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Billa V, Zhong A, Bargman J, Vas S, Wong PY, Oreopoulos DG. High Prevalence of Hyperparathyroidism among Peritoneal Dialysis Patients: A Review of 176 Patients. Perit Dial Int 2020. [DOI: 10.1177/089686080002000308] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
ObjectivesParathyroid dysfunction continues to produce significant morbidity in dialysis patients. Since the introduction of low calcium dialysate for peritoneal dialysis (PD), no large studies have been done to determine the prevalence of parathyroid dysfunction in these patients. This study was done to assess the prevalence of parathyroid disease in the PD population and to determine the risk factors associated with this dysfunction.DesignWe analyzed data on 176 patients who received PD at a single center between August 1998 and February 1999. Clinical data, laboratory variables related to parathyroid function, and data pertaining to dialysis treatment and weekly drug dosing were obtained for each patient on two different occasions, approximately 3 months apart. Variables predictive of the development of parathyroid dysfunction were calculated by univariate and multivariate logistic regression analysis.ResultsTwo-thirds of the patients surveyed had an abnormal intact parathyroid hormone (iPTH) level: 47% had an iPTH level more than three times normal, the mean was 54.6 ± 35.4 pmol/L; 23% had an iPTH value below the upper limit of normal, here the mean was 3.6 ± 1.8 pmol/L. Diabetic patients had lower iPTH levels (22.2 ± 28.4 pmol/L) than nondiabetics (33.9 ± 34.8 pmol/L) ( p = 0.02). On multivariate regression analysis, we found that age, duration of dialysis, Kt/V, serum bicarbonate, and serum ionized calcium levels did not significantly affect parathyroid function. Hyperphosphatemia was the only factor that was associated with the development of secondary hyperparathyroidism in this study population ( p = 0.029).ConclusionThere is a high prevalence of hyperparathyroidism in the current PD population. Phosphate control is suboptimal and hyperphosphatemia is an independent risk factor for the development of hyperparathyroidism.
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Affiliation(s)
- Viswanath Billa
- Division of Nephrology, Department of Medicine, University Health Network, Toronto Western Division, University of Toronto, Toronto, Ontario, Canada
| | - Aimin Zhong
- Division of Nephrology, Department of Medicine, University Health Network, Toronto Western Division, University of Toronto, Toronto, Ontario, Canada
| | - Joanne Bargman
- Division of Nephrology, Department of Medicine, University Health Network, Toronto Western Division, University of Toronto, Toronto, Ontario, Canada
| | - Stephen Vas
- Division of Nephrology, Department of Medicine, University Health Network, Toronto Western Division, University of Toronto, Toronto, Ontario, Canada
| | - Pui Y. Wong
- Division of Nephrology, Department of Medicine, University Health Network, Toronto Western Division, University of Toronto, Toronto, Ontario, Canada
| | - Dimitrios G. Oreopoulos
- Division of Nephrology, Department of Medicine, University Health Network, Toronto Western Division, University of Toronto, Toronto, Ontario, Canada
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Prichard S, Sniderman A, Cianflone K, Marpole D. Cardiovascular Disease in Peritoneal Dialysis. Perit Dial Int 2020. [DOI: 10.1177/089686089601601s02] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Cardiovascular morbidity and mortality remain high in ESRD patients. Lipid abnormalities in CAPD may be more important than in hemodialysis. Vessel calcification may have a role in atherosclerotic heart disease, but this is only an inference from several clinical observations, and it remains to be defined more clearly as a risk factor. Left ventricular hypertrophy is frequent in this patient population, and is associated with specific clinical patterns and an in creased risk of death. Erythropoietin treatment of anemia and tight blood pressure controls have proved to help in reversing severe left ventricular hypertrophy. Finally, we describe a syndrome of the hypertrophic, high cardiac output hemodialysis heart, which is characterized by a high cardiac output in hemodialysis patients. It is associated with left ventricular hypertrophy and eventually right ventricular hypertrophy with tricuspid insufficiency. This may require fistula revision and even a switch to peritoneal dialysis.
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Affiliation(s)
- Sarah Prichard
- Divisions of Nephrology and Cardiology, Department of Medicine, Royal Victoria Hospital, McGi11 University, Montreal, Quebec, Canada
| | - Allan Sniderman
- Divisions of Nephrology and Cardiology, Department of Medicine, Royal Victoria Hospital, McGi11 University, Montreal, Quebec, Canada
| | - Katherine Cianflone
- Divisions of Nephrology and Cardiology, Department of Medicine, Royal Victoria Hospital, McGi11 University, Montreal, Quebec, Canada
| | - Derek Marpole
- Divisions of Nephrology and Cardiology, Department of Medicine, Royal Victoria Hospital, McGi11 University, Montreal, Quebec, Canada
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Dimkovic NB, Bargman J, Vas S, Oreopoulos DG. Normal or Low Initial PTH Levels are not a Predictor of Morbidity/Mortality in Patients Undergoing Chronic Peritoneal Dialysis. Perit Dial Int 2020. [DOI: 10.1177/089686080202200207] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
♦ Objective During the past few decades, the pattern of bone disease in uremic patients has changed significantly. There has been an increase in the number of patients with normal or low initial parathyroid hormone (PTH) levels, particularly in patients on chronic peritoneal dialysis (CPD). Previous authors have described a higher prevalence of bone pain, microfractures, and fractures, and higher mortality among these patients. The aim of this study was to determine the incidence, morbidity, and mortality of patients who had a low or normal intact PTH (iPTH) level when they started CPD. ♦ Design We reviewed the records of 251 patients in our program that started CPD during the past 5 years (January 1996 – December 2000). Clinical data, laboratory variables, medication, and dialysis parameters/dose were available at every clinic visit (approximately every 4 weeks). Intact PTH was used to express parathyroid function; values 3 times higher than the upper limit of normal (ULN) were assumed to be optimal. Variables predictive of the development of parathyroid dysfunction were calculated by univariate and multivariate logistic regression analysis. ♦ Results Of the patients who started CPD, 15.5% had iPTH values below the ULN (7.6 pmol/L), and an additional 29.5% had an iPTH of less than 3 times the ULN ( i.e., between 7.6 and 22.8 pmol/L). We call these two groups of patients the normal/low initial iPTH group. During the follow-up period (3 – 63 months), we found a trend toward increasing iPTH levels. By the end of the study period, 61.2% of those with normal/low initial iPTH remained in the normal/low iPTH range, and 38.8% had converted to a group with an iPTH range higher than 22.8 pmol/L. The patients who converted their iPTH grouping were younger, fewer of them were diabetics ( p = not significant), and they were more frequently on low calcium dialysate ( p < 0.05). Hyperphosphatemia was an independent risk factor for subsequent iPTH changes during the course of continuous ambulatory PD treatment. All patients in the normal/low iPTH groups had a low prevalence of bone fractures (3.5%). Also, patients who remained in the normal/low iPTH group at the end of the follow-up period did not have more fractures than those who converted to the hyperparathyroid group (3.8% vs 3.1%). We found no differences in bone fractures between patients with iPTH levels below 22.8 and those with levels above 22.8 pmol/L (3.5% vs 5.4%), nor were there differences in patient and technique survival between these two groups. ♦ Conclusion Normal/low initial iPTH is a frequent finding among patients starting CPD. Serum phosphorus was an independent risk factor for subsequent iPTH changes during the course of CPD treatment. Use of low calcium dialysate was significantly higher in patients who converted their iPTH into the high iPTH range. Very few patients with low/normal iPTH had bone-related symptoms (pain and fractures), and their morbidity and mortality did not differ from those patients with a high initial iPTH level.
