Real-world usage of Chronic Kidney Disease - Mineral Bone Disorder (CKD-MBD) biomarkers in nephrology practices.

Background: Chronic kidney disease mineral bone disorder (CKD-MBD) is a condition characterized by alterations of calcium, phosphate, parathyroid hormone (PTH), and fibroblast growth factor 23 (FGF-23) metabolism that in turn promote bone disorders, vascular calcifications, and increase cardiovascular (CV) risk. Nephrologists' awareness of diagnostic, prognostic, and therapeutic tools to manage CKD-MBD plays a primary role in adequately preventing and managing this condition in clinical practice. Methods: A national survey (composed of 15 closed questions) was launched to inquire about the use of bone biomarkers in the management of CKD-MBD patients by nephrologists and to gain knowledge about the implementation of guideline recommendations in clinical practice. Results: One hundred and six Italian nephrologists participated in the survey for an overall response rate of about 10%. Nephrologists indicated that the laboratories of their hospitals were able to satisfy request of ionized calcium levels, 105 (99.1%) of both PTH and alkaline phosphatase (ALP), 100 (94.3%) of 25(OH)D, and 61 (57.5%) of 1.25(OH)2D; while most laboratories did not support the requests of biomarkers such as FGF-23 (intact: 88.7% and c-terminal: 93.4%), Klotho (95.3%; soluble form: 97.2%), tartrate-resistant acid phosphatase 5b (TRAP-5b) (92.5%), C-terminal telopeptide (CTX) (71.7%), and pro-collagen type 1 N-terminal pro-peptide (P1NP) (88.7%). As interesting data regarding Italian nephrologists' behavior to start treatment of secondary hyperparathyroidism (sHPT), the majority of clinicians used KDOQI guidelines (n = 55, 51.9%). In contrast, only 40 nephrologists (37.7%) relied on KDIGO guidelines, which recommended referring to values of PTH between two and nine times the upper limit of the normal range. Conclusion: Results point out a marked heterogeneity in the management of CKD-MBD by clinicians as well as a suboptimal implementation of guidelines in Italian clinical practice.

Effect of Antidiabetic Drugs on Bone Health in Patients with Normal Renal Function and in Chronic Kidney Disease (CKD): Insight into Clinical Challenges in the Treatment of Type 2 Diabetes.

Among the metabolic changes occurring during the course of type 2 diabetes (T2DM) and diabetic kidney disease (DKD), impaired bone health with consequent increased fracture risk is one of the most complex and multifactorial complications. In subjects with diabetic kidney disease, skeletal abnormalities may develop as a consequence of both conditions. In the attempt to define a holistic approach to diabetes, potential effects of various classes of antidiabetic drugs on the skeleton should be considered in the setting of normal kidney function and in DKD. We reviewed the main evidence on these specific topics. Experimental studies reported potential beneficial and harmful effects on bone by different antidiabetics, with few data available in DKD. Clinical studies specifically designed to evaluate skeletal effects of antidiabetics have not been performed; notwithstanding, data gleaned from randomized controlled trials and intervention studies did not completely confirm observations made by basic research. In the aggregate, evidence from meta-analyses of these studies suggests potential positive effects on fracture risk by metformin and glucagon-like peptide-1 receptor agonists, neutral effects by dipeptidyl peptidase-4 inhibitors, sodium-glucose cotransporter-2 inhibitors, and sulfonylureas, and negative effects by insulin and thiazolidinediones. As no clinical recommendations on the management of antidiabetic drugs currently include fracture risk assessment among the main goal of therapy, we propose an integrated approach with the aim of defining a patient-centered management of diabetes in chronic kidney disease (CKD) and non-CKD patients. Future clinical evidence on the skeletal effects of antidiabetics will help in optimizing the approach to a personalized and more effective therapy of diabetes.

Future treatment of vascular calcification in chronic kidney disease.

