVE

To develop evidence-based recommendations for safe, effective, and appropriate treatment of secondary (SHPT) and tertiary (THPT) renal hyperparathyroidism.

BACKGROUND

Hyperparathyroidism is common among patients with chronic kidney disease, end-stage kidney disease, and kidney transplant. The surgical management of SHPT and THPT is nuanced and requires a multidisciplinary approach. There are currently no clinical practice guidelines that address the surgical treatment of SHPT and THPT.

METHODS

Medical literature was reviewed from January 1, 1985 to present January 1, 2021 by a panel of 10 experts in SHPT and THPT. Recommendations using the best available evidence was constructed. The American College of Physicians grading system was used to determine levels of evidence. Recommendations were discussed to consensus. The American Association of Endocrine Surgeons membership reviewed and commented on preliminary drafts of the content.

RESULTS

These clinical guidelines present the epidemiology and pathophysiology of SHPT and THPT and provide recommendations for work-up and management of SHPT and THPT for all involved clinicians. It outlines the preoperative, intraoperative, and postoperative management of SHPT and THPT, as well as related definitions, operative techniques, morbidity, and outcomes. Specific topics include Pathogenesis and Epidemiology, Initial Evaluation, Imaging, Preoperative and Perioperative Care, Surgical Planning and Parathyroidectomy, Adjuncts and Approaches, Outcomes, and Reoperation.

CONCLUSIONS

Evidence-based guidelines were created to assist clinicians in the optimal management of secondary and tertiary renal hyperparathyroidism.

Bone and Mineral Disorder in Renal Transplant Patients: Overview of Pathology, Clinical, and Therapeutic Aspects

Renal transplantation (RTx) allows us to obtain the resolution of the uremic status but is not frequently able to solve all the metabolic complications present during end-stage renal disease. Mineral and bone disorders (MBDs) are frequent since the early stages of chronic kidney disease (CKD) and strongly influence the morbidity and mortality of patients with CKD. Some mineral metabolism (MM) alterations can persist in patients with RTx (RTx-p), as well as in the presence of complete renal function recovery. In those patients, anomalies of calcium, phosphorus, parathormone, fibroblast growth factor 23, and vitamin D such as bone and vessels are frequent and related to both pre-RTx and post-RTx specific factors. Many treatments are present for the management of post-RTx MBD. Despite that, the guidelines that can give clear directives in MBD treatment of RTx-p are still missed. For the future, to obtain an ever-greater individualisation of therapy, an increase of the evidence, the specificity of international guidelines, and more uniform management of these anomalies worldwide should be expected. In this review, the major factors related to post-renal transplant MBD (post-RTx-MBD), the main mineral metabolism biochemical anomalies, and the principal treatment for post-RTx MBD will be reported.

Tertiary and Postrenal Transplantation Hyperparathyroidism

Patients who have undergone kidney transplantation (KTx) (KTxps) are a distinctive population characterized by the persistence of some metabolic anomalies present during end-stage renal disease. Mineral metabolism (MM) parameters are frequently altered after KTx. These alterations involve calcium, phosphorus, vitamin D, and parathormone (PTH) disarrangements. At present, there is little consensus about the correct monitoring and management of PTH disorders in KTxps. This article presents the prevalence and epidemiologic and clinical impact of post-KTx hyper-PTH. The principal biochemical and instrumental investigations and the therapeutic options for these conditions are also reported.