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Affiliation(s)
- Nada B. Dimkovic
- Peritoneal Dialysis Program, Toronto Western Hospital, and Division of Nephrology, University Health Network, University of Toronto, Toronto, Ontario, Canada
| | - Joanne Bargman
- Peritoneal Dialysis Program, Toronto Western Hospital, and Division of Nephrology, University Health Network, University of Toronto, Toronto, Ontario, Canada
| | - Stephen Vas
- Peritoneal Dialysis Program, Toronto Western Hospital, and Division of Nephrology, University Health Network, University of Toronto, Toronto, Ontario, Canada
| | - Dimitrios G. Oreopoulos
- Peritoneal Dialysis Program, Toronto Western Hospital, and Division of Nephrology, University Health Network, University of Toronto, Toronto, Ontario, Canada
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Saha HH, Ala-Houhala IO, Liukko-Sipi SH, Ylitalo P, Pasternack AI. Pharmacokinetics of Clodronate in Peritoneal Dialysis Patients. Perit Dial Int 2020. [DOI: 10.1177/089686089801800210] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Objective To study the pharmacokinetics of clodronate in patients on continuous ambulatory peritoneal dialysis (CAPD). Design A single intravenous dose pharmacokinetic study. Setting University hospital. Patients Ten CAPD patients (3 female, 7 male, age 39 79 year, median 55). Methods Clodronate disodium in serum, urine, and dialysate was collected for 24 hours and analyzed by capillary gas chromatography with mass-selective detection. Results Only 7% of the infused dose of clodronate was eliminated through peritoneal dialysis during 24 hours. Clearance via CAPD (CLCAPD) was 2.4 ± 0.6 mL/min, which was less than 10% of the total serum clearance (CLtot’ 26.0 ± 19.3 mL/min). Even the kidneys were a more important route of elimination than CAPD in those patients with residual diuresis of more than 500 mL/24 hr. However, in all patients most of the clodronate serum clearance (77% ± 13%) took place via routes other than peritoneal dialysis or kidneys, that is, via nonrenal-non-CAPD clearance (CLNRD). CLNRD most likely represents the part of the drug deposited in the skeleton. There was a positive correlation between CLNRD and the plasma intact parathyroid hormone concentration. Conclusions CAPD removed clodronate poorly from the circulation. Most clearance took place via routes other than CAPD or kidneys. This CLNRD most likely represents the skeletal deposition of the drug, and this is related to the severity of hyperparathyroidism. When treating CAPD patients with hyperparathyroid bone disease, the administration of clodronate should be adjusted as in those subjects with severe renal failure.
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Affiliation(s)
- Heikki H.T. Saha
- University of Tampere, Medical School, Turku, Finland
- Tampere University Hospital, Tampere, Turku, Finland
| | | | | | - Pauli Ylitalo
- University of Tampere, Medical School, Turku, Finland
- Tampere University Hospital, Tampere, Turku, Finland
| | - Amos I. Pasternack
- University of Tampere, Medical School, Turku, Finland
- Tampere University Hospital, Tampere, Turku, Finland
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Wei M, Esbaei K, Bargman J, Oreopoulos DG. Relationship between Serum Magnesium, Parathyroid Hormone, and Vascular Calcification in Patients on Dialysis: A Literature Review. Perit Dial Int 2020. [DOI: 10.1177/089686080602600315] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Secondary hyperparathyroidism is present in most patients with end-stage renal disease and has been linked to uremic bone disease, vascular calcification, and mortality. Current literature suggests an association between hypomagnesemia and cardiovascular disease in the general population. We reviewed all published studies on the relationship between serum magnesium and parathyroid hormone and the relationship between serum Mg and vascular calcification in dialysis patients. Of these, 10 of 12 studies of patients on hemodialysis and 4 of 5 studies of patients on peritoneal dialysis showed a significant inverse relationship between serum Mg and serum intact parathyroid hormone. Hyperparathyroidism develops in peritoneal dialysis patients dialyzed with a solution containing normal calcium (1.25 mmol/L) and low Mg (0.25 mmol/L), even though serum calcium is maintained at a normal level. Four of the hemodialysis studies and one of the peritoneal dialysis studies indicated that there is an inverse relationship between serum Mg and vascular calcification in these patients. Potential benefits have been attributed to magnesium carbonate as a phosphate binder and it may possibly be an effective, less toxic, less expensive phosphate binder. We believe that the role of Mg in secondary hyperparathyroidism and vascular calcification merits further investigation.
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Affiliation(s)
- Mingxin Wei
- Home Peritoneal Dialysis Unit, University Health Network and University of Toronto, Toronto, Ontario, Canada
- Department of Nephrology, Guangxi People's Hospital, Guangxi, P. R. China
| | - Khaled Esbaei
- Home Peritoneal Dialysis Unit, University Health Network and University of Toronto, Toronto, Ontario, Canada
- Al-Fatah University, Tripoli Central Hospital, Tripoli, Libya
| | - Joanne Bargman
- Home Peritoneal Dialysis Unit, University Health Network and University of Toronto, Toronto, Ontario, Canada
| | - Dimitrios G. Oreopoulos
- Home Peritoneal Dialysis Unit, University Health Network and University of Toronto, Toronto, Ontario, Canada
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Sánchez-González C, Gonzalez-Casaus ML, Sellares VL, Albalate M, Torregrosa JV, Mas S, Ortiz A, Rodriguez M, Gonzalez-Parra E. Higher Proportion of Non-1-84 PTH Fragments in Peritoneal Dialysis Patients Compared to Hemodialysis Patients Using Solutions Containing 1.75 mmol/l Calcium. Front Physiol 2018; 9:1643. [PMID: 30524306 PMCID: PMC6262178 DOI: 10.3389/fphys.2018.01643] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2018] [Accepted: 10/30/2018] [Indexed: 11/13/2022] Open
Abstract
Background: The prevalence of low- turnover bone disease (LTBD) in peritoneal dialysis (PD) patients is higher than in hemodialysis (HD) patients. LTBD patients may be at risk for vascular calcification, and cardiovascular disease. Current therapy for chronic kidney disease metabolic bone disorders (CKD-MBD) is guided by biochemical parameters, as bone biopsy is not used in routine clinical care. Methods: We assessed intact PTH (iPTH: 1-84PTH plus non-1-84PTH), 1-84PTH, and the 1-84PTH/non-1-84PTH ratio in 129 hemodialysis and 73 PD prevalent patients dialyzed with solutions containing 1.75 mmol/L calcium. Results: Hemodialysis and PD patients presented similar iPTH and tCa values and prevalence of putative LTBD as defined according to KDOQI iPTH cut-off levels or 1-84 PTH levels. However, iCa accounted for a higher percentage of tCa in PD (53%) than in hemodialysis (39%) p < 0.001, and the 1-84PTH/non-1-84PTH ratio was lower in PD than in hemodialysis patients (0.44 ± 0.12) vs. (0.60 ± 0.10), p < 0.001. The prevalence of putative LTBD when using the coexistence of 1-84PTH/non-1-84PTH ratio < 1.0 and iPTH < 420 pg/m, was higher in PD than in hemodialysis patients (73 vs. 16% respectively, p < 0.001). In a multivariate logistic regression analysis, dialysis modality was the main determinant of the 1-84PTH/non-1-84PTH ratio. Conclusion: Solutions containing 1.75 mmol/L calciums are associated to a higher proportion of non-1-84PTH fragments in PD than in HD patients. Different analytical criteria result in widely different estimates of LTBD prevalence, thus impairing the ability of clinicians to optimize therapy for CKD-MBD.
