Secondary hyperparathyroidism: pathogenesis, disease progression, and therapeutic options

Secondary hyperparathyroidism due to chronic kidney disease and access to clinical treatment and parathyroidectomy in Brazil: a nationwide survey

INTRODUCTION

Chronic kidney disease (CKD) may lead to secondary hyperparathyroidism (SHP) and its treatment is based on the control of hyperphosphatemia, hypocalcemia, and serum parathormone hormone levels (PTH) levels. Despite the advances in SHP treatment, therapeutic failure is frequent and CKD patients on dialysis require parathyroidectomy (PTx).

AIM

To update the 2011 survey, estimate the current prevalence of SHP in Brazilian dialysis centers, verify access to drugs, and identify obstacles to performing PTx.

METHODS

A questionnaire was sent to active dialysis facilities. The results were compiled and statistically compared (p < 0.05).

RESULTS

A total of 114 facilities successfully responded to the questionnaire, most of them in the Southeast region. Approximately 9% of the individuals (23,535) had serum PTH levels measurements above 1,000 pg/mL (10.7% were reported in the 2011 survey). A considerable number of the reported difficulties indicated limited availability of pivotal medications for SHP management and the associated complications. Of note, only 2.7% of the individuals were submitted to PTx. For those with PTx indication, the waiting time for the procedure was over two years in 28% of the cases. The main barriers to performing PTx were reported to be the long waiting time for PTx, the shortage of head and neck surgeons, and the lack of ward beds for hospital admissions.

CONCLUSION

Some aspects have improved since 2011. However, SHP remains highly prevalent in Brazil, and a significant number of individuals do not have access to PTx or experience long waiting times for this surgical procedure while facing substantial difficulties in obtaining clinical treatment.

Inhibition of MALAT1 facilitates ROS accumulation via the Keap1/HO-1 pathway to enhance photodynamic therapy in secondary hyperparathyroidism

The prevalence of secondary hyperparathyroidism (SHPT) in advanced chronic kidney disease (CKD) exceeds 80 %. Our previous study indicated that photodynamic therapy (PDT) has potential for treating SHPT. Long noncoding RNA (lncRNA) is involved in various oxidative stress and apoptotic processes, but the molecular mechanism remains unreported. In this study, we found that PDT induced apoptosis in SHPT through reactive oxygen species (ROS) accumulation. The expression of metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) and heme oxygenase 1 (HO-1) within SHPT was upregulated after PDT. Inhibition of MALAT1 increased PDT-induced ROS, which promoted the apoptosis. Pearson correlation analysis confirmed that there was a positive correlation between MALAT1 and HO-1, and MALAT1 inhibition down-regulated HO-1, whereas concomitant overexpression of HO-1 was able to eliminate the PDT-induced ROS and inhibit apoptosis. The direct binding of MALAT1 to Kelch-like ECH-associated protein 1 (Keap1) protein was confirmed by high-throughput sequencing, RNA pulldown, silver staining and western blotting assays. Si-Keap1 was able to rescue the down-regulation of HO-1 caused by MALAT1 inhibition, restoring the elimination of ROS by HO-1 and attenuating the effect of PDT. In addition, PDT effectively reduced parathyroid hormone (PTH) secretion in SHPT rats, and this effect was further enhanced in combination with MALAT1 inhibitors. Overall, MALAT1 activates downstream HO-1 expression by binding to Keap1, thereby reducing ROS and inhibiting apoptosis, which in turn mediates PDT resistance in SHPT. Inhibition of MALAT1 significantly enhanced the efficacy of PDT, suggesting a potential therapeutic target for improving PDT for SHPT outcomes.

Using machine learning models for predicting monthly iPTH levels in hemodialysis patients

BACKGROUND AND OBJECTIVE

Intact parathyroid hormone (iPTH), also known as active parathyroid hormone, is an important indicator commonly for monitoring secondary hyperparathyroidism (SHPT) in patients undergoing hemodialysis. The aim of this study was to use machine learning (ML) models to predict monthly iPTH levels in patients undergoing hemodialysis.

METHODS

We conducted a retrospective study on patients undergoing regular hemodialysis. Patients' blood examinations data was collected from Taiwan Society of Nephrology - Kidney Dialysis, Transplantation (TSN-KiDiT) registration system, and patients' medications data was collected from Pingtung Christian Hospital (PTCH), Taiwan. We used five different ML models to classify patients into three distinct categories based on their iPTH levels: iPTH < 150, iPTH ≥ 150 & iPTH < 600, and iPTH ≥ 600(pg/ml).

RESULTS

We ultimately included 1,351 patients in our study and processed the data in four different ways. These methods varied based on the duration of the data (either using data from just one month or continuously over three months) and the number of features used (either all 52 features or only 20 most important features identified by SHapley Additive exPlanations (SHAP) analysis). The XGBoost model, using data from a continuous three-month period and all available features, yielded the best Weighted AUROC (0.922).

CONCLUSIONS

ML is highly effective in predicting iPTH levels in hemodialysis patients, notably accurate for those with iPTH over 600 pg/ml. This method enables early identification of high-risk patients, reducing reliance on retrospective blood test assessments. Future research should focus on advancing explainable AI methods to foster clinicians' trust, and developing adaptable ML frameworks that could seamlessly integrate with existing healthcare systems.

Etelcalcetide: What we know eight years since its approval

INTRODUCTION AND OBJECTIVES

The impact of etelcalcetide on patients with chronic kidney disease (CKD) and secondary hyperparathyroidism (SHPT) has been studied since its introduction in 2016/2017. However, only a handful of studies reported clinically relevant outcomes. This narrative review aims to summarize the published data about etelcalcetide, focusing on biochemical, cardiovascular (CV) and bone endpoints, as well as adverse effects and all-cause mortality.

MATERIALS AND METHODS

A literature review of the use of etelcalcetide in hemodialysis patients with SHPT was conducted. Several sources were used, such as PubMed, Google Scholar and Cochrane Library.

RESULTS

Regarding bone and mineral metabolism, etelcalcetide is effective in reducing serum levels of parathormone (PTH), calcium, phosphate and fibroblast growth factor 23 (FGF23). Preliminary data have highlighted its role in reducing bone turnover and improving mineralization and preservation of bone structure, indicating a possible positive impact on renal osteodystrophy. From a CV perspective, etelcalcetide is associated with a significant reduction in left ventricular hypertrophy. In addition, etelcalcetide reduces FGF23 and increases sclerostin serum levels. This data suggests a possible CV beneficial effect.

CONCLUSIONS

Etelcalcetide is effective in controlling SHPT. Promising data is available for some bone and surrogate cardiovascular endpoints, suggesting a possible beneficial effect. There is a lack of studies specifically designed to evaluate its role in reducing fractures, CV and all-cause mortality.

Practice patterns on the management of secondary hyperparathyroidism in the United States: Results from a modified Delphi panel

BACKGROUND

Secondary hyperparathyroidism (SHPT) is common in patients with chronic kidney disease (CKD). Many recommendations in the Kidney Disease Improving Global Outcomes (KDIGO) CKD-mineral and bone disorder guidelines are supported by modest evidence and predate the approval of newer agents. Therefore, an expert panel defined consensus SHPT practice patterns in the United States with real-world context from the nephrology community.

METHODS

Ten US healthcare providers and one patient participated in a modified Delphi method comprising three phases. Consensus was determined via iterative responses to a questionnaire based on the 2009 and 2017 KDIGO guidelines and published literature on the identification, evaluation, monitoring, and interventional strategies for patients with SHPT. The threshold for consensus was 66% agreement.

RESULTS

Panelists generally agreed with KDIGO recommendations, with some differences. Consensus was reached on 42/105 (40%), 95/105 (90.5%), and 105/105 (100%) questions after phases 1, 2, and 3, respectively. Panelists unanimously agreed that SHPT treatment is often started late. There was a preference for serum phosphate level <4.6 mg/dL, and consensus to maintain serum calcium levels <9.5 mg/dL. There was unanimous agreement for vitamin D analogues as first-line options in patients not on dialysis with severe, progressive SHPT and unanimous preference for intravenous calcimimetic, etelcalcetide, in appropriate in-center dialysis patients. Factors such as formularies, dialysis center protocols, and insurance were recognized to influence therapeutic strategies.

CONCLUSIONS

Expert consensus was reached on SHPT management, further defining therapeutic strategies and medication use and emphasizing need for treatment early. Despite evidence-based treatment preferences supported by clinical experience, factors other than scientific evidence influence decision making, particularly with medications.

A Rare Presentation of Fahr's Syndrome Associated With Secondary Hyperparathyroidism

Fahr's syndrome (FS) is a rare disorder characterized by intracerebral calcification, presenting with various neuropsychiatric symptoms. This case highlights a rare presentation of FS with secondary hyperparathyroidism. It underscores the importance of comprehensive evaluation of early symptoms, effective use of diagnostic procedures, and proper management of symptoms.

A Nomogram for Predicting Secondary Hyperparathyroidism after Bariatric Surgery: A Retrospective Study on Short-Term Outcome

BACKGROUND

Secondary hyperparathyroidism (SHPT) is a condition that may occur after bariatric surgery. This study aimed to evaluate clinical factors that could predict SHPT after bariatric surgery and to construct a nomogram.

METHODS

Data for 294 patients were retrieved and divided into training and validation cohorts (206 and 88 patients, respectively). Univariate analysis and multivariate logistic regression were used to evaluate prognostic factors to establish a nomogram. Receiver operating characteristic (ROC) curves, calibration curves and decision curves were drawn to determine the predictive ability of our model.