INTRODUCTION: Cardiovascular disease (CVD) is one of the global leading causes of morbidity and mortality in chronic kidney disease (CKD) patients. Vascular calcification (VC) is a major cause of CVD in this population and is the consequence of complex interactions between inhibitor and promoter factors leading to pathological deposition of calcium and phosphate in soft tissues. Different pathological landscapes are associated with the development of VC, such as endothelial dysfunction, oxidative stress, chronic inflammation, loss of mineralization inhibitors, release of calcifying extracellular vesicles (cEVs) and circulating calcifying cells. AREAS COVERED: In this review, we examined the literature and summarized the pathophysiology, biomarkers and focused on the treatments of VC. EXPERT OPINION: Even though there is no consensus regarding specific treatment options, we provide the currently available treatment strategies that focus on phosphate balance, correction of vitamin D and vitamin K deficiencies, avoidance of both extremes of bone turnover, normalizing calcium levels and reduction of inflammatory response and the potential and promising therapeutic approaches liketargeting cellular mechanisms of calcification (e.g. SNF472, TNAP inhibitors).Creating novel scores to detect in advance VC and implementing targeted therapies is crucial to treat them and improve the future management of these patients.

Artificial Intelligence-Based Hyper Accuracy Three-Dimensional (HA3D®) Models in Surgical Planning of Challenging Robotic Nephron-Sparing Surgery: A Case Report and Snapshot of the State-of-the-Art with Possible Future Implications.

Recently, 3D models (3DM) gained popularity in urology, especially in nephron-sparing interventions (NSI). Up to now, the application of artificial intelligence (AI) techniques alone does not allow us to obtain a 3DM adequate to plan a robot-assisted partial nephrectomy (RAPN). Integration of AI with computer vision algorithms seems promising as it allows to speed up the process. Herein, we present a 3DM realized with the integration of AI and a computer vision approach (CVA), displaying the utility of AI-based Hyper Accuracy Three-dimensional (HA3D®) models in preoperative planning and intraoperative decision-making process of challenging robotic NSI. A 54-year-old Caucasian female with no past medical history was referred to the urologist for incidental detection of the right renal mass. Preoperative contrast-enhanced abdominal CT confirmed a 35 × 25 mm lesion on the anterior surface of the upper pole (PADUA 7), with no signs of distant metastasis. CT images in DICOM format were processed to obtain a HA3D® model. RAPN was performed using Da Vinci Xi surgical system in a three-arm configuration. The enucleation strategy was achieved after selective clamping of the tumor-feeding artery. Overall operative time was 85 min (14 min of warm ischemia time). No intra-, peri- and post-operative complications were recorded. Histopathological examination revealed a ccRCC (stage pT1aNxMx). AI is breaking new ground in medical image analysis panorama, with enormous potential in organ/tissue classification and segmentation, thus obtaining 3DM automatically and repetitively. Realized with the integration of AI and CVA, the results of our 3DM were accurate as demonstrated during NSI, proving the potentialities of this approach for HA3D® models' reconstruction.

Three-dimensional imaging reconstruction and laparoscopic robotic surgery: a winning combination for a complex case of multiple myomectomy.