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Affiliation(s)
| | | | | | | | | | - Sebastian Mas
- Unidad de Diálsis IIS Fundación Jiménez Díaz, School of Medicine, Universidad Autónoma de Madrid, Madrid, Spain
| | - Alberto Ortiz
- REDINREN, Madrid, Spain
- Unidad de Diálsis IIS Fundación Jiménez Díaz, School of Medicine, Universidad Autónoma de Madrid, Madrid, Spain
| | - Mariano Rodriguez
- REDINREN, Madrid, Spain
- Nefrología y Unidad de Investigación, Hospital Universitario Reina Sofia, Córdoba, Spain
| | - Emilio Gonzalez-Parra
- REDINREN, Madrid, Spain
- Unidad de Diálsis IIS Fundación Jiménez Díaz, School of Medicine, Universidad Autónoma de Madrid, Madrid, Spain
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Couttenye MM, D'Haese PC, De Broe ME. What Considerations Should we Give to Adynamic Bone Disease? Int J Artif Organs 2018. [DOI: 10.1177/039139889802101102] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
- M. M. Couttenye
- Department of Nephrology-Hypertension, University of Antwerp - Belgium
| | - P. C. D'Haese
- Department of Nephrology-Hypertension, University of Antwerp - Belgium
| | - M. E. De Broe
- Department of Nephrology-Hypertension, University of Antwerp - Belgium
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Morrone LF, Bolasco P, Camerini C, Cianciolo G, Cupisti A, Galassi A, Mazzaferro S, Russo D, Russo L, Cozzolino M. Vitamin D in patients with chronic kidney disease: a position statement of the Working Group "Trace Elements and Mineral Metabolism" of the Italian Society of Nephrology. J Nephrol 2016; 29:305-328. [PMID: 27062486 DOI: 10.1007/s40620-016-0305-6] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2016] [Accepted: 03/30/2016] [Indexed: 02/07/2023]
Abstract
In the late 1970s, calcitriol was introduced into clinical practice for the management of secondary renal hyperparathyroidism in chronic kidney disease (CKD). Since then, the use of calcifediol or other native forms of vitamin D was largely ignored until the publication of the 2009 Kidney Disease Improving Global Outcomes (KDIGO) recommendations. The guidelines suggested that measurement of circulating levels of 25(OH)D (calcifediol) and its supplementation were to be performed on the same basis as for the general population. This indication was based on the fact that the precursors of active vitamin D had provided to CKD patients considerable benefits in survival, mainly due to their pleiotropic effects on the cardiovascular system. However, despite the long-term use of various classes of vitamin D in CKD, a clear definition is still lacking concerning the most appropriate time for initiation of therapy, the best compound to prescribe (active metabolites or analogs), the proper dosage, and the most suitable duration of therapy. The aim of this position statement is to provide and critically appraise the current plentiful evidence on vitamin D in different clinical settings related to CKD, particularly focusing on outcomes, monitoring and treatment-associated risks. However, it should be taken in account that position statements are meant to provide guidance; therefore, they are not to be considered prescriptive for all patients and, importantly, they cannot replace the judgment of clinicians.
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Affiliation(s)
- Luigi Francesco Morrone
- Nephrology, Dialysis and Renal Transplantation Unit, University Hospital "Policlinico", Bari, Italy.
| | - Pergiorgio Bolasco
- Territorial Unit of Nephrology and Dialysis-ASL 8 of Cagliari, Cagliari, Italy
| | - Corrado Camerini
- Operative Unit of Nephrology, AO Spedali Civili di Brescia and University of Brescia, Brescia, Italy
| | - Giuseppe Cianciolo
- Nephrology Dialysis and Renal Transplantation Unit, S. Orsola University Hospital, Bologna, Italy
| | - Adamasco Cupisti
- Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy
| | | | - Sandro Mazzaferro
- Department of Cardiovascular Respiratory Nephrologic Anesthetic and Geriatric Sciences, Sapienza University of Rome, Rome, Italy
| | - Domenico Russo
- Department of Public Health, Unit of Nephrology and Hypertension, University of Naples Federico II, Naples, Italy
| | - Luigi Russo
- Department of Public Health, Unit of Nephrology and Hypertension, University of Naples Federico II, Naples, Italy
| | - Mario Cozzolino
- Renal Division and Laboratory of Experimental Nephrology, Department of Health Sciences, San Paolo Hospital, University of Milan, Milan, Italy
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Tamminen IS, Valta H, Jalanko H, Salminen S, Mäyränpää MK, Isaksson H, Kröger H, Mäkitie O. Pediatric solid organ transplantation and osteoporosis: a descriptive study on bone histomorphometric findings. Pediatr Nephrol 2014; 29:1431-40. [PMID: 24562785 DOI: 10.1007/s00467-014-2771-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/23/2013] [Revised: 01/15/2014] [Accepted: 01/22/2014] [Indexed: 01/08/2023]
Abstract
BACKGROUND Organ transplantation may lead to secondary osteoporosis in children. This study characterized bone histomorphometric findings in pediatric solid organ transplant recipients who were assessed for suspected secondary osteoporosis. METHODS Iliac crest biopsies were obtained from 19 children (7.6-18.8 years, 11 male) who had undergone kidney (n = 6), liver (n = 9), or heart (n = 4) transplantation a median 4.6 years (range 0.6-16.3 years) earlier. All patients had received oral glucocorticoids at the time of the biopsy. RESULTS Of the 19 patients, 21 % had sustained peripheral fractures and 58 % vertebral compression fractures. Nine children (47 %) had a lumbar spine BMD Z-score below -2.0. Histomorphometric analyses showed low trabecular bone volume (< -1.0 SD) in 6 children (32 %) and decreased trabecular thickness in 14 children (74 %). Seven children (37 %) had high bone turnover at biopsy, and low turnover was found in 6 children (32 %), 1 of whom had adynamic bone disease. CONCLUSIONS There was a great heterogeneity in the histological findings in different transplant groups, and the results were unpredictable using non-invasive methods. The observed changes in bone quality (i.e. abnormal turnover rate, thin trabeculae) rather than the actual loss of trabecular bone, might explain the increased fracture risk in pediatric solid organ transplant recipients.
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Affiliation(s)
- Inari S Tamminen
- Bone and Cartilage Research Unit (BCRU), University of Eastern Finland, POB 1627, Mediteknia Building, 70211, Kuopio, Finland,
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Sangvanich T, Ngamcherdtrakul W, Lee R, Morry J, Castro D, Fryxell GE, Yantasee W. Nanoporous sorbent material as an oral phosphate binder and for aqueous phosphate, chromate, and arsenate removal. ACTA ACUST UNITED AC 2014; 5. [PMID: 25554735 DOI: 10.4172/2157-7439.1000222] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Phosphate removal is both biologically and environmentally important. Biologically, hyperphosphatemia is a critical condition in end-stage chronic kidney disease patients. Patients with hyperphosphatemia are treated long-term with oral phosphate binders to prevent phosphate absorption to the body by capturing phosphate in the gastrointestinal (GI) tract followed by fecal excretion. Environmentally, phosphate levels in natural water resources must be regulated according to limits set forth by the US Environmental Protection Agency. By utilizing nanotechnology and ligand design, we developed a new material to overcome limitations of traditional sorbent materials such as low phosphate binding capacity, slow binding kinetics, and negative interference by other anions. A phosphate binder based on iron-ethylenediamine on nanoporous silica (Fe-EDA-SAMMS) has been optimized for substrates and Fe(III) deposition methods. The Fe-EDA-SAMMS material had a 4-fold increase in phosphate binding capacity and a broader operating pH window compared to other reports. The material had a faster phosphate binding rate and was significantly less affected by other anions than Sevelamer HCl, the gold standard oral phosphate binder, and AG® 1-X8, a commercially available anion exchanger. It had less cytotoxicity to Caco-2 cells than lanthanum carbonate, another prescribed oral phosphate binder. The Fe-EDA-SAMMS also had high capacity for arsenate and chromate, two of the most toxic anions in natural water.