RESULTS

Preoperative parathyroid hormone (PTH), fasting blood glucose (Glu0h), high-density lipoprotein cholesterol (HDL-C), creatinine, and 25(OH) vitamin D (25(OH)D) were identified as essential factors in SHPT, and their combination in the multivariate regression had good performance. Based on the multivariate model, we established a nomogram with a low degree of overfitting, as validated in the training (area under the curve: 0.743) and validation (area under the curve: 0.726) cohorts, which showed good discrimination. The calibration and decision curves also indicated that with a definite threshold, using the nomogram to predict SHPT was more beneficial.

CONCLUSIONS

The nomogram constructed in this study performed well in predicting short-term SHPT after bariatric surgery.

The Challenge of Fractures in Patients With Chronic Kidney Disease

OBJECTIVE

People with chronic kidney disease (CKD) are at increased risk of fractures in comparison to the non-CKD population, and fractures are associated with high mortality and worsening quality of life. However, the approach for evaluation of bone disease and fracture risk in CKD is different from the approach in the general population.

METHODS

The authors conducted a literature review of PubMed to include studies on pathophysiology of CKD mineral bone disorder, fracture risk assessment, and therapeutic options in the setting of CKD.

RESULTS

The higher risk observed in the CKD population is related to the complex interplay of changes in bone turnover (T), mineralization (M), and volume (V), along with other risk factors accumulated as glomerular filtration rate declines. The diagnosis of the type of renal osteodystrophy is not based only on assessment of bone density and traditional risk factors for osteoporosis. There are limitations of currently available fracture risk tools in the CKD population. Treatment choice should take into consideration the 3 components of the TMV classification along with the stage of kidney disease and comorbidities, but the assessment of these components has not been well established.

CONCLUSIONS

Current data are limited on efficacy and safety of treatments for fracture prevention in CKD. As new medications for the treatment of osteoporosis become available, there is an urgency to establish more clear guidelines for the diagnosis, fracture risk stratification, and treatment of bone disease in CKD.

Efficacy and safety of radiofrequency ablation for secondary hyperparathyroidism: a systematic review and meta-analysis

Background

Secondary hyperparathyroidism (SHPT) is a common complication of chronic kidney disease (CKD) that affects approximately 90% of end-stage renal disease and poses a significant threat to long-term survival and quality of life in patients.

Objectives

To assess whether radiofrequency ablation (RFA) is a productive and low-risk treatment for hyperparathyroidism secondary to CKD.

Methods

Embase, Web of Science, Cochrane Library, and PubMed were searched independently by two authors. The results after RFA and baseline biochemical indicators were compared, and parathyroid hormone (PTH), serum calcium, and serum phosphorus levels were the major outcomes.

Results

Four retrospective studies were screened out from 147 original literature and involved 118 cases. After RFA, serum PTH levels (1 d standardized mean difference [SMD] = -2.30, 95% confidence interval [CI] = from -3.04 to -1.56, P < 0.0001; 6 months SMD = -2.15, 95% CI = from -3.04 to -1.26, P < 0.0001; 12 months SMD = -2.35, 95% CI = from -3.52 to -1.17, P < 0.0001), serum calcium levels (1 d SMD = -1.49, 95% CI = from -2.18 to -0.81, P = 0.0001; 6 months SMD = -1.09, 95% CI = from -1.51 to -0.68, P < 0.0001), and serum phosphorus levels (1 d SMD = -1.37, 95% CI = from -1.67 to -1.07, P < 0.0001; 6 months SMD = -1.06, 95% CI = from -1.35 to -0.78, P < 0.0001) decreased significantly.

Conclusions

RFA, the newest thermal ablation technique, can effectively and safely treat hyperparathyroidism secondary to CKD. Hoarseness is the most common complication but is reversed within 6 months.

The association between bone density of lumbar spines and different daily protein intake in different renal function

BACKGROUND

Low protein intake (LPI) has been suggested as a treatment for chronic kidney disease (CKD). However, protein intake is essential for bone health.

METHODS

We studied the database of the National Health and Nutrition Examination Survey, 2005-2010. Basic variables, metabolic diseases, and bone density of different femoral areas were stratified into four subgroups according to different protein intake (DPI) (that is, <0.8, 0.8-1.0, 1.0-1.2, and >1.2 g/kg/day).

RESULTS

Significant differences were found among all lumbar area bone mineral density (BMD) and T-scores (p < 0.0001). There was an apparent trend between a decreasing BMD in the CKD groups with increasing DPI in all single lumbar spines (L1, L2, L3, and L4) and all L spines (L1-L4). Compared with DPI (0.8-1.0 g/day/kg), higher risks of osteoporosis were noticed in the subgroup of >1.2 g/day/kg over L2 (relative risk (RR)=1.326, 95% confidence interval (CI)=1.062-1.656), subgroup >1.2 g/day/kg over L3 (RR = 1.31, 95%CI = 1.057-1.622), subgroup <0.8 g/day/kg over L4 (RR = 1.276, 95%CI = 1.015-1.605), subgroup <0.8 g/day/kg over all L spines (RR = 11.275, 95%CI = 1.051-1.548), and subgroup >1.2 g/day/kg over all L spines (RR = 0.333, 95%CI = 1.098-1.618). However, a higher risk of osteoporosis was observed only in the non-CKD group. There was an apparent trend of higher DPI coexisting with lower BMD and T scores in patients with CKD. For osteoporosis (reference:0.8-1.0 g/day/kg), lower (<0.8 g/day/kg) or higher DPI (>1.2 g/day/kg) was associated with higher risks in the non-CKD group, but not in the CKD group.

CONCLUSIONS

In the CKD group, LPI for renal protection was safe without threatening L spine bone density and without causing a higher risk of osteoporosis.

Improved Clinical Outcomes Associated With Hungry Bone Syndrome Following Parathyroidectomy in Dialysis Patients

OBJECTIVE

Hungry bone syndrome (HBS) is a common complication after parathyroidectomy in dialysis patients with severe secondary hyperparathyroidism. The rapid decline in parathyroid hormone (PTH) levels diminishes bone resorption and accelerates bone formation. This causes a significant influx of calcium and phosphate into the bone, resulting in severe and prolonged hypocalcemia. While previous studies have established risk factors for HBS, the outcomes beyond the reduced recurrence rate of hyperparathyroidism have been largely unexplored.

METHODS

This single-center retrospective study analyzed 322 cases in 314 dialysis patients who underwent parathyroidectomy between 2012 and 2022. The study examined baseline factors associated with HBS, adverse events, and clinical outcomes, including changes in blood pressure and hematologic and nutritional parameters over 3-12 months of follow-up, stratified by HBS status.

RESULTS

Total parathyroidectomy was performed in 28 cases (8.7%), total parathyroidectomy with implantation in 98 cases (30.4%), and subtotal parathyroidectomy in 196 cases (60.9%). HBS occurred in 207 cases (64%). Independent predictors of HBS included male sex, lower serum calcium levels, higher PTH levels, and lack of active vitamin D treatment at baseline. Patients with HBS had longer hospital stays but did not experience an increase in other adverse events. Following parathyroidectomy, the HBS group showed a greater reduction in blood pressure and more significant increases in hemoglobin, total lymphocyte count, and serum creatinine. This group also saw a more substantial decrease in the proportions of patients with hemoglobin <11 g/dL and serum creatinine/body surface area <380 μmol/L/m2. Although the HBS group showed a more significant decline in PTH levels from baseline, similar proportions achieved the target PTH level by the end of the study. Serum calcium levels remained substantially lower in the HBS group throughout the follow-up, while serum phosphate and PTH levels were comparable.

CONCLUSION

HBS was associated with more pronounced improvements in blood pressure, anemia, and nutritional parameters. The presence of HBS could indicate greater achievement in controlling hyperparathyroidism following parathyroidectomy.

Current therapeutic approach of chronic kidney disease-mineral and bone disorder

Chronic kidney disease (CKD) has emerged as one of the leading noncommunicable diseases affecting >10% of the population worldwide. Bone and mineral disorders are a common complication among patients with CKD resulting in a poor life quality, high fracture risk, increased morbidity and cardiovascular mortality. According to Kidney Disease: Improving Global Outcomes, renal osteodystrophy refers to changes in bone morphology found in bone biopsy, whereas CKD-mineral and bone disorder (CKD-MBD) defines a complex of disturbances including biochemical and hormonal alterations, disorders of bone and mineral metabolism and extraskeletal calcification. As a result, the management of CKD-MBD should focus on the aforementioned parameters, including the treatment of hyperphosphatemia, hypocalcemia, abnormal PTH and vitamin D levels. Regarding the bone fragility fractures, osteoporosis and renal osteodystrophy, which constitute the bone component of CKD-MBD, anti-osteoporotic agents constitute the mainstay of treatment. However, a thorough elucidation of the CKD-MBD pathogenesis is crucial for the ideal personalized treatment approach. In this paper, we review the pathology and management of CKD-MBD based on the current literature with special attention to recent advances.

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.

Development and Validation of an Explainable Machine Learning Model for Identification of Hyper-Functioning Parathyroid Glands from High-Frequency Ultrasonographic Images

OBJECTIVE

To develop and validate a machine learning (ML) model based on high-frequency ultrasound (HFUS) images with the aim to identify the functional status of parathyroid glands (PTGs) in secondary hyper-parathyroidism (SHPT) patients.

METHODS

This retrospective study enrolled 60 SHPT patients (27 female, 33 male; mean age: 51.2 years) with 184 PTGs detected from February 2016 to June 2022. All enrollments underwent single-photon emission computed tomography/computed tomography and contrast-enhanced ultrasound examinations. The PTGs were randomly divided into training (n = 147) and testing datasets (n = 37). Four effective ML classifiers were used and combined models incorporating multi-modal HFUS visual signs and radiomics features was constructed based on the optimal classifier. Model performance was compared in terms of discrimination, calibration and clinical utility. The Shapley additive explanation method was used to explain and visualize the main predictors of the optimal model.