OBJECTIVE: To demonstrate the intraoperative use of three-dimensional (3D) imaging reconstruction for a complex case of multiple myomectomy assigned to robot-assisted laparoscopic surgery. DESIGN: Stepwise demonstration of the technique with narrated video footage. SETTING: University tertiary care hospital. PATIENT(S): A 36-year-old nulliparous infertile woman with multiple uterine myomas (>20) presented with menorrhagia and pelvic discomfort for many months. Because of the huge number of fibroids present, the patient was considered eligible for laparoscopic robotic-assisted myomectomy. INTERVENTION(S): A robotic-assisted laparoscopic myomectomy was performed with the use of intraoperative 3D imaging reconstruction. After opening the retroperitoneum through the adnexal triangle and identifying the ureters, to reduce intraoperative bleeding, bulldog clamps were used to temporarily reduce uterine vascularization. A multiple myomectomy was then performed with the use of tenaculum and Maryland bipolar forceps. During the intervention, the surgeon used the 3D uterine reconstruction to adapt its surgical strategy. Multilayer running closure was achieved using a bidirectional barbed suture ensuring introflexion of the serosa. Patients' consent was obtained for publication of the case; institutional review board approval was not required for this case report as per our institution's policy. MAIN OUTCOME MEASURE(S): Description of a robotic-assisted myomectomy with the intraoperative use of 3D imaging reconstruction. RESULT(S): The total operative time was 105 minutes. A total of 21 fibroids were removed with 150 mL of intraoperative blood loss. The patient was discharged the day after. CONCLUSION(S): The application of 3D imaging technology could overcome one of the limitations of robot-assisted minimally invasive surgery, the lack of haptic feedback, enabling the surgeon to rapidly locate myomas and guide the intraoperative plan to optimize the results. Additional studies evaluating the clinical impact of this technique and its improvement are required.

Real-World Analysis of Outcomes and Economic Burden in Patients with Chronic Kidney Disease with and without Secondary Hyperparathyroidism among a Sample of the Italian Population.

This real-world analysis evaluated the clinical and economic burden of non-dialysis-dependent CKD patients with and without secondary hyperparathyroidism (sHPT) in Italy. An observational retrospective study was conducted using administrative databases containing a pool of healthcare entities covering 2.45 million health-assisted individuals. Adult patients with hospitalization discharge diagnoses for CKD stages 3, 4, and 5 were included from 1 January 2012 to 31 March 2015 and stratified using the presence/absence of sHPT. Of the 5710 patients, 3119 were CKD-only (62%) and 1915 were CKD + sHPT (38%). The groups were balanced using Propensity Score Matching (PSM). Kaplan-Meier curves revealed that progression to dialysis and cumulative mortality had a higher incidence in the CKD + sHPT versus CKD-only group in CKD stage 3 patients and the overall population. The total direct healthcare costs/patient at one-year follow-up were significantly higher in CKD + sHPT versus CKD-only patients (EUR 8593 vs. EUR 5671, p < 0.001), mostly burdened by expenses for drugs (EUR 2250 vs. EUR 1537, p < 0.001), hospitalizations (EUR 4628 vs. EUR 3479, p < 0.001), and outpatient services (EUR 1715 vs. EUR 654, p < 0.001). These findings suggest that sHPT, even at an early CKD stage, results in faster progression to dialysis, increased mortality, and higher healthcare expenditures, thus indicating that timely intervention can ameliorate the management of CKD patients affected by sHPT.

Double glomerulopathies or two-faced janus? A challenging case in the COVID-19 era.

SARS-CoV-2 very often causes kidney involvement through various mechanisms including: acute tubular injury, virus cell invasion, vascular damage due to hypercoagulability and finally dysregulation of the immune system. Even though there are no pathognomonic morphologic features that can rule out or confirm direct damage by SARS-CoV-2, the latest literature suggests that there may be some association. SARS-CoV-2 infection represents a poor prognostic factor, regardless of pulmonary involvement. We report a challenging case with complex renal biopsy findings suggestive of collapsing glomerulopathy and focal proliferative IgA-dominant glomerulonephritis in a patient affected by active hepatitis C virus (HCV), SARS-CoV-2 infection and personal history of cocaine abuse.

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.

Erratum to: A roadmap to parathyroidectomy for kidney transplant candidates.

[This corrects the article DOI: 10.1093/ckj/sfac050.].

Alkaline Phosphatase: An Old Friend as Treatment Target for Cardiovascular and Mineral Bone Disorders in Chronic Kidney Disease.