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Affiliation(s)
- Thanapon Sangvanich
- Department of Biomedical Engineering, Oregon Health & Science University (OHSU), Portland, Oregon, USA
| | - Worapol Ngamcherdtrakul
- Department of Biomedical Engineering, Oregon Health & Science University (OHSU), Portland, Oregon, USA
| | - Richard Lee
- Department of Biomedical Engineering, Oregon Health & Science University (OHSU), Portland, Oregon, USA
| | - Jingga Morry
- Department of Biomedical Engineering, Oregon Health & Science University (OHSU), Portland, Oregon, USA
| | - David Castro
- Department of Biomedical Engineering, Oregon Health & Science University (OHSU), Portland, Oregon, USA ; PDX Pharmaceuticals, LLC, Lake Oswego, Oregon
| | - Glen E Fryxell
- Battelle Distinguished Inventor, Kennewick, Washington, USA
| | - Wassana Yantasee
- Department of Biomedical Engineering, Oregon Health & Science University (OHSU), Portland, Oregon, USA ; PDX Pharmaceuticals, LLC, Lake Oswego, Oregon
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Torres PAU, De Broe M. Calcium-sensing receptor, calcimimetics, and cardiovascular calcifications in chronic kidney disease. Kidney Int 2012; 82:19-25. [PMID: 22437409 DOI: 10.1038/ki.2012.69] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Renal function impairment goes along with a disturbed calcium, phosphate, and vitamin D metabolism, resulting in secondary hyperparathyroidism (sHPT). These mineral metabolism disturbances are associated with soft tissue calcifications, particularly arteries, cardiac valves, and myocardium, ultimately associated with increased risk of mortality in patients with chronic kidney disease (CKD). sHPT may lead to cardiovascular calcifications by other mechanisms including an impaired effect of parathyroid hormone (PTH), and a decreased calcium-sensing receptor (CaR) expression on cardiovascular structures. PTH may play a direct role on vascular calcifications through activation of a receptor, the type-1 PTH/PTHrP receptor, normally attributed to PTH-related peptide (PTHrP). The CaR in vascular cells may also play a role on vascular mineralization as suggested by its extremely reduced expression in atherosclerotic calcified human arteries. Calcimimetic compounds increasing the CaR sensitivity to extracellular calcium efficiently reduce serum PTH, calcium, and phosphate in dialysis patients with sHPT. They upregulate the CaR in vascular cells and attenuate vascular mineralization in uremic states. In this article, the pathophysiological mechanisms associated with cardiovascular calcifications in case of sHPT, the impact of medical and surgical correction of sHPT, the biology of the CaR in vascular structures and its function in CKD state, and finally the role played by the CaR and its modulation by the calcimimetics on uremic-related cardiovascular calcifications are reviewed.
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Krediet RT. The Manchester Contribution to Peritoneal Dialysis. Perit Dial Int 2011; 31 Suppl 2:S36-8. [DOI: 10.3747/pdi.2009.00181] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Affiliation(s)
- Raymond T. Krediet
- Division of Nephrology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
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15
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Abstract
The definition, evaluation, and classification of the mineral abnormalities and bone disease in chronic kidney disease (CKD) should encompass all three clinical components: • Abnormalities in serum biochemistries • Vascular calcification • Bone abnormalities This principle was discussed at a Kidney Disease: Improving Global Outcomes consensus conference, resulting in a recognition of the shortcomings of the current classification and a recommendation for the development of new terminology. The recommendation was that the term “renal osteodystrophy” be used exclusively to define the bone pathology associated with CKD. The many clinical, biochemical, and imaging abnormalities that have heretofore been identified as correlates of renal osteodystrophy should be defined more broadly as a clinical entity or syndrome called “chronic kidney disease – mineral and bone disorder.” The hope is that this new terminology will enhance communication and facilitate research worldwide.
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Affiliation(s)
- Sharon M. Moe
- Indiana University School of Medicine and Roudebush VAMC, Indianapolis, Indiana, U.S.A
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16
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Ammirati AL, Moysés RMA, Canziani ME. Vascular Calcification in Peritoneal Dialysis Patients. Perit Dial Int 2008. [DOI: 10.1177/089686080802802s04] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Vascular calcification (VC) is being recognized as a common complication at all stages of chronic kidney disease, particularly in patients on dialysis. Traditional and nontraditional cardiovascular risk factors both appear to be involved in the development of VC in this population. Although few studies focusing exclusively on peritoneal dialysis (PD) patients are available, some data support the view that VC constitutes an independent prognostic marker of morbidity and mortality in the PD population. In this review, we discuss the potential pathophysiologic pathways of VC in PD patients, and we examine the relevant clinical data.
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18
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Sherman RA. Briefly Noted. Semin Dial 2007. [DOI: 10.1111/j.1525-139x.1994.tb00812.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Iwasaki Y, Yamato H, Nii-Kono T, Fujieda A, Uchida M, Hosokawa A, Motojima M, Fukagawa M. Insufficiency of PTH action on bone in uremia. Kidney Int 2006:S34-6. [PMID: 16810309 DOI: 10.1038/sj.ki.5001600] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Abnormal bone turnover and mineral metabolism is observed in patients on dialysis. Secondary hyperparathyroidism (SHP) develops in response to mineral metabolism changes accompanying renal failure. As a factor of disease progression, the phenomenon of skeletal resistance to parathyroid hormone (PTH) is observed. With recent advances in the treatment of SHP, over-secretion of PTH can now be controlled. However, blood PTH levels 2 to 3 times higher than normal are considered necessary to maintain normal bone turnover in patients with renal failure. Various causes of skeletal resistance to PTH have been reported, including decrease in PTH receptor in osteoblasts, accumulation of 7-84 PTH fragment, and accumulation of osteoprotegerin. This skeletal resistance to PTH is not only a high-turnover bone accompanying SHP, but may also play a crucial role in the onset of low-turnover bone disease. We have produced a rat model of renal failure with normal level of PTH secretion and analyzed the bone of this model. Our results confirmed that bone turnover is lowered accompanying renal function impairment. We also found that this lowered bone turnover is improved by intermittent administration of PTH. In addition, PTH receptor gene expression is also decreased in low-turnover bone, as is observed in high-turnover bone disease. These findings confirm the presence of skeletal resistance to PTH in low-turnover bone accompanying renal failure. Control of calcium, phosphorus, and PTH levels with the target to maintain normal bone turnover is important in maintaining the quality of life of patients on dialysis.
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Affiliation(s)
- Y Iwasaki
- Department of Health Sciences, Oita University of Nursing and Health Sciences, Oita, Japan.
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Nagano N. Pharmacological and clinical properties of calcimimetics: calcium receptor activators that afford an innovative approach to controlling hyperparathyroidism. Pharmacol Ther 2005; 109:339-65. [PMID: 16102839 DOI: 10.1016/j.pharmthera.2005.06.019] [Citation(s) in RCA: 104] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2005] [Accepted: 06/29/2005] [Indexed: 12/28/2022]
Abstract
Circulating levels of calcium ion (Ca2+) are maintained within a narrow physiological range mainly by the action of parathyroid hormone (PTH) secreted from parathyroid gland (PTG) cells. PTG cells can sense small fluctuations in plasma Ca2+ levels by virtue of a cell surface Ca2+ receptor (CaR) that belongs to the superfamily of G protein-coupled receptors (GPCR). Compounds that activate the CaR and inhibit PTH secretion are termed 'calcimimetics' because they mimic or potentiate the effects of extracellular Ca2+ on PTG cell function. Preclinical studies with NPS R-568, a first generation calcimimetic compound that acts as a positive allosteric modulator of the CaR, have demonstrated that oral administration decreases serum levels of PTH and calcium, with a leftward shift in the set-point for calcium-regulated PTH secretion in normal rats. NPS R-568 also suppresses the elevation of serum PTH levels and PTG hyperplasia and can improve bone mineral density (BMD) and strength in rats with chronic renal insufficiency (CRI). Clinical trials with cinacalcet hydrochloride (cinacalcet), a compound with an improved metabolic profile, have shown that long-term treatment continues to suppress the elevation of serum levels of calcium and PTH in patients with primary hyperparathyroidism (1HPT). Furthermore, clinical trials in patients with uncontrolled secondary hyperparathyroidism (2HPT) have demonstrated that cinacalcet not only lowers serum PTH levels, but also the serum phosphorus and calcium x phosphorus product; these are a hallmark of an increased risk of cardiovascular disease and mortality in dialysis patients with end-stage renal disease. Indeed, cinacalcet has already been approved for marketing in several countries. Calcimimetic compounds like cinacalcet have great potential as an innovative medical approach to manage 1HPT and 2HPT.