RESULTS

This model, using a random forest classifier algorithm, outperformed other classifiers. Based on optimal classifier features, the model constructed from ultrasound visual and ML features achieved a favorable performance in the prediction of hyper-functioning PTGs. Compared with the traditional visual model, the ultrasound-based ML model achieved significant (p = 0.03) improvement (area under the curve: 0.859 vs. 0.629) and higher sensitivity (100.0% vs. 94.1%) and accuracy (86.5% vs. 67.6%). Among the predictors attributed to model development, large size and high echogenic heterogeneity of PTGs in ultrasonographic images were more often associated with high risk of hyper-functioning PTGs.

CONCLUSION

The ultrasound-based ML model for identifying hyper-functioning PTGs in SHPT patients showed good performance and interpretability using high-frequency ultrasonographic images, which may facilitate clinical management.

Long-Term Efficacy and Safety of Upacicalcet in Japanese Hemodialysis Patients with Secondary Hyperparathyroidism: Open-Label 52-Week Study

INTRODUCTION

Upacicalcet is a novel injectable calcimimetic. This phase 3 multicenter open-label study aimed to assess the long-term efficacy and safety of upacicalcet in hemodialysis (HD) patients with secondary hyperparathyroidism (SHPT).

METHODS

Japanese HD patients with serum intact parathyroid hormone (iPTH) levels >240 pg/mL and corrected calcium (cCa) levels ≥8.4 mg/dL were enrolled. Upacicalcet with a dose range of 25-300 µg was administered after each dialysis for 52 weeks. The main efficacy endpoint was the percentage of patients achieving the target iPTH level (60-240 pg/mL).

RESULTS

A total of 157 patients were enrolled, of whom 138 completed the study. Overall, 94.2% of patients achieved the target serum iPTH level at week 52. Neither symptomatic hypocalcemia nor cCa level <7.5 mg/dL occurred despite the negligible increase of concomitant vitamin D receptor activators and calcium carbonate. Upacicalcet improved the control of serum phosphate (P) and calcium levels regardless of baseline PTH levels and decreased intact fibroblast growth factor-23 levels. The largest parathyroid glands shrank, irrespective of their baseline volume or prior calcimimetic usage. Upacicalcet was well tolerated, with no adverse events requiring dose reduction.

CONCLUSION

This is the first study to show that a calcimimetic improves serum P and cCa control without inducing severe hypocalcemia in patients with iPTH levels ≤300 pg/mL. Upacicalcet is efficacious in HD patients with mild-to-severe SHPT, with few safety concerns.

INTRODUCTION

Upacicalcet is a novel injectable calcimimetic. This phase 3 multicenter open-label study aimed to assess the long-term efficacy and safety of upacicalcet in hemodialysis (HD) patients with secondary hyperparathyroidism (SHPT).

METHODS

Japanese HD patients with serum intact parathyroid hormone (iPTH) levels >240 pg/mL and corrected calcium (cCa) levels ≥8.4 mg/dL were enrolled. Upacicalcet with a dose range of 25-300 µg was administered after each dialysis for 52 weeks. The main efficacy endpoint was the percentage of patients achieving the target iPTH level (60-240 pg/mL).

RESULTS

A total of 157 patients were enrolled, of whom 138 completed the study. Overall, 94.2% of patients achieved the target serum iPTH level at week 52. Neither symptomatic hypocalcemia nor cCa level <7.5 mg/dL occurred despite the negligible increase of concomitant vitamin D receptor activators and calcium carbonate. Upacicalcet improved the control of serum phosphate (P) and calcium levels regardless of baseline PTH levels and decreased intact fibroblast growth factor-23 levels. The largest parathyroid glands shrank, irrespective of their baseline volume or prior calcimimetic usage. Upacicalcet was well tolerated, with no adverse events requiring dose reduction.

CONCLUSION

This is the first study to show that a calcimimetic improves serum P and cCa control without inducing severe hypocalcemia in patients with iPTH levels ≤300 pg/mL. Upacicalcet is efficacious in HD patients with mild-to-severe SHPT, with few safety concerns.

Calcified Maxillary Fibroma in a Patient on Hemodialysis for Seven Years

Background

The presentation of mineral bone disorder (MBD) in individuals with chronic kidney disease (CKD) may vary. Consequently, physicians should be capable of recognising this condition when there is a suspicion of its existence. This case report will describe a calcified maxilla tumour as a manifestation of CKD-MBD.

Case description

Initially asymptomatic, a 32-year-old female presented with progressive swelling of the upper left jaw. She had a history of routine haemodialysis. Further laboratory, radiological, and histopathological workup revealed the mass was indeed calcified maxillary fibroma arising from the manifestation of CKD-MBD.

Conclusion

This study underscores the significance of clinical comprehension of the broad-spectrum manifestations of CKD-MBD, including an initially asymptomatic mass. In addition, the screening of the patient's biochemical was required to determine the necessity of early intervention and improve the patient's outcome.

LEARNING POINTS

The case emphasises the importance of recognising atypical presentations of chronic kidney disease-mineral bone disorder (CKD-MBD), such as a calcified mass, which are rarely reported but critical for timely intervention.This report underscores the necessity for routine screening for secondary hyperparathyroidism in CKD patients, as early detection can significantly impact patient outcomes.Surgical management of the overlying mass and underlying parathyroid gland hyperplasia should always be considered in the management of the symptomatic CKD-MBD patient.

Secondary hyperparathyroidism in chronic kidney disease: A narrative review focus on therapeutic strategy

Chronic kidney disease (CKD) affects over 10% of the global population. One crucial complication of CKD is secondary hyperparathyroidism (SHPT), marked by elevated parathyroid hormone levels due to hyperphosphataemia, hypocalcaemia, and low active vitamin D from impaired renal function. SHPT increases risks of bone deformities, vascular calcification, cardiovascular events and mortality. This review examines SHPT treatment strategies in patients with CKD. First-line treatments include phosphate binders, vitamin D receptor activators and calcimimetics. When these fail, invasive options like parathyroidectomy (PTX) and thermal ablation are considered. PTX effectively reduces symptoms and improves radiological outcomes, outperforming medical treatment alone in reducing cardiovascular risk and mortality. Thermal ablation techniques, such as microwave, radiofrequency, laser or high-intensity focused ultrasound, offer less invasive alternatives with promising results. Future research should explore the molecular mechanisms of parathyroid gland hyperplasia and evaluate various treatments' impacts.

Secondary hyperparathyroidism in chronic kidney disease: pathophysiology, current treatments and investigational drugs

INTRODUCTION

Secondary hyperparathyroidism (SHPT) is a common complication of chronic kidney disease (CKD). It begins as an adaptive increase in parathyroid hormone levels to prevent calcium and phosphate derangements. Over time, this condition becomes maladaptive and is associated with increased morbidity and mortality. Current therapies encompass phosphate-lowering strategies, vitamin D analogues, calcimimetics and parathyroidectomy. These approaches harbor inherent limitations, stimulating interest in the development of new drugs for SHPT to overcome these limitations and improve survival and quality of life among CKD patients.

AREAS COVERED

This review delves into the main pathophysiological mechanisms involved in SHPT, alongside the treatment options that are currently available and under active investigation. Data presented herein stem from a comprehensive search conducted across PubMed, Web of Science, ClinicalTrials.gov and International Clinical Trials Registry Platform (ICTRP) spanning from 2000 onwards.

EXPERT OPINION

The advancements in investigational drugs for SHPT hold significant promise for enhancing treatment efficacy while minimizing side effects associated with conventional therapies. Although several challenges still hinder their adoption in clinical practice, ongoing research will likely continue to expand the available therapeutic options, refine treatment strategies, and tailor them to individual patient profiles.

Secondary hyperparathyroidism: Predictors and relationship with vitamin D status, bone turnover markers and bone mineral density

INTRODUCTION

Secondary hyperparathyroidism (SHPT) has adverse implications for bone health but is relatively understudied. In this study we examine the prevalence and determinants of SHPT and describe the relationship of SHPT with bone turnover markers and bone mineral density (BMD) in older Irish adults.

METHOD

Eligible participants (n = 4139) were identified from the Trinity-Ulster-Department of Agriculture (TUDA) study, a cohort of Irish adults aged ≥60 years. Exclusion criteria included an estimated glomerular filtration rate (eGFR) <30 ml/min and serum calcium >2.5 mmol/l to remove hyperparathyroidism due to advanced chronic kidney disease (CKD) and primary hyperparathyroidism respectively. The relationship between SHPT and bone turnover markers and BMD (measured by densitometry) was examined in a subsample (n = 1488). Vitamin D deficiency was defined as 25-hydroxyvitamin D [25 (OH)D] <30 nmol/l.