Alkaline phosphatase (ALP) is an evolutionary conserved enzyme and widely used biomarker in clinical practice. Tissue-nonspecific alkaline phosphatase (TNALP) is one of four human isozymes that are expressed as distinct TNALP isoforms after posttranslational modifications, mainly in bone, liver, and kidney tissues. Beyond the well-known effects on bone mineralization, the bone ALP (BALP) isoforms (B/I, B1, B1x, and B2) are also involved in the pathogenesis of ectopic calcification. This narrative review summarizes the recent clinical investigations and mechanisms that link ALP and BALP to inflammation, metabolic syndrome, vascular calcification, endothelial dysfunction, fibrosis, cardiovascular disease, and mortality. The association between ALP, vitamin K, bone metabolism, and fracture risk in patients with chronic kidney disease (CKD) is also discussed. Recent advances in different pharmacological strategies are highlighted, with the potential to modulate the expression of ALP directly and indirectly in CKD-mineral and bone disorder (CKD-MBD), e.g., epigenetic modulation, phosphate binders, calcimimetics, vitamin D, and other anti-fracture treatments. We conclude that the significant evidence for ALP as a pathogenic factor and risk marker in CKD-MBD supports the inclusion of concrete treatment targets for ALP in clinical guidelines. While a target value below 120 U/L is associated with improved survival, further experimental and clinical research should explore interventional strategies with optimal risk-benefit profiles. The future holds great promise for novel drug therapies modulating ALP.

An update on tenapanor to treat hyperphosphatemia.

Hyperphosphatemia is a common feature in patients with chronic kidney disease (CKD), especially in those with end-stage renal disease (ESRD). Commonly, high serum phosphate levels are observed only in later stages of CKD. The control of hyperphosphatemia plays a key role in the management of CKD patients. However, the optimal range for serum phosphate levels in CKD patients is still controversial. Currently, phosphate binders are the only medications available to reduce elevated serum phosphate levels in patients with ESRD receiving hemodialysis. Tenapanor, an inhibitor of gastrointestinal sodium/hydrogen exchanger 3 (NHE3), acts via a non-phosphate-binding mechanism, reducing paracellular phosphate transport in the intestine. Has tenapanor the potential to improve management of mineral bone disorder in CKD?

Denosumab-Induced Hypocalcemia and Hyperparathyroidism in de novo Kidney Transplant Recipients.

INTRODUCTION: Denosumab represents a realistic treatment option to increase bone mineral density in kidney transplant recipients (KTRs). It is still unknown how and at what extent posttransplantation bone disease and graft function influence the effects of denosumab on mineral metabolism indexes. In this study, we analyze risk factors of hypocalcemia and parathyroid hormone (PTH) increase after denosumab administration in eighteen de novo KTRs and its management before and after this treatment. METHODS: We conducted a monocentric, observational, prospective study on de novo KTRs. All KTRs enrolled received a single 60 mg subcutaneous dose of denosumab every 6 months. Before kidney transplantation, no patients were treated with calcio-mimetic. After kidney transplantation and before antiresorptive therapy, no patients were treated with calcio-mimetic drugs and/or vitamin D receptor agonists, while all patients received nutritional vitamin D supplementation (from 1,000 IU to 1,500 IU daily). RESULTS: Hypocalcemia was related to the degree of lumbar osteoporosis (p = 0.047); the increase in the PTH level was correlated to baseline bone turnover markers (bone alkaline phosphatase, serum osteocalcin, and ß-C-terminal telopeptide), the 25 OH status, and eGFR. The introduction of calcitriol, after the PTH increase, in addition to cholecalciferol was necessary to ensure an adequate control of serum calcium and PTH during a follow-up of 15 months. Following the treatment with denosumab, it was observed an improvement of areal bone mineral density both at lumbar and femoral sites with a mean percentual increase of 1.74% and 0.25%, respectively. CONCLUSIONS: Denosumab is an effective treatment for bone disease in KTRs. In our study, the increase in PTH is not a transient event but prolonged throughout the follow-up period and requires continuous supplementation therapy with calcitriol.