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Affiliation(s)
- Nobuo Nagano
- Pharmaceutical Development Laboratories, Kirin Brewery Company, Limited, Takasaki, Gunma, Japan.
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Iwasaki-Ishizuka Y, Yamato H, Nii-Kono T, Kurokawa K, Fukagawa M. Downregulation of parathyroid hormone receptor gene expression and osteoblastic dysfunction associated with skeletal resistance to parathyroid hormone in a rat model of renal failure with low turnover bone. Nephrol Dial Transplant 2005; 20:1904-11. [PMID: 15985520 DOI: 10.1093/ndt/gfh876] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
BACKGROUND Adynamic bone disease (ABD), which is characterized by reduced bone formation and resorption, has become an increasingly common manifestation of bone abnormalities in patients with end-stage renal failure. It has been recognized that skeletal resistance to parathyroid hormone (PTH) underlies the pathogenesis of ABD; however, the mechanisms of such resistance remain unclear. METHODS We established a rat model simulating ABD under chronic renal failure conditions by thyroparathyroidectomy and partial nephrectomy (TPTx-Nx). TPTx-Nx rats were infused subcutaneously with a physiological dose of PTH. We analysed bone histomorphometric parameters and demonstrated gene expression using semi-quantitative reverse transcription-polymerase chain reaction. RESULTS Reduced bone formation was observed in this model, simulating ABD. The reduction was dependent on the degree of renal dysfunction. Bone formation rate was 6.4+/-2.7 microm3/m2/year in TPTx-5/6Nx rats and 22.7+/-7.2 microm3/m2/year in TPTx rats (P<0.05). Osteoblast surface was also significantly depressed (P<0.05) in TPTx-5/6Nx (3.8+/-2.7%) compared with TPTx rats (15.9+/-8.6). The expression of PTH/parathyroid hormone-related peptide (PTHrP) receptor and alkaline phosphatase genes was reduced significantly in TPTx-Nx compared with TPTx rats (P<0.05). Reduced bone formation in TPTx-Nx rats was ameliorated by intermittent injection of pharmacological doses of PTH. CONCLUSIONS Renal dysfunction without secondary hyperparathyroidism induces osteoblast dysfunction and reduces bone formation. Skeletal resistance to PTH develops in renal failure even at low or normal PTH levels, possibly through downregulation of PTH/PTHrP receptor and dysfunction of osteoblasts.
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Affiliation(s)
- Yoshiko Iwasaki-Ishizuka
- Department of Health Sciences, Oita University of Nursing and Health Sciences, Oita, 870-1201, Japan
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22
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Hutchison AJ, Speake M, Al-Baaj F. Reducing high phosphate levels in patients with chronic renal failure undergoing dialysis: a 4-week, dose-finding, open-label study with lanthanum carbonate. Nephrol Dial Transplant 2004; 19:1902-6. [PMID: 15199195 DOI: 10.1093/ndt/gfh282] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND The majority of patients with end-stage renal disease on dialysis are hyperphosphataemic. Lanthanum carbonate has been shown to be a highly effective phosphate binder in pre-clinical studies. A 4-week, open-label, dose-titration trial was conducted to assess the ability of lanthanum carbonate to control phosphate levels in patients with chronic renal failure. METHODS This preliminary study was of 6 weeks duration: 2 weeks of washout followed by 4 weeks of dose titration. Patients (n = 59) were titrated on the basis of weekly serum phosphate levels from a daily dose of 375 mg lanthanum carbonate to a maximum dose of 2250 mg. Patients were maintained on the dose that controlled serum phosphate to between 1.30 and 1.80 mmol/l (4.03-5.58 mg/dl). Serum phosphate levels represented the main efficacy assessment. Safety was also evaluated. RESULTS Most patients were successfully titrated to 1500 and 2250 mg lanthanum/day (mean dose at end of titration: 1278 mg). At completion of the study 70% of patients achieved a serum phosphate of <or=1.80 mmol/l. The use of lanthanum carbonate in patients undergoing continuous ambulatory peritoneal dialysis or haemodialysis was generally well tolerated. CONCLUSIONS Lanthanum carbonate, a new non-aluminium, non-calcium phosphate binder, effectively reduces serum phosphate levels. Results of longer-term efficacy and safety studies are awaited with interest.
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Affiliation(s)
- Alastair J Hutchison
- Manchester Institute of Nephrology and Transplantation, The Royal Infirmary, Manchester, UK.
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Parfitt AM. Renal bone disease: a new conceptual framework for the interpretation of bone histomorphometry. Curr Opin Nephrol Hypertens 2003; 12:387-403. [PMID: 12815335 DOI: 10.1097/00041552-200307000-00007] [Citation(s) in RCA: 107] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
My purpose in this article is to restore the histologic appraisal of renal bone disease to the mainstream of bone and mineral metabolism from which it has been separated for many years. Historically, both the two major components were found in varying degrees in most patients, although one or other of them often predominated. For more than 15 years bone biopsy has been used almost exclusively to classify individual patients into hyperparathyroid, osteomalacic, mixed and adynamic categories according to rigid non-overlapping criteria, and remarkably few histologic data have been reported. All metabolic bone diseases result from disordered bone remodeling, the physiologic mechanism for replacing bone that has become too old to carry out its mechanical or metabolic functions. Bone remodeling is not directly concerned with the regulation of plasma calcium, which reflects the level of equilibration at quiescent bone surfaces between systemic and bone extracellular fluid set by parathyroid hormone. The separation of remodeling from homeostasis explains the concurrence of increased turnover and decreased plasma calcium in chronic renal failure; it is the homeostatic system, rather than the remodeling system, which is resistant to parathyroid hormone. The effect of mild hyperparathyroidism is a nonspecific increase in bone turnover, of which the best index is the bone formation rate measured by double tetracycline labeling expressed per unit of bone surface. Increased turnover is always accompanied by increased reversible mineral deficit. In prolonged hyperparathyroidism there is also accelerated irreversible bone loss manifested mainly as thinning of cortical bone, detectable in chronic renal failure before any symptoms, due to increased resorption depth on the endocortical surface. In severe hyperparathyroidism resorbed bone is replaced, not by a lesser quantity of normal bone, but by a mixture of vascular fibrous tissue and woven bone, referred to as osteitis fibrosa. In osteomalacia there is increased accumulation of osteoid, due not to increased turnover, but to prolongation of mineralization lag time, which in conjunction with increased thickness, surface and volume of osteoid is diagnostic. Converting histomorphometric data into category assignment discards most of the useful information, which can be retained by two-dimensional representation of severity. For the hyperparathyroid dimension, bone formation rate measured by double tetracycline labeling expressed per unit of bone surface is the most useful although not ideal. For the osteomalacic dimension a mineralization index was constructed that is unaffected by age or race. In patients with osteitis fibrosa, bone formation rate per unit of bone surface and mineralization index were inversely correlated. For the third dimension a structure/formation index was constructed which increases with age in healthy women and shows weak inverse correlation with bone formation rate. The structure/formation index is lower than normal in patients with osteitis fibrosa, and should be useful in the study of osteopenia in chronic renal failure. Bone formation rate is low in osteomalacia, but some patients have subnormal rates through quite a different mechanism. The frequency of this finding has been overestimated for several reasons: failure to exclude atypical osteomalacia (increased surface and volume but not thickness of osteoid), use of inappropriate reference values, and failure to measure the bone formation rate on endocortical and intracortical surfaces. In healthy women bone formation rate can be zero on the cancellous surface alone. Low bone formation rate is sometimes due to diabetes but most often is the expected response to subnormal parathyroid hormone secretion accompanying an excess of calcium, a situation recognized only recently because of improvement in parathyroid hormone assay methodology. Low cancellous bone formation rate should not increase fracture risk because turnover is much lower in the peripheral than in the central skeleton, and all reports of increased fracture risk are flawed or open to different interpretation. Low bone formation rate is associated with reduced skeletal buffering of calcium and increased soft tissue calcification. This is not a new disease needing its own treatment, however, but represents the final stage of skeletal adaptation to a surfeit of calcium. The concept of adynamic bone disease has been harmful by directing attention away from the most important consequence of over-treatment of hyperparathyroidism.