RESULTS

Participants had a mean age of 73.6 ± 7.9 years, 65.1 % were female and 19.4 % were found to be vitamin D deficient. The prevalence of SHPT decreased as vitamin D increased, from 30.6 % in those deficient to 9.8 % in those with 25(OH)D ≥ 50 nmol/l and increased with declining kidney function. In non‑calcium supplement users, principal determinants of SHPT were vitamin D deficiency (OR 4.18, CI 3.05-5.73, p < 0.001), eGFR 30-44 ml/min (OR 3.69, CI 2.44-5.57, p < 0.001), loop diuretic use (OR 3.52, CI 2.59-4.79, p < 0.001) and to a lesser extent body mass index (p = 0.001), eGFR 45-59 ml/min (p < 0.001) and 25(OH)D level 30-49 nmol/l (p = 0.002). Similar findings were observed in calcium supplement users, though proton pump inhibitors were also associated with SHPT (OR 1.55, CI 1.08-2.22, p = 0.018) while vitamin D 30-49 nmol/l was not. In participants with SHPT versus those without, bone turnover markers were higher: bone alkaline phosphatase (p = 0.017) and tartrate-resistant acid phosphatase (p = 0.033), whilst there was lower BMD at the neck of femur (0.880 vs. 0.903 g/cm2, p = 0.033) and total hip (0.968 vs. 0.995 g/cm2, P = 0.017).

DISCUSSION

The results show that up to one in six older Irish adults had SHPT and this was associated with lower BMD and higher concentrations of bone turnover markers. Both vitamin D deficiency and 25(OH)D level 30-49 nmol/l were important predictors of SHPT. Loop diuretics and PPIs may also increase the risk of SHPT, and their use may need to be carefully considered in this population. Further studies examining the potential impact of these factors on bone health in similar populations to our study sample are warranted.

Brown tumors: Retrospective analysis of 26 cases

INTRODUCTION

Brown tumors are reactive osteolytic lesions caused by hyperparathyroidism. These rare lesions are non-neoplastic processes that result from bone resorption. The purpose of this study was to retrospectively review a 34-year experience with brown tumors in our institution.

MATERIALS AND METHODS

We retrospectively analyzed the records of 26 consecutive patients with brown tumor who were treated in our institution between May 1988 and October 2020, with a mean follow-up of 36,1 months.

RESULTS

17 male (65,4%) and 9 female (34,6%) patients with a mean age of 41,6 were included in the study. Localized bone pain was present in 13 cases (50,0%) as the first presenting symptom. 3 patients (11,5%) presented with diffuse bone pain. 7 patients (26,9%) were diagnosed with brown tumor while being investigated for pathological fractures. The other 3 patients (11,5%) were diagnosed while being evaluated for hypercalcemia symptoms. 7 patients (26,9%) had solitary lesions, while 19 patients (73,1%) had multiple lesions. Pelvis, femur, ribs, tibia, proximal humerus and mandible were the most common sites of localization. 23 patients (88,5%) were diagnosed with primary hyperparathyroidism, while the other 3 patients (11,5%) had secondary hyperparathyroidism. A total of the 65 lesions, 23 (35.4%) underwent orthopedic surgery, and 42 (64.6%) were followed up conservatively after parathyroidectomy. Orthopedic surgery was performed in 21 of 26 patients, the other 5 cases were followed up conservatively. Intralesional curettage was performed in 19 cases (82,6%). The resulting cavity was filled with bone cement in 11 cases (47,8%). Bone grafting was applied in 8 cases (34,8%). No recurrence was observed in any of the patients.

CONCLUSION

The diagnosis of brown tumor begins with clinical suspicion. Endocrinology and general surgery consultation is important before surgery. Treatment of brown tumors requires a multidisciplinary approach.

Persisting Hypercalcemia and Hyperparathyroidism after Kidney Transplantation Have a Negative Impact on Graft and Patient Survival

Hyperparathyroidism (HPT) with hypercalcemia, often deemed irreversible and detrimental to graft survival post-kidney transplantation (KT), prompts pre-transplant parathyroidectomy in hypercalcemic patients. In this retrospective analysis of 1212 kidney transplant recipients (KTRs) between 2006 and 2019, the incidence and effect of persistent HPT and hypercalcemia on graft and patient survival, and risk factors for persistence were analyzed until 60 months of follow up (FU). At KT, 5.7% (n = 69) had no HPT, 32.7% (n = 396) had HPT without hypercalcemia and 37.0% (n = 448) had HPT with hypercalcemia. At 2 years FU, 26.4% (n = 320) of patients had no HPT and 6% (n = 73) had HPT with hypercalcemia. Dialysis and dialysis duration were linked to HPT development, while dialysis, KT waiting time and donor type correlated with persisting hypercalcemia after KT. KTRs with normalized PTH and recovered hypercalcemia had improved death-censored graft survival (p < 0.001) and overall patient survival (p < 0.001). HPT with hypercalcemia is frequent at time of KT with normalization of PTH and calcium in a substantial proportion of patients after a KT. These findings question the routine pre-KT parathyroidectomy for suspected parathyroid autonomy. Persisting HPT, especially with hypercalcemia, adversely affects graft and patient survival, suggesting the need for more aggressive treatment of HPT, especially in cases of persisting hypercalcemia.

Bone mineral density and related clinical and laboratory factors in peritoneal dialysis patients: Implications for bone health management

BACKGROUND

End-stage renal disease (ESRD) patients often experience accelerated bone turnover, leading to osteoporosis and osteopenia. This study aimed to determine the prevalence of osteoporosis in Peritoneal Dialysis (PD) patients using bone mineral density (BMD) measurements obtained through dual-energy X-ray absorptiometry (DEXA) scan and to explore any possible associations with clinical and biochemical factors.

METHODS

In this cross-sectional study, we enrolled 76 peritoneal dialysis patients from the dialysis center at An-Najah National University Hospital in Nablus, Palestine. We used the DEXA scan to measure BMD at the lumbar spine and hip, with values expressed as T-scores. We conducted a multivariate analysis to explore the relationship between BMD and clinical and biochemical parameters.

RESULTS

Over half (52.6%) of the PD patients had osteoporosis, with a higher prevalence observed among patients with lower BMI (p<0.001). Higher alkaline phosphatase levels were found among osteoporotic patients compared to non-osteoporotic patients (p = 0.045). Vitamin D deficiency was also prevalent in this population, affecting 86.6% of patients. No significant correlation was found between 25 vitamin D levels and BMD. No significant correlation was found between Parathyroid hormone (PTH) levels and BMD.

CONCLUSION

A notable proportion of PD patients experience reduced BMD. Our study found no correlation between vitamin D levels and BMD, but it highlighted the significant vitamin D deficiency in this population. Furthermore, our analysis indicated a positive correlation between BMI and BMD, especially in the femoral neck area. This underscores the significance of addressing bone health in PD patients to mitigate the risk of fractures and improve their overall well-being.

Vitamin D: A Bridge between Kidney and Heart

Chronic kidney disease (CKD) and cardiovascular disease (CVD) are highly prevalent conditions, each significantly contributing to the global burden of morbidity and mortality. CVD and CKD share a great number of common risk factors, such as hypertension, diabetes, obesity, and smoking, among others. Their relationship extends beyond these factors, encompassing intricate interplay between the two systems. Within this complex network of pathophysiological processes, vitamin D has emerged as a potential linchpin, exerting influence over diverse physiological pathways implicated in both CKD and CVD. In recent years, scientific exploration has unveiled a close connection between these two prevalent conditions and vitamin D, a crucial hormone traditionally recognized for its role in bone health. This article aims to provide an extensive review of vitamin D's multifaceted and expanding actions concerning its involvement in CKD and CVD.

The Molecular Mechanisms Underlying the Systemic Effects Mediated by Parathormone in the Context of Chronic Kidney Disease

Chronic kidney disease (CKD) stands as a prominent non-communicable ailment, significantly impacting life expectancy. Physiopathology stands mainly upon the triangle represented by parathormone-Vitamin D-Fibroblast Growth Factor-23. Parathormone (PTH), the key hormone in mineral homeostasis, is one of the less easily modifiable parameters in CKD; however, it stands as a significant marker for assessing the risk of complications. The updated "trade-off hypothesis" reveals that levels of PTH spike out of the normal range as early as stage G2 CKD, advancing it as a possible determinant of systemic damage. The present review aims to review the effects exhibited by PTH on several organs while linking the molecular mechanisms to the observed actions in the context of CKD. From a diagnostic perspective, PTH is the most reliable and accessible biochemical marker in CKD, but its trend bears a higher significance on a patient's prognosis rather than the absolute value. Classically, PTH acts in a dichotomous manner on bone tissue, maintaining a balance between formation and resorption. Under the uremic conditions of advanced CKD, the altered intestinal microbiota majorly tips the balance towards bone lysis. Probiotic treatment has proven reliable in animal models, but in humans, data are limited. Regarding bone status, persistently high levels of PTH determine a reduction in mineral density and a concurrent increase in fracture risk. Pharmacological manipulation of serum PTH requires appropriate patient selection and monitoring since dangerously low levels of PTH may completely inhibit bone turnover. Moreover, the altered mineral balance extends to the cardiovascular system, promoting vascular calcifications. Lastly, the involvement of PTH in the Renin-Angiotensin-Aldosterone axis highlights the importance of opting for the appropriate pharmacological agent should hypertension develop.

Extended-Release Calcifediol: A Data Journey from Phase 3 Studies to Real-World Evidence Highlights the Importance of Early Treatment of Secondary Hyperparathyroidism

BACKGROUND

Early secondary hyperparathyroidism (SHPT) diagnosis and treatment are crucial to delay the progression of SHPT and related complications, in particular, cardiovascular events and bone fractures. Extended-release calcifediol (ERC) has been developed for the treatment of SHPT in patients with stage 3/4 chronic kidney disease (CKD) and vitamin D insufficiency (VDI).