Vitamin D Effects on Bone Homeostasis and Cardiovascular System in Patients with Chronic Kidney Disease and Renal Transplant Recipients.

Poor vitamin D status is common in patients with impaired renal function and represents one main component of the complex scenario of chronic kidney disease-mineral and bone disorder (CKD-MBD). Therapeutic and dietary efforts to limit the consequences of uremia-associated vitamin D deficiency are a current hot topic for researchers and clinicians in the nephrology area. Evidence indicates that the low levels of vitamin D in patients with CKD stage above 4 (GFR < 15 mL/min) have a multifactorial origin, mainly related to uremic malnutrition, namely impaired gastrointestinal absorption, dietary restrictions (low-protein and low-phosphate diets), and proteinuria. This condition is further worsened by the compromised response of CKD patients to high-dose cholecalciferol supplementation due to the defective activation of renal hydroxylation of vitamin D. Currently, the literature lacks large and interventional studies on the so-called non-calcemic activities of vitamin D and, above all, the modulation of renal and cardiovascular functions and immune response. Here, we review the current state of the art of the benefits of supplementation with native vitamin D in various clinical settings of nephrological interest: CKD, dialysis, and renal transplant, with a special focus on the effects on bone homeostasis and cardiovascular outcomes.

Technical aspects to maximize the hyperaccuracy three-dimensional (HA3D™) computed tomography reconstruction for kidney stones surgery: a pilot study.

The aim of the current prospective pilot study was to describe a hyperaccuracy three-dimensional (HA3D™) model reconstruction technique, specifically developed to maximize the visualization of the renal collecting system's anatomy, and its relationship with the stones, vessels and renal parenchyma, and to compare the HA3D™ virtual models with the intraoperative findings. The image acquisition was performed using a CT scanner (Toshiba, Aquilion Prime) and included the unenhanced, arterial, venous and excretory phases. The DICOM format CT images were processed by MEDICS Srl ( www.medics3d.com , Turin, Italy). In total, study included three patients with renal stone scheduled for non-papillary prone percutaneous nephrolithotomy (PCNL). The median age and BMI were 51 (range 49-54) and 25.5 (range 25.0-32.7), respectively. The median stone size was 1170 mm2 (range 830-1520) and median stone density was 1130 HU (range 600-1340). In all cases, the quality of the CT images acquired with our protocol was adequate to perform the HA3D™ reconstruction. Median operative and puncture time were 39.4 (range 35.2-44.0) and 1.9 (range 1.8-2.1) mins, respectively. The success rate for the first attempt of the percutaneous puncture was 100%, and only one PCNL tract was sufficient to complete the surgery. All three patients were stone-free on the third postoperative day. A dedicated imaging acquisition protocol and a tailored 3D model reconstruction process specifically developed for kidney stones treatment allow obtaining HA3D™ highly relevant models to greatly match intraoperative findings during PCNL with the potential of minimizing bleeding and organ injury complications.

Renal dysfunction in psoriatic patients.

Psoriasis is a common chronic inflammatory disease of the skin that is increasingly being considered as a systemic inflammatory disorder due to its association with cardiovascular, metabolic, pulmonary, renal, liver, and neurologic diseases. Renal involvement is rare but well documented and psoriasis is recognized as an independent factor for CKD and ESKD. A careful monitoring of the urinalysis and of renal function is recommended in psoriatic patients, especially those with moderate-to-severe disease. In case of pathologic findings, the execution of a renal biopsy appears necessary to make an accurate diagnosis and to establish the most appropriate therapeutic strategies to prevent the progression of kidney damage. The mechanisms of kidney involvement are different and not yet fully clarified. We present here two case reports of renal dysfunction during psoriasis. In one case, we diagnosed IgA nephropathy with particularly severe clinical presentation; in the other, an advanced kidney injury due to nephrotoxicity after prolonged CNI treatment.