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Affiliation(s)
- A Michael Parfitt
- Division of Endocrinology and Center for Osteoporosis and Metabolic Bone Disease, University of Arkansas for Medical Sciences, Arkansas, USA.
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Nakashima A, Yorioka N, Doi S, Ueda C, Usui K, Shigemoto K, Harada S. Radial bone mineral density in hemodialysis patients with adynamic bone disease. Int J Artif Organs 2003; 26:200-4. [PMID: 12703885 DOI: 10.1177/039139880302600304] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Adynamic bone disease (ABD) has attracted attention as the most frequent type of renal osteodystrophy, but there are few reports about the bone mineral density (BMD) in ABD patients. This study investigated the BMD in hemodialysis patients with ABD and with relatively normal bone turnover. We measured the BMD of the distal one-third of the radius by dual-energy X-ray adsorptiometry. In the ABD group (intact PTH<65 pg/ml, intact osteocalcin<30 ng/ml), there were 19 men and 17 women with a mean age of 56.4 +/- 12.0 years. In the relatively normal bone turnover group (intact PTH: 120-250 pg/ml), there were 24 men and 16 women with a mean age of 57.1 +/- 14.7 years. Although there were no significant differences between the two groups with respect to age, gender, and duration of hemodialysis, a significant increase of the BMD and the calcium x phosphate product was observed in the ABD group (radial BMD: 0.648 +/- 0.137 g/cm2 versus 0.572 +/- 0.132 g/cm2, calcium x phosphate product: 57.53 +/- 14.92 mg2/dl2 versus 49.76 +/- 12.13 mg2/dl2). These findings suggest that an increase in radial BMD may not be a useful marker of the improvement in bone lesions in ABD patients.
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Affiliation(s)
- A Nakashima
- Department of Internal Medicine, Harada Hospital, Hiroshima, Japan
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26
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Sanchez CP, He YZ. Effects of thyroparathyroidectomy, exogenous calcium, and short-term calcitriol therapy on the growth plate in renal failure. J Am Soc Nephrol 2003; 14:148-58. [PMID: 12506147 DOI: 10.1097/01.asn.0000039565.56011.be] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
Several factors have been implicated in the development of adynamic bone, including the use of calcium-containing phosphate binding agents, aggressive calcitriol therapy, and parathyroidectomy. To evaluate the effects of these interventions on the growth plate, weanling rats underwent sham nephrectomy (Control, n = 10) and 5/6 nephrectomy (Nx). In the nephrectomized group, animals underwent (a) thyroparathyroidectomy (Nx-TPTX, n = 7), (b) received exogenous calcium (Nx-Calcium, n = 10), (c) received short-term calcitriol therapy (Nx-D, n = 10), or (d) nephrectomized control (Nx-Control, n = 10). Higher serum calcium and lower PTH levels were demonstrated in Nx-Calcium and Nx-D animals. A decline in growth was demonstrated in Nx-Calcium and Nx-TPTX accompanied by shorter tibial lengths. The width of the growth plate was wider in Nx-Calcium animals due to an increase in the width of the hypertrophic zone and a decrease in the proliferative zone; these changes were accompanied by an impairment of chondroclastic resorption, lower gelatinase B/MMP-9 activity, decline in insulin-like growth factor-I (IGF-I) receptor, and lower histone-4 mRNA expression. Such findings in the growth plate, may partially contribute to the diminution of growth in these animals. Although growth was impaired in the Nx-TPTX animals, there were no significant changes demonstrated in the growth plate cartilage. Histone-4 transcripts, IGF-I receptor expression, and histochemical staining for chondroclasts were decreased in Nx-D animals. Thus, treatments used in the management of secondary hyperparathyroidism in renal failure have diverse effects on the growth plate of the young skeleton, and concurrent use of these interventions needs further evaluation.
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Affiliation(s)
- Cheryl P Sanchez
- Department of Pediatrics, University of Wisconsin Medical School, Madison, Wisconsin 53706, USA.
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27
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Abstract
Bone disease is observed in 75-100% of patients with chronic renal failure as the glomerular filtration rate (GFR) falls below 60 ml/minute. Hyperparathyroid (high turnover) bone disease is found most frequently followed by mixed osteodystrophy, low-turnover bone disease, and osteomalacia. With advancing renal impairment, "skeletal resistance" to parathyroid hormone (PTH) occurs. To maintain bone turnover, intact PTH (iPTH) targets from two to four times the upper normal range have been suggested, but whole PTH(1-84) assays indicate that amino-terminally truncated fragments, which accumulate in end-stage renal disease (ESRD), account for up to one-half of the measured iPTH. PTH levels and bone-specific alkaline phosphatase (BSAP) provide some information on bone involvement but bone biopsy and histomorphometry remains the gold standard. Calcitriol and calcium salts can be used to suppress PTH and improve osteomalacia but there is growing concern that these agents predispose to the development of vascular calcification, cardiovascular morbidity, low-turnover bone disease and fracture. Newer therapeutic options include less calcemic vitamin D analogues, calcimimetics and bisphosphonates for hyperparathyroidism, and sevelamer for phosphate control. Calcitriol and hormone-replacement therapy (HRT) have been shown to maintain bone mineral density (BMD) in certain patients with end-stage renal disease (ESRD). After renal transplantation, renal osteodystrophy generally improves but BMD often worsens. Bisphosphonate therapy may be appropriate for some patients at risk of fracture. When renal bone disease is assessed using a combination of biochemical markers, histology and bone densitometry, early intervention and the careful use of an increasing number of effective therapies can reduce the morbidity associated with this common problem.
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Affiliation(s)
- Grahame Elder
- Garvan Institute of Medical Research, Sydney, NSW, Australia
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28
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Parker CR, Blackwell PJ, Freemont AJ, Hosking DJ. Biochemical measurements in the prediction of histologic subtype of renal transplant bone disease in women. Am J Kidney Dis 2002; 40:385-96. [PMID: 12148113 DOI: 10.1053/ajkd.2002.34535] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Renal transplant osteodystrophy encompasses several histologic subtypes. Bone histomorphometric examination reliably distinguishes these groups but is invasive, is time-consuming, and delays diagnosis. Establishing a noninvasive method of correctly predicting histologic subtype in an individual to direct management is an attractive proposition. We identified 19 female renal transplant recipients with histologic evidence of hyperparathyroid bone disease (HPTH) and 14 with adynamic bone (ADB). We evaluated serum osteocalcin and bone-specific alkaline phosphatase as bone formation markers and urinary hydroxyproline (Hypro) and deoxypyridinoline cross-links as bone resorption markers. Mean concentrations for all markers were higher in the HPTH group, reaching significance for Hypro (HPTH, 24.8 +/- 4.2 micromol/mmol creatinine; ADB, 13.2 +/- 5.0 micromol/mmol creatinine; P = 0.01). A cutoff of 16.4 micromol/mmol creatinine for Hypro (Youden's index, 0.65) gave a sensitivity of 93% and specificity and positive predictive value (PPV) of 72% in predicting HPTH. In combination, Hypro greater than 16.4 micromol/mmol creatinine and parathyroid hormone greater than 80 pg/mL gave a specificity of 100%, sensitivity of 32%, and PPV of 100%. Conversely, for predicting ADB, Hypro less than 15.1 micromol/mmol creatinine (Youden's index, 0.45) gave a specificity of 93%, sensitivity of 53%, and PPV of 91%. Hypro less than 15.1 micromol/mmol creatinine plus osteocalcin less than 6.8 microg/L gave a specificity of 84.2%, sensitivity of 64.3%, and PPV of 75%. Significant associations between markers and histomorphometry were evident only for Hypro and osteocalcin (with osteoblast surface) and all markers (except deoxypyridinoline cross-links) with cortical volume. Markers have limited utility in identifying histologic subtype (Hypro was most effective) and, with the exception of Hypro and osteocalcin, showed little association with cell surface markers of bone cell activity.