SUMMARY

This review compares baseline characteristics and treatment responses of SHPT patients receiving ERC in phase 3 studies with those treated with ERC in a real-world study. Mean ± standard deviation baseline parathyroid hormone (PTH) levels were 147 ± 56 pg/mL and 148 ± 64 pg/mL in the phase 3 ERC cohorts, and 181 ± 98 pg/mL in the real-world study. Other baseline laboratory parameters were consistent between the clinical and real-world studies. ERC treatment increased 25-hydroxyvitamin D (25(OH)D) and significantly reduced PTH levels, regardless of baseline CKD stage, in all studies. In the pooled phase 3 per-protocol populations, 74% of the ERC cohort were uptitrated to 60 μg/day after 12 weeks at 30 μg/day, 97% attained 25(OH)D levels ≥30 ng/mL, and 40% achieved ≥30% PTH reduction. Despite a much lower rate of uptitration in the real-world study, 70% of patients achieved 25(OH)D levels ≥30 ng/mL, and 40% had a ≥30% reduction in PTH.

KEY MESSAGES

These data establish a "continuum" of clinical and real-world evidence of ERC effectiveness for treating SHPT, irrespective of CKD stage, baseline PTH levels, and ERC dose. This evidence supports early treatment initiation with ERC, following diagnosis of SHPT, VDI, and stage 3 CKD, to delay SHPT progression.

Parathyroidectomy: still the best choice for the management of severe secondary hyperparathyroidism

INTRODUCTION

Management of secondary hyperparathyroidism (SHPT) is a challenging endeavor with several factors contruibuting to treatment failure. Calcimimetic therapy has revolutionized the management of SHPT, leading to changes in indications and appropriate timing of parathyroidectomy (PTX) around the world.

METHODS

We compared response rates to clinical vs. surgical approaches to SHPT in patients on maintenance dialysis (CKD 5D) and in kidney transplant patients (Ktx). A retrospective analysis of the one-year follow-up findings was carried out. CKD 5D patients were divided into 3 groups according to treatment strategy: parathyroidectomy, clinical management without cinacalcet (named standard - STD) and with cinacalcet (STD + CIN). Ktx patients were divided into 3 groups: PTX, CIN (cinacalcet use), and observation (OBS).

RESULTS

In CKD 5D we found a significant parathormone (PTH) decrease in all groups. Despite all groups had a higher PTH at baseline, we identified a more pronounced reduction in the PTX group. Regarding severe SHPT, the difference among groups was evidently wider: 31%, 14% and 80% of STD, STD + CIN, and PTX groups reached adequate PTH levels, respectively (p<0.0001). Concerning the Ktx population, although the difference was not so impressive, a higher rate of success in the PTX group was also observed.

CONCLUSION

PTX still seems to be the best treatment choice for SHPT, especially in patients with prolonged diseases in unresourceful scenarios.

Renal hyperparathyroidism- a risk factor in the development of encapsulating peritoneal sclerosis

Background

Encapsulating peritoneal sclerosis (EPS) is a rare complication of prolonged peritoneal dialysis (PD) exposure, characterised by peritoneal thickening, calcification, and fibrosis ultimately presenting with life-threatening bowel obstruction. The presence or role of peritoneal calcification in the pathogenesis of EPS is poorly characterised. We hypothesise that significantly aberrant bone mineral metabolism in patients on PD can cause peritoneal calcification which may trigger the development of EPS. We compared the temporal evolution of bone mineral markers during PD in EPS patients with non-EPS long-term PD controls.

Methods

Linear mixed model and logistic regression analysis were used to compare four-monthly serum levels of calcium, phosphate, parathyroid hormone, and alkaline phosphatase (ALP) over the duration of PD exposure in 46 EPS and 46 controls (PD, non-EPS) patients.

Results

EPS patients had higher mean calcium (2.51 vs. 2.41 mmol/L) and ALP (248.00 vs. 111.13 IU/L) levels compared with controls (p=0.01 and p<0.001 respectively, maximum likelihood estimation). Logistic regression analysis demonstrated that high serum calcium and phosphate levels during PD were associated with a 4.5 and 2.9 fold increase in the risk of developing EPS respectively.

Conclusion

High levels of calcium and phosphate in patients on PD were identified to be risk factors for EPS development. Possible reasons for this may be an imbalance of pro-calcifying factors and calcification inhibitors promoting peritoneal calcification which increases peritoneal stiffness. Mechanical alterations may trigger, unregulated fibrosis and subsequent development of EPS. Improved management of secondary hyperparathyroidism during PD may ultimately diminish the EPS risk.

Single-cell RNA sequencing reveals transdifferentiation of parathyroid chief cells into oxyphil cells in patients with uremic secondary hyperparathyroidism

The parathyroid gland is one of the main organs that regulate calcium and phosphorus metabolism. It is mainly composed of chief cells and oxyphil cells. Oxyphil cell counts are low in the parathyroid glands of healthy adults but are dramatically increased in patients with uremia and secondary hyperparathyroidism (SHPT). Increased oxyphil cell counts are related to drug treatment resistance, but the origin of oxyphil cells and the mechanism of proliferation remain unknown. Herein, three types of parathyroid nodules (chief cell nodules, oxyphil cell nodules and mixed nodules, respectively) excised from parathyroid glands of uremic SHPT patients were used for single-cell RNA sequencing (scRNA-seq), other molecular biology studies, and transplantation into nude mice. Through scRNA-seq of parathyroid mixed nodules from three patients with uremic SHPT, we established the first transcriptomic map of the human parathyroid and found a chief-to-oxyphil cell transdifferentiation characterized by gradual mitochondrial enrichment associated with the uremic milieu. Notably, the mitochondrial enrichment and cellular proliferation of chief cell and oxyphil cell nodules decreased significantly after leaving the uremic milieu via transplantation into nude mice. Remarkably, the phenotype of oxyphil cell nodules improved significantly in the nude mice as characterized by decreased mitochondrial content and the proportion of oxyphil cells to chief cells. Thus, our study provides a comprehensive single-cell transcriptome atlas of the human parathyroid and elucidates the origin of parathyroid oxyphil cells and their underlying transdifferentiating mechanism. These findings enhance our understanding of parathyroid disease and may open new treatment perspectives for patients with chronic kidney disease.

Pharmacokinetics, Pharmacodynamics, and Safety of Evocalcet (KHK7580), a Novel Calcimimetic Agent: An Open-Label, Single- and Multiple-Dose, Phase I Trial in Healthy Chinese Subjects

Purpose

This study explored the pharmacokinetics (PK), pharmacodynamics (PD), and safety of evocalcet (KHK7580), a new calcimimetic agent, in healthy Chinese subjects following single and multiple doses.

Methods

This was a single-center, open-label phase I trial conducted in China. The study started from the single-dose cohorts (1, 3, 6, 12 mg evocalcet, step-by-step administration) and proceeded to the multiple-dose cohort (6 mg evocalcet once daily for eight days). Blood and urine samples were collected at the designated time points for pharmacokinetic and pharmacodynamic analysis. Safety was evaluated by treatment-emergent adverse events (TEAEs), clinical laboratory tests, vital signs, electrocardiograms (ECGs), and ophthalmological examination.

Results

Among 42 enrolled subjects, eight in each single-dose cohort and 10 in multiple-dose cohort, 40 subjects completed the study. In single-dose cohorts, tmax was 1.00-2.00 h and declined biphasically. The mean t1/2 was 15.99-20.84 h. Evocalcet exposure in AUC0-inf, AUC0-t, and Cmax showed a dose-proportional increase. In the multiple-dose cohort, tmax was 2.00 h and declined biphasically after multiple administrations. The accumulation was negligible. Ctrough levels were similar across days and steady from 24 hours after the first administration. The mean t1/2 was 15.59 h. PD analysis showed that evocalcet decreased intact parathyroid hormone and corrected calcium levels in a dose-dependent manner. Seventeen (40.5%) subjects reported TEAEs. No serious or severe TEAE occurred.

Conclusion

In healthy Chinese subjects, evocalcet demonstrated dose-dependent PK and PD properties and was well-tolerated.

Predictive Risk Score for Postparathyroidectomy Hungry Bone Syndrome in Patients With Secondary Hyperparathyroidism

PURPOSE

Secondary hyperparathyroidism (SHPT) frequently affects patients with end-stage renal disease. Hungry bone syndrome (HBS) is a common complication among patients who undergo parathyroidectomy for SHPT and may cause prolonged hospitalization or require intensive care. The objective of this study is to develop a scoring system to stratify patients according to their risk of developing HBS.

METHODS

A retrospective cohort study was performed using the US Renal Data System (2010-2021). Univariable and multivariable logistic regression models were developed and weighted β-coefficients from the multivariable model were used to construct a risk score for the development of HBS. Positive and negative predictive values were assessed.

RESULTS

Of 17 074 patients who underwent parathyroidectomy for SHPT, 19.4% developed HBS. Intensive care unit admission was more common in patients who developed HBS (33.5% vs 24.6%, P < .001). On multivariable logistic regression analysis, younger age, renal osteodystrophy, longer duration of dialysis, longer duration of kidney transplant, and higher Elixhauser score were significantly associated with HBS. A risk score based on these clinical factors was developed, with a total of 6 possible points. Rates of HBS ranged from 8% in patients with 0 points to 44% in patients with 6 points. The risk score had a poor positive predictive value (20.3%) but excellent negative predictive value (89.3%) for HBS.

CONCLUSION

We developed a weighted risk score that effectively stratifies patients by risk for developing HBS after parathyroidectomy. This tool can be used to counsel patients and to identify patients who may not require postoperative hospitalization.

The Association Between Environmental Cadmium Exposure and Parathyroid Hormone Levels

Cadmium exposure is associated with renal dysfunction and bone damage. Chronic kidney disease and bone loss are also related to parathyroid hormone (PTH). However, whether cadmium exposure affect PTH level is not completely understood. In this study, we observed the association between environmental cadmium exposure and PTH levels in a Chinese population. A ChinaCd study was performed in China in 1990s which included 790 subjects living in heavily, moderately and low cadmium polluted area. 354 of them (121 men and 233 women) also had the data of serum PTH. The cadmium levels in blood (BCd) and urine (UCd) were determined by flame atomic absorption spectrometry. Serum PTH was detected by immunoradiometric assay. Renal function was assessed based on urinary N-acetyl-β-d-glucosaminidase (UNAG), β2-microglobulin (UBMG) and urinary albumin (UALB). The median BCd and UCd levels were 4.69 μg/L and 5.50 μg/g creatinine. The BCd, UCd, UNAG, UBMG and UALB levels in subjects with low PTH (< 5.0 ng/L) were significantly higher than those with PTH ≥ 5.0 ng/L (p < 0.05 or p < 0.01). Spearman correlation analysis also showed that UCd level was negatively correlated to PTH levels (r = -0.17, p = 0.008) in women. A weak correlation was also observed between PTH level and BCd in women (r = -0.11, p = 0.09) and UBMG in total population (r = -0.114, p = 0.07). Univariable and mutivariable logistic regression analysis both demonstrated that high BCd (> 10 μg/L) (odds ratio (OR) = 2.26, 95% confidence interval (CI):1.10-4.63; OR = 2.36, 95%CI: 1.11-5.05) and UCd level (> 20 μg/g cr) (OR = 2.84, 95% CI:1.32-6.10; OR = 2.97, 95%CI: 1.25-7.05) were associated with high risk of low PTH. Our data showed that environmental cadmium exposure was associated with low PTH level.

Phase 2 study of upacicalcet in Japanese haemodialysis patients with secondary hyperparathyroidism: an intraindividual dose-adjustment study

Background

Upacicalcet is a novel small-molecule calcimimetic agent developed for intravenous injection. Here, we evaluated the long-term efficacy and safety of upacicalcet treatment via intraindividual dose adjustment in haemodialysis patients with secondary hyperparathyroidism (SHPT).

Methods

A phase 2, multicentre, open-label, single-arm study was conducted. Upacicalcet was administered for 52 weeks; the starting dose was 50 μg thrice a week, and then adjusted to 25, 50, 100, 150, 200, 250, or 300 μg, according to the dose-adjustment method set in the protocol. The primary endpoint was the percentage of patients with serum intact parathyroid hormone (iPTH) level achieving a target range of 60-240 pg/mL (target achievement rate) at week 18.

Results

A total of 58 patients were administered upacicalcet. The target achievement rate of serum iPTH level at week 18 was 57.9%, which increased to 80.8% at week 52. The serum-corrected calcium (cCa) level decreased immediately after upacicalcet administration, but no further decrease was observed. Adverse events were observed in 94.8% of patients, and adverse drug reactions (ADRs) occurred in 20.7% of patients. The most common ADR was decreased adjusted calcium in eight patients; dizziness occurred as a serious ADR in one patient. The serum cCa level of patients who interrupted upacicalcet treatment at a serum cCa level of <7.5 mg/dL recovered to ≥7.5 mg/dL immediately after the interruption.

Conclusions

In haemodialysis patients with SHPT, upacicalcet doses of 25-300 μg for 52 weeks were found to be highly effective and well-tolerated, with minor safety concerns.

Advantages of total parathyroidectomy in patients with secondary hyperparathyroidism induced by end stage renal disease

Introduction

Secondary hyperparathyroidism, as a result of chronic kidney disease could be treated medically or surgically. When pharmacotherapy fails, patients undergo surgery - parathyroidectomy, the curative treatment of secondary hyperparathyroidism (SHPT). There are currently 3 accepted surgical techniques, each with supporters or opponents - total parathyroidectomy, subtotal parathyroidectomy and parathyroidectomy with immediate autotransplantation.

Methods

In this paper we described our experience on a series of 160 consecutive patients diagnosed with secondary hyperparathyroidism who underwent surgery, in 27 cases it was totalization of the intervention (patients with previously performed subtotal parathyroidectomy or with supernumerary glands and SHPT recurrence). We routinely perform total parathyroidectomy, the method that we believe offers the best results.

Results

The group of patients was studied according to demographic criteria, paraclinical balance, clinical symptomatology, pre- and postoperative iPTH (intact parathormone) values, SHPT recurrence, number of reinterventions. In 31 cases we found gland ectopy and in 15 cases we discovered supernumerary parathyroids. A percentage of 96.24% of patients with total parathyroidectomy did not show recurrence.

Discussions

After analyzing the obtained results, our conclusion was that total parathyroidectomy is the intervention of choice for patients suffering from secondary hyperparathyroidism when pharmacotherapy fails in order to prevent recurrence of the disease and to correct the metabolic parameters.

Brown Tumors of the Jaws: A Retrospective Study

Objectives

(1) Describe the clinical spectrum, imaging features, management, and outcome of brown tumors (BT) of the jaws. (2) Determine via a literature review the facts and controversies around the characteristics and management of this lesion.

Materials and methods

Our study was approved by the institutional committee of Sahloul University Hospital in accordance with the ethical standards of the Declaration of Helsinki. Sixteen patients with BT in the context of a primary, secondary, and tertiary hyperparathyroidism were treated and followed up during their recovery.

Results

This study reports 16 patients with a mean age of 48 years old. Brown tumor lesions were associated with primary hyperparathyroidism in 6 cases (38%), secondary hyperparathyroidism to chronic kidney failure in 5 cases (31%), and tertiary hyperparathyroidism in the context of a long lasting CRI in 5 cases. Their location was maxillary in 7 cases, mandibular in 5 cases, and bimaxillary in 4 cases. The treatment consisted of parathyroidectomy in 13 patients, maxillary resection in 3 cases, and vitamin D treatment in 2 cases. Favorable outcomes, characterized by tumor regression, were reported in 9 cases, whereas unfavorable evolution was observed among 7 patients.

Conclusion

Parathyroidectomy is the gold standard treatment for primary hyperparathyroidism. It resulted in a total regression in all our cases. Regarding secondary hyperparathyroidism, blood screening and chronic renal insufficiency follow-up are critically valuable to detect this condition at an early stage, hence increasing the success rate of brown tumor regression. Our secondary and tertiary hyperparathyroidism results were miscellaneous; although it is important to emphasize the importance of the chronic renal insufficiency management to ensure a success.

Clinical relevance

Brown tumors should be included in the differential diagnosis of giant cell lesions. Parathyroidectomy is usually sufficient to induce the total regression of the lesion in primary hyperparathyroidism cases. A more delicate approach is needed regarding secondary hyperparathyroidism. Meticulous control of chronic renal insufficiency is mandatory in addition to parathyroidectomy.

Cardiomyopathy in chronic kidney disease: clinical features, biomarkers and the contribution of murine models in understanding pathophysiology

The cardiorenal syndrome (CRS) is described as a multi-organ disease encompassing bidirectionally heart and kidney. In CRS type 4, chronic kidney disease (CKD) leads to cardiac injury. Different pathological mechanisms have been identified to contribute to the establishment of CKD-induced cardiomyopathy, including a neurohormonal dysregulation, disturbances in the mineral metabolism and an accumulation of uremic toxins, playing an important role in the development of inflammation and oxidative stress. Combined, this leads to cardiac dysfunction and cardiac pathophysiological and morphological changes, like left ventricular hypertrophy, myocardial fibrosis and cardiac electrical changes. Given that around 80% of dialysis patients suffer from uremic cardiomyopathy, the study of cardiac outcomes in CKD is clinically highly relevant. The present review summarizes clinical features and biomarkers of CKD-induced cardiomyopathy and discusses underlying pathophysiological mechanisms recently uncovered in the literature. It discloses how animal models have contributed to the understanding of pathological kidney-heart crosstalk, but also provides insights into the variability in observed effects of CKD on the heart in different CKD mouse models, covering both "single hit" as well as "multifactorial hit" models. Overall, this review aims to support research progress in the field of CKD-induced cardiomyopathy.

Comparison of the Oral Calcimimetics Evocalcet and Cinacalcet in East Asian Patients on Hemodialysis with Secondary Hyperparathyroidism

Introduction

Evocalcet is an oral calcimimetic agent with proven efficacy and safety in treating secondary hyperparathyroidism (SHPT) in Japanese patients on dialysis.

Methods

This randomized, double-blind, intrapatient dose-adjustment, parallel-group, international multicenter study compared the efficacy and safety of evocalcet versus cinacalcet for 52 weeks in East Asian hemodialysis patients with SHPT.

Results

In total, 203 and 200 patients were randomized to receive evocalcet or cinacalcet, respectively (overall, 70.1% had baseline intact parathyroid hormone (PTH) levels ≥500 pg/ml, with no between-group difference). Mean percentage changes in intact PTH levels from baseline were -34.7% and -30.2% in the evocalcet and cinacalcet groups at 52 weeks (between-group difference -4.4%, 95% confidence interval [CI] -13.1%, 4.3%, below the predefined 15% noninferiority margin). Overall, 67.3% and 58.7% of patients in the evocalcet and cinacalcet groups, respectively, achieved ≥30% decrease in intact PTH levels from baseline (between-group difference 8.6%; 95% CI -1.8%, 19.1%). No major safety concerns were observed. Gastrointestinal adverse events (AEs) were significantly less frequent with evocalcet compared with cinacalcet (33.5% vs. 50.5%, P = 0.001), whereas the incidence of hypocalcemia did not differ.

Conclusion

Evocalcet might be a better alternative to cinacalcet for East Asian patients on hemodialysis with SHPT.