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Affiliation(s)
- Cornelle R Parker
- Division of Mineral Metabolism and Department of Clinical Chemistry, City Hospital, Nottingham, United Kingdom.
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Abstract
There are a number of pathologies that are associated with the development of renal failure. Once renal function has deteriorated beyond a point where life is not sustainable without dialysis, new sets of pathologic processes develop. These are, in part, related to the continuation of poor renal function and to the process of dialysis itself. This article addresses the processes that are believed to be due to dialysis, among which are disorders of bone, deposition of metals and amyloid within a number of tissues, and local problems such as inflammation and tumors related to the dialysis site.
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Affiliation(s)
- A J Freemont
- Department of Osteoarticular Pathology, The Medical School, University of Manchester, United Kingdom.
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Gokal R. Peritoneal Dialysis in the 21st Century: An Analysis of Current Problems and Future Developments. J Am Soc Nephrol 2002. [DOI: 10.1681/asn.v13suppl_1s104] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
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Affiliation(s)
- W G Goodman
- Division of Nephrology, Department of Medicine, UCLA School of Medicine, 9005, Los Angeles, CA, USA.
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Gupta A, Kallenbach LR, Zasuwa G, Divine GW. Race is a major determinant of secondary hyperparathyroidism in uremic patients. J Am Soc Nephrol 2000; 11:330-334. [PMID: 10665940 DOI: 10.1681/asn.v112330] [Citation(s) in RCA: 92] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
In the general population, blacks have higher parathyroid gland mass and circulating parathyroid hormone (PTH) levels than whites. This may predispose black patients to more severe parathyroid disease when renal failure develops. Therefore, racial differences in the severity of uremic hyperparathyroidism were examined in a population of patients with end-stage renal disease (ESRD). Among ESRD patients receiving hemodialysis or peritoneal dialysis, two or more values of intact PTH (immunoradiometric assay, pg/ml) obtained at least 90 d apart were available in 1270 prevalent cases (61.1% blacks, 51% males, and 31.1% diabetic), including 466 incident cases with onset of ESRD after 1993. Maximum PTH levels were analyzed as a function of race, gender, age, diabetic status, and levels of serum calcium, phosphorus, alkaline phosphatase, and aluminum. Using a stepwise multiple regression model, the determinants of maximum PTH in the order of their importance were black race, serum phosphorus, absence of diabetes, younger age, serum calcium, and female gender. The maximum PTH levels averaged 641.7 in blacks and 346.0 in whites after adjusting for age, gender, diabetic status, serum calcium, and phosphorus (P < 0.0001). In blacks compared with whites, the odds ratio (95% confidence interval) for adynamic bone disease (maximum PTH <150 pg/ml) was 0.26 (0.17 to 0.41), whereas the odds ratio for hyperparathyroid bone disease (mean PTH >500 pg/ml) was 4.4 (2.10 to 9.25). Race is a major independent determinant of uremic secondary hyperparathyroidism. Among ESRD patients, blacks may be at an increased risk for hyperparathyroid bone disease and whites for adynamic bone disease.
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Affiliation(s)
- Ajay Gupta
- Division of Nephrology and Hypertension, Henry Ford Hospital, Detroit, Michigan
| | - Lee R Kallenbach
- Department of Biostatistics and Research Epidemiology, Henry Ford Hospital, Detroit, Michigan
| | - Gerard Zasuwa
- Division of Nephrology and Hypertension, Henry Ford Hospital, Detroit, Michigan
| | - George W Divine
- Department of Biostatistics and Research Epidemiology, Henry Ford Hospital, Detroit, Michigan
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Abstract
Histology and histomorphometry are the two primary methods of using bone biopsies to diagnose renal osteodystrophy. However, appropriate diagnoses can only be rendered when there is complete understanding of bone structure, of they way bone is processed for histology, and of the manner in which analyses of samples proceeds. In the future, modern applied molecular biology techniques will be added to these standards and redefine diagnoses.
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Affiliation(s)
- T Freemont
- Department of Pathology, University of Manchester, United Kingdom
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Parker CR, Freemont AJ, Blackwell PJ, Grainge MJ, Hosking DJ. Cross-sectional analysis of renal transplantation osteoporosis. J Bone Miner Res 1999; 14:1943-51. [PMID: 10571695 DOI: 10.1359/jbmr.1999.14.11.1943] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
We report a cross-sectional study of 54 adult female renal transplant recipients. We measured bone mineral density (BMD) of the lumbar spine, femoral neck, total hip, and mid- and total radius, and 38 patients underwent transiliac crest bone biopsy. Osteopenia was widespread with 31/54 (57%) of patients osteoporotic at one or more sites. Seventeen out of 54 (32%) of the patients had a prevalent low-trauma fracture. There was a clear trend in BMD reduction across spine, hip and midradius, with the predominantly cortical midradial site showing the greatest loss. We found no relationship between BMD and body mass index, parathyroid hormone (PTH), dose of immunosuppressant, years since transplantation, age at menopause, or years since menopause. Histologically, abnormal biopsies could be classified into three categories: hyperparathyroid (n = 20), adynamic (n = 14), and osteomalacic (n = 2). Mean PTH was lower (p = NS) and mean cumulative prednisolone dose was higher (p = 0.04) in the adynamic group compared with the hyperparathyroid group, but because of overlap between groups neither was an effective discriminator of histology. We suggest that bone biopsy is indicated in these patients to direct appropriate treatment. At the cellular level, there were significant negative correlations between osteoclast function (eroded surface, r = 0.47, p = 0.003) and osteoblast numbers (osteoblast surface, r = -0.40, p = 0.01) and cumulative exposure to prednisolone. We postulate that suppression of osteoblast function by prednisolone with unopposed bone resorption may result in relative hypercalcaemia and low PTH. This progressive reduction in bone turnover may promote or prolong the adynamic state.