Vascular calcification: from the perspective of crosstalk

Vascular calcification (VC) is highly correlated with cardiovascular disease morbidity and mortality, but anti-VC treatment remains an area to be tackled due to the ill-defined molecular mechanisms. Regardless of the type of VC, it does not depend on a single cell but involves multi-cells/organs to form a complex cellular communication network through the vascular microenvironment to participate in the occurrence and development of VC. Therefore, focusing only on the direct effect of pathological factors on vascular smooth muscle cells (VSMCs) tends to overlook the combined effect of other cells and VSMCs, including VSMCs-VSMCs, ECs-VMSCs, Macrophages-VSMCs, etc. Extracellular vesicles (EVs) are a collective term for tiny vesicles with a membrane structure that are actively secreted by cells, and almost all cells secrete EVs. EVs docked on the surface of receptor cells can directly mediate signal transduction or transfer their contents into the cell to elicit a functional response from the receptor cells. They have been proven to participate in the VC process and have also shown attractive therapeutic prospects. Based on the advantages of EVs and the ability to be detected in body fluids, they may become a novel therapeutic agent, drug delivery vehicle, diagnostic and prognostic biomarker, and potential therapeutic target in the future. This review focuses on the new insight into VC molecular mechanisms from the perspective of crosstalk, summarizes how multi-cells/organs interactions communicate via EVs to regulate VC and the emerging potential of EVs as therapeutic methods in VC. We also summarize preclinical experiments on crosstalk-based and the current state of clinical studies on VC-related measures.

Giant Pancreatic Pseudocyst after Coronary Artery Bypass Graft in a Hemodialysis Patient: A Case Report

End-stage renal disease (ESRD) patients have a high prevalence of coronary artery disease, and coronary artery bypass graft (CABG) is one of the essential treatments. ESRD patients undergoing CABG surgery have an increased risk of postoperative complications, including acute pancreatitis. Here, we present the unique case of an exceptionally large pancreatic pseudocyst caused by pancreatitis in an ESRD patient after CABG surgery. A 45-year-old male with ESRD under maintenance hemodialysis received CABG surgery for significant coronary artery disease. Two weeks later, he experienced worsening abdominal pain and a palpable mass was noticed in the epigastric region. Computer tomography revealed an unusually large pseudocyst measuring 21 × 17 cm in the retroperitoneum due to necrotizing pancreatitis. The patient underwent percutaneous cystic drainage, and the symptoms were significantly improved without surgical intervention. Factors such as prolonged cardiopulmonary bypass time, postoperative hypotension, and intradialytic hypotension appeared to have contributed to the development of severe pancreatitis in this case. This report highlights the rarity of a giant pancreatic pseudocyst in an ESRD patient after CABG surgery and emphasizes the importance of vigilant postoperative care.

Early diagnosis strategy of calciphylaxis in dialysis patients

Calciphylaxis, a rapidly progressive and potentially life-threatening vascular calcification syndrome that clinically presents with persistently painful, ulcerative, or necrotizing skin lesions in multiple parts of the body, is predominantly observed in patients treated with dialysis. Early diagnosis of calciphylaxis is a key measure for reducing high disability and mortality. At present, there is no unified diagnostic standard for calciphylaxis, and there is a lack of effective early screening strategies. This paper summarized and discussed the diagnostic accuracy of calciphylaxis based on the latest research worldwide. We propose a modified strategy for the early diagnosis of calciphylaxis, which is suitable for dialysis patients to help clinicians better identify such disease and improve prognosis.

Efficacy and Safety of Upacicalcet in Hemodialysis Patients with Secondary Hyperparathyroidism: A Randomized Placebo-Controlled Trial

BACKGROUND

Secondary hyperparathyroidism is a major complication of patients undergoing hemodialysis (HD). Upacicalcet, a new injectable calcimimetic, acts on calcium-sensing receptors to suppress parathyroid hormone (PTH) secretion. We examined the efficacy and safety of upacicalcet in patients with secondary hyperparathyroidism receiving HD.

METHODS

In this phase 3, double-blind, placebo-controlled study, we randomized Japanese patients undergoing HD with serum intact PTH (iPTH) concentrations >240 pg/ml and corrected calcium concentrations ≥8.4 mg/dl. Either upacicalcet or placebo was administered after each HD session for 24 weeks. The primary outcome was the percentage of participants achieving the target mean serum iPTH concentration (60-240 pg/ml) at weeks 22-24.

RESULTS

A total of 103 participants received upacicalcet, and 50 participants received the placebo. The percentage of participants achieving mean serum iPTH concentrations of 60-240 pg/ml during the evaluation period was 67% (69/103) in the upacicalcet group and 8% (4/50) in the placebo group. The difference between the two groups was 59% (95% confidence interval, 48% to 71%). Upacicalcet also decreased serum fibroblast growth factor-23, bone-specific alkaline phosphatase, total type 1 procollagen-N-propeptide, and tartrate-resistant acid phosphatase-5b concentrations. Adverse events were reported in 85% (88/103) and 72% (36/50) participants in the upacicalcet and placebo groups, respectively. The incidence of upper gastrointestinal adverse events, such as nausea and vomiting, was similar between the two groups. Serum corrected calcium concentrations <7.5 mg/dl were observed in 2% of participants in the upacicalcet group and no participants in the placebo group.

CONCLUSIONS

Upacicalcet, a novel injectable calcimimetic, is effective and safe for secondary hyperparathyroidism patients receiving HD.

CLINICAL TRIAL REGISTRY NAME AND REGISTRATION NUMBER

Phase 3 Study of SK-1403, NCT03801980 .

[Diagnosis and treatment of osteoporosis in patients with chronic kidney disease : Joint guidelines of the Austrian Society for Bone and Mineral Research (ÖGKM), the Austrian Society of Physical and Rehabilitation Medicine (ÖGPMR) and the Austrian Society of Nephrology (ÖGN)]

DEFINITION AND EPIDEMIOLOGY

Chronic kidney disease (CKD): abnormalities of kidney structure or function, present for over 3 months. Staging of CKD is based on GFR and albuminuria (not graded). Osteoporosis: compromised bone strength (low bone mass, disturbance of microarchitecture) predisposing to fracture. By definition, osteoporosis is diagnosed if the bone mineral density T‑score is ≤ -2.5. Furthermore, osteoporosis is diagnosed if a low-trauma (inadequate trauma) fracture occurs, irrespective of the measured T‑score (not graded). The prevalence of osteoporosis, osteoporotic fractures and CKD is increasing worldwide (not graded). PATHOPHYSIOLOGY, DIAGNOSIS AND TREATMENT OF CHRONIC KIDNEY DISEASE-MINERAL AND BONE DISORDER (CKD-MBD): Definition of CKD-MBD: a systemic disorder of mineral and bone metabolism due to CKD manifested by either one or a combination of the following: abnormalities of calcium, phosphorus, PTH, or vitamin D metabolism; renal osteodystrophy; vascular calcification (not graded). Increased, normal or decreased bone turnover can be found in renal osteodystrophy (not graded). Depending on CKD stage, routine monitoring of calcium, phosphorus, alkaline phosphatase, PTH and 25-OH-vitamin D is recommended (2C). Recommendations for treatment of CKD-MBD: Avoid hypercalcemia (1C). In cases of hyperphosphatemia, lower phosphorus towards normal range (2C). Keep PTH within or slightly above normal range (2D). Vitamin D deficiency should be avoided and treated when diagnosed (1C).

DIAGNOSIS AND RISK STRATIFICATION OF OSTEOPOROSIS IN CKD

Densitometry (using dual X‑ray absorptiometry, DXA): low T‑score correlates with increased fracture risk across all stages of CKD (not graded). A decrease of the T‑score by 1 unit approximately doubles the risk for osteoporotic fracture (not graded). A T-score ≥ -2.5 does not exclude osteoporosis (not graded). Bone mineral density of the lumbar spine measured by DXA can be increased and therefore should not be used for the diagnosis or monitoring of osteoporosis in the presence of aortic calcification, osteophytes or vertebral fracture (not graded). FRAX can be used to aid fracture risk estimation in all stages of CKD (1C). Bone turnover markers can be measured in individual cases to monitor treatment (2D). Bone biopsy may be considered in individual cases, especially in patients with CKD G5 (eGFR < 15 ml/min/1.73 m2) or CKD 5D (dialysis).

SPECIFIC TREATMENT OF OSTEOPOROSIS IN PATIENTS WITH CKD

Hypocalcemia should be treated and serum calcium normalized before initiating osteoporosis therapy (1C). CKD G1-G2 (eGFR ≥ 60 ml/min/1.73 m2): treat osteoporosis as recommended for the general population (1A). CKD G3-G5D (eGFR < 60 ml/min/1.73 m2 to dialysis): treat CKD-MBD first before initiating osteoporosis treatment (2C). CKD G3 (eGFR 30-59 ml/min/1.73 m2) with PTH within normal limits and osteoporotic fracture and/or high fracture risk according to FRAX: treat osteoporosis as recommended for the general population (2B). CKD G4-5 (eGFR < 30 ml/min/1.73 m2) with osteoporotic fracture (secondary prevention): Individualized treatment of osteoporosis is recommended (2C). CKD G4-5 (eGFR < 30 ml/min/1.73 m2) and high fracture risk (e.g. FRAX score > 20% for a major osteoporotic fracture or > 5% for hip fracture) but without prevalent osteoporotic fracture (primary prevention): treatment of osteoporosis may be considered and initiated individually (2D). CKD G4-5D (eGFR < 30 ml/min/1.73 m2 to dialysis): Calcium should be measured 1-2 weeks after initiation of antiresorptive therapy (1C).

PHYSICAL MEDICINE AND REHABILITATION

Resistance training prioritizing major muscle groups thrice weekly (1B). Aerobic exercise training for 40 min four times per week (1B). Coordination and balance exercises thrice weekly (1B). Flexibility exercise 3-7 times per week (1B).

Current and Emerging Markers and Tools Used in the Diagnosis and Management of Chronic Kidney Disease-Mineral and Bone Disorder in Non-Dialysis Adult Patients

Chronic kidney disease (CKD) is a significant public health concern associated with significant morbidity and has become one of the foremost global causes of death in recent years. A frequent comorbidity of CKD is secondary hyperparathyroidism (SHPT), exemplified by high serum parathyroid hormone (PTH) levels. The mineral metabolism disturbances resulting from CKD and progression to SHPT are currently considered part of the definition of chronic kidney disease-mineral and bone disorder (CKD-MBD). However, CKD-MBD does not only include abnormalities in laboratory-measured parameters; it is a complex condition characterized by dysregulation of bone turnover, mineralization, growth and strength, accompanied by vascular or another soft-tissue calcification. Together, this increases the risk of bone fractures, cardiovascular disease, and overall mortality in CKD-MBD patients. Monitoring serum markers is essential in diagnosing SHPT and CKD-MBD, and there are several recognized indicators for prognosis, optimal clinical management and treatment response in late-stage kidney disease patients receiving dialysis. However, far fewer markers have been established for patients with non-dialysis CKD. This review provides an overview of current and emerging markers and tools used in the diagnosis and management of CKD-MBD in non-dialysis adult patients.

Progress in pharmacotherapy for the treatment of hyperphosphatemia in renal failure

INTRODUCTION

Among the clinical and metabolic complications of progressive chronic kidney disease (CKD), CKD-mineral bone disorder (CKD-MBD) significantly contributes to morbidity and mortality. While overt and persistent hyperphosphatemia is typical of advanced CKD and requires treatment, other abnormalities of calcium/phosphate metabolism begin to occur since the early stages of the disease.

AREAS COVERED

We searched on the PubMed database, without restrictions for language or time range, for randomized clinical trials and meta-analyses investigating phosphate-lowering therapies. The various phosphate binders show different safety profiles and diverse effects on calcium/phosphate metabolism and vascular calcification. The in-depth knowledge of the characteristics of these drugs is crucial to ensure adequate treatment to CKD patients.

EXPERT OPINION

A proper control of serum phosphate can be achieved using phosphate binders. These medications may induce side effects. Moreover, data on their impact on clinical outcomes are partly controversial or scarce, especially for the new generation drugs. Hyperphosphatemia favors cardiovascular disease and increases the risk for CKD progression. These effects are partially mediated by fibroblast growth factor 23 (FGF23), a phosphaturic hormone that raises to maintain normal serum phosphate. Since there are no data supporting the use of phosphate-lowering agents when phosphataemia is normal, a key role is played by reducing dietary phosphate intake with the aim to control serum phosphate and the compensatory FGF23 and parathyroid hormone (PTH) increase.

Identification of key biomarkers based on the proliferation of secondary hyperparathyroidism by bioinformatics analysis and machine learning

Objective

Secondary hyperparathyroidism (SHPT) is a frequent complication of chronic kidney disease (CKD) associated with morbidity and mortality. This study aims to identify potential biomarkers that may be used to predict the progression of SHPT and to elucidate the molecular mechanisms of SHPT pathogenesis at the transcriptome level.

Methods

We analyzed differentially expressed genes (DEGs) between diffuse and nodular parathyroid hyperplasia of SHPT patients from the GSE75886 dataset, and then verified DEG levels with the GSE83421 data file of primary hyperparathyroidism (PHPT) patients. Candidate gene sets were selected by machine learning screens of differential genes and immune cell infiltration was explored with the CIBERSORT algorithm. RcisTarget was used to predict transcription factors, and Cytoscape was used to construct a lncRNA-miRNA-mRNA network to identify possible molecular mechanisms. Immunohistochemistry (IHC) staining and quantitative real-time polymerase chain reaction (qRT-PCR) were used to verify the expression of screened genes in parathyroid tissues of SHPT patients and animal models.

Results

A total of 614 DEGs in GSE75886 were obtained as candidate gene sets for further analysis. Five key genes (USP12, CIDEA, PCOLCE2, CAPZA1, and ACCN2) had significant expression differences between groups and were screened with the best ranking in the machine learning process. These genes were shown to be closely related to immune cell infiltration levels and play important roles in the immune microenvironment. Transcription factor ZBTB6 was identified as the master regulator, alongside multiple other transcription factors. Combined with qPCR and IHC assay of hyperplastic parathyroid tissues from SHPT patients and rats confirm differential expression of USP12, CIDEA, PCOLCE2, CAPZA1, and ACCN2, suggesting that they may play important roles in the proliferation and progression of SHPT.

Conclusion

USP12, CIDEA, PCOLCE2, CAPZA1, and ACCN2 have great potential both as biomarkers and as therapeutic targets in the proliferation of SHPT. These findings suggest novel potential targets and future directions for SHPT research.

Salt-Sensitive Hypertension: Mediation by Salt-Induced Hypervolemia and Phosphate-Induced Vascular Calcification

Preventing hypertension by restricting dietary salt intake, sodium chloride, is well established in public health policy, but a pathophysiological mechanism has yet to explain the controversial clinical finding that some individuals have a greater risk of hypertension from exposure to salt intake, termed salt-sensitive hypertension. The present perspective paper synthesizes interdisciplinary findings from the research literature and offers novel insights proposing that the pathogenesis of salt-sensitive hypertension is mediated by interaction of salt-induced hypervolemia and phosphate-induced vascular calcification. Arterial stiffness and blood pressure increase as calcification in the vascular media layer reduces arterial elasticity, preventing arteries from expanding to accommodate extracellular fluid overload in hypervolemia related to salt intake. Furthermore, phosphate has been found to be a direct inducer of vascular calcification. Reduction of dietary phosphate may help reduce salt-sensitive hypertension by lowering the prevalence and progression of vascular calcification. Further research should investigate the correlation of vascular calcification with salt-sensitive hypertension, and public health recommendations to prevent hypertension should encourage reductions of both sodium-induced hypervolemia and phosphate-induced vascular calcification.

Pathophysiology of bone disease in chronic kidney disease: from basics to renal osteodystrophy and osteoporosis

Chronic kidney disease (CKD) is a highly prevalent disease that has become a public health problem. Progression of CKD is associated with serious complications, including the systemic CKD-mineral and bone disorder (CKD-MBD). Laboratory, bone and vascular abnormalities define this condition, and all have been independently related to cardiovascular disease and high mortality rates. The "old" cross-talk between kidney and bone (classically known as "renal osteodystrophies") has been recently expanded to the cardiovascular system, emphasizing the importance of the bone component of CKD-MBD. Moreover, a recently recognized higher susceptibility of patients with CKD to falls and bone fractures led to important paradigm changes in the new CKD-MBD guidelines. Evaluation of bone mineral density and the diagnosis of "osteoporosis" emerges in nephrology as a new possibility "if results will impact clinical decisions". Obviously, it is still reasonable to perform a bone biopsy if knowledge of the type of renal osteodystrophy will be clinically useful (low versus high turnover-bone disease). However, it is now considered that the inability to perform a bone biopsy may not justify withholding antiresorptive therapies to patients with high risk of fracture. This view adds to the effects of parathyroid hormone in CKD patients and the classical treatment of secondary hyperparathyroidism. The availability of new antiosteoporotic treatments bring the opportunity to come back to the basics, and the knowledge of new pathophysiological pathways [OPG/RANKL (LGR4); Wnt-ß-catenin pathway], also affected in CKD, offers great opportunities to further unravel the complex physiopathology of CKD-MBD and to improve outcomes.

The fibroblast growth factor system in cognitive disorders and dementia

Cognitive impairment is the core precursor to dementia and other cognitive disorders. Current hypotheses suggest that they share a common pathological basis, such as inflammation, restricted neurogenesis, neuroendocrine disorders, and the destruction of neurovascular units. Fibroblast growth factors (FGFs) are cell growth factors that play essential roles in various pathophysiological processes via paracrine or autocrine pathways. This system consists of FGFs and their receptors (FGFRs), which may hold tremendous potential to become a new biological marker in the diagnosis of dementia and other cognitive disorders, and serve as a potential target for drug development against dementia and cognitive function impairment. Here, we review the available evidence detailing the relevant pathways mediated by multiple FGFs and FGFRs, and recent studies examining their role in the pathogenesis and treatment of cognitive disorders and dementia.

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.

Can mean platelet volume predicts renal outcome in acute on chronic kidney disease?

INTRODUCTION

This study aimed to investigate the role of mean platelet volume (MPV) in predicting renal outcome in acute kidney injury (AKI) developing on pre-existing chronic kidney disease (CKD).

METHODS

The patients whose first hemodialysis program was initiated in our center were divided into two groups as those who were taken to the scheduled dialysis program after discharge and those who were not dialysis-dependent. Groups were compared in terms of demographic characteristics, and laboratory parameters including MPV.

RESULTS

A total of 288 patients were included in the study (scheduled dialysis = 162 patients, nondialysis dependent = 126 patients). High MPV was found to be an independent risk factor for scheduled dialysis programs in multivariable analyses (OR [95% CI]: 90.9 [6.3-1313.6], p: 0.001).

CONCLUSION

CKD patients with high MPV were more likely to be included in scheduled dialysis programs after an AKI attack. MPV is found to be an independent risk factor and a reliable predictor for a scheduled dialysis program.