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Affiliation(s)
- C R Parker
- Division of Mineral Metabolism, City Hospital, Nottingham, United Kingdom
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Abstract
BACKGROUND Renal osteodystrophy (ROD) is still one of the major long-term complications in end-stage renal disease leading to considerable morbidity. Despite some progress in understanding the pathogenesis of secondary hyperparathyroidism (sHPT) during recent years, prevention and treatment of ROD is still suboptimal, requiring surgical parathyroidectomy in 6 to 10% of all patients on dialysis after 10 years. In addition, the spectrum of bone lesions has changed, with non-aluminum-related adynamic bone disease (ABD) found in up to 43% of peritoneal dialysis (PD) patients. METHODS Current recommendations concerning prevention of ROD in PD based on the literature and personal recent data were reviewed. The focus is on (i) the importance of early prophylactic intervention to prevent parathyroid gland hyperplasia, (ii) the pathogenesis of ABD, and (iii) the role of metabolic acidosis in ROD. RESULTS There is ample evidence that sHPT starts early during the course of renal failure and results from both hypersecretion of PTH by parathyroid cells and glandular hyperplasia. As shown by experimental and clinical studies, established parathyroid cell hyperplasia is hardly reversible by pharmacological means, and therefore prevention of parathyroid cell proliferation needs to start early. Recent data from randomized trials document the efficacy and safety of low dose active vitamin D (0.125 to 0.25 microgram/day) and/or an oral calcium substitute to prevent progression of sHPT in patients with mild to moderate renal failure. Since little is known about the pathogenesis, natural course and clinical impact of ABD in PD, specific therapeutic concepts have not yet been generated. Diabetes and advanced age are established risk factors, whereas the role of calcium and vitamin D overtreatment or the type of dialysis (PD vs. HD) are still controversial. Currently no evidence for different functional behavior of the parathyroids in ABD and sHPT has been found. The role of circulating or local factors such as cytokines, growth factors or the presence of advanced glycation end-product (AGE)-modified matrix proteins for the pathogenesis of either type of ROD deserves further investigation. Avoiding oversuppression of parathyroid gland and the use of low calcium dialysate may help prevent ABD. There is growing evidence that a correction of metabolic acidosis will influence ROD by both direct effects on the bone and on parathyroid cell function. New dialysate composition for CAPD with a high HCO3 concentration will allow normalization of acid-based metabolism in PD patients. Their effects on ROD under long term conditions remain to be determined. CONCLUSION Therapeutic efforts should aim to prevent the development of parathyroid gland hyperplasia and sHPT early during the course of renal failure, and should include the use of low dose vitamin D therapy and oral calcium substitution as well as correction of metabolic acidosis. Concerning ABD, more information is needed regarding the causes and consequences of this type of bone lesion to develop a more specific therapy.
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Affiliation(s)
- T Weinreich
- Department of Internal Medicine, University Hospital, Zürich, Switzerland.
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Affiliation(s)
- A M Parfitt
- Division of Endocrinology and Metabolism and Center for Osteoporosis and Metabolic Bone Disease, University of Arkansas for Medical Sciences, Little Rock 72205-7199, USA
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Fournier A, Oprisiu R, Hottelart C, Yverneau PH, Ghazali A, Atik A, Hedri H, Said S, Sechet A, Rasolombololona M, Abighanem O, Sarraj A, El Esper N, Moriniere P, Boudailliez B, Westeel PF, Achard JM, Pruna A. Renal osteodystrophy in dialysis patients: diagnosis and treatment. Artif Organs 1998; 22:530-57. [PMID: 9684690 DOI: 10.1046/j.1525-1594.1998.06198.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
This article reviews the clinical, biological, radiological, and pathological procedures and their respective indications for the practical diagnosis of the following various histological patterns of renal osteodystrophy: osteitis fibrosa due to parathyroid hormone (PTH) hypersecretion: osteomalacia or rickets due to native vitamin D deficiency and/or aluminum overload; and adynamic bone disease (ABD) due to aluminum overload and/or PTH secretion oversuppression. Our advice regarding bone biopsy is to restrict it to patients with symptoms and hypercalcemia, especially those who have been previously exposed to aluminum. In other cases, we propose relying merely on the determination of the plasma concentrations of calcium, protide, phosphate, bicarbonate, intact PTH, aluminum, 25(OH)D3, and alkaline phosphatase (total and bony if hepatic disease is associated) to choose the appropriate treatment. Because of the danger of the desferrioxamine treatment necessary to chelate and remove aluminum, the suspicion of aluminic bone disease (osteomalacia or ABD) will always be confirmed by a bone biopsy. In the case of nonaluminic osteomalacia, correction of the vitamin D deficiency by native vitamin D or 25(OH)D3, and of the calcium deficiency and acidosis by alkaline salts of calcium and if necessary sodium bicarbonate are sufficient to cure the disease. In the case of nonaluminic ABD, the stimulation of PTH secretion by the discontinuation of 1alpha hydroxylated vitamin D and the induction of a negative calcium balance during dialysis by decreasing the calcium concentration in the dialysate will allow an increase of the CaCO3 dose to correct for hyperphosphatemia without inducing hypercalcemia. For hyperparathyroidism, i.e., plasma intact PTH levels greater than two- or four-fold the upper limit of normal levels (according to the absence or presence of previous aluminum exposure), the treatment will consist in increasing the CaCO3 dose to correct for hyperphosphatemia together with a decrease of the calcium concentration in the dialysate if the dose of CaCO3 is so high that it induces hypercalcemia. When the hyperphosphatemia has been corrected and there is still a low or normal corrected plasma calcium level, 1alpha(OH)D3 in an oral bolus 2 or 3 times a week should be given at the minimal dose of 1 microg. When the PTH level stays above 400 pg while hypercalcemia occurs and hyperphosphatemia persists, surgical subtotal parathyroidectomy is recommended or the injection of calcitriol into the big nodular hyperplastic parathyroid glands under sonography control in high surgical risk patients. Special recommendations are given for children.
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Affiliation(s)
- A Fournier
- Nephrology Department, Amiens University Hospital, France
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Stein MS, Packham DK, Ebeling PR, Wark JD, Becker GJ. Prevalence and risk factors for osteopenia in dialysis patients. Am J Kidney Dis 1996; 28:515-22. [PMID: 8840940 DOI: 10.1016/s0272-6386(96)90461-8] [Citation(s) in RCA: 112] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Dialysis patients are at risk for low bone mineral density (BMD) consequent of hyperparathyroidism, 1,25-dihydroxyvitamin D deficiency, previous immunosuppression, chronic acidosis, secondary amenorrhea, and chronic heparin and aluminum exposure. We wanted to determine the prevalence and distribution of osteopenia and the influence of risk factors for osteopenia in dialysis patients. Dual energy x-ray absorptiometry was used to record BMD at the lumbar spine (LS), hip, and nondominant forearm. Results were expressed as Z-scores (standard deviations from the mean of a healthy age- and gender-matched reference population). Osteopenia was defined as a Z-score worse than -2. In the 250 dialysis patients studied, the prevalence of osteopenia at the LS, femoral neck (FN) and ultradistal radius (UD) was 8%, 13% and 20%, respectively. The median Z-scores at these sites were all significantly different from the healthy reference population median of 0 and were 0.29 (P = 0.008), -0.67 (P < 0.001), and -1.01 (P < 0.001), respectively. Previous transplantation was associated with as much as a one Z-score lower BMD at the FN (P = 0.0069) and UD (P = 0.0011) and a marginally significant reduction at the LS (P = 0.0777). Previous parathyroidectomy was associated with a markedly higher LS BMD (P = 0.0001) and a higher BMD at the FN (P = 0.0017) but not the UD (P = 0.3691). A history of secondary amenorrhea was associated with a lower FN BMD (P = 0.0047) but not a significantly lower BMD at the LS (P = 0.0978) or UD (P = 0.2327). In hemodialysis patients without a history of transplantation, parathyroidectomy, or secondary amenorrhea, there was no correlation between Z-score at any site and duration of dialysis. Thus, osteopenia in dialysis patients occurs in both axial and appendicular sites and sites of compact and cancellous bone. It is more common with previous transplantation and secondary amenorrhea, whereas a history of parathyroidectomy is associated with increased BMD. No relationship was found between BMD and duration of hemodialysis, which suggests that important changes in BMD occur during the predialysis stage of chronic renal failure.
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Affiliation(s)
- M S Stein
- Department of Medicine, University of Melbourne, Australia
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Sanchez CP, Salusky IB. The renal bone diseases in children treated with dialysis. ADVANCES IN RENAL REPLACEMENT THERAPY 1996; 3:14-23. [PMID: 8620364 DOI: 10.1016/s1073-4449(96)80037-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Renal osteodystrophy represents a spectrum from high- to low-turnover bone lesions. The specific pattern, however, may change during selected therapeutic interventions. As in the past, osteitis fibrosa remains the most frequent histologic lesion in pediatric patients on dialysis, although recently the prevalence of low-turnover bone lesions without aluminum toxicity has been increasing in the pediatric population. This may be a consequence of aggressive calcitriol and calcium therapy. The different factors involved in the development of secondary hyperparathyroidism include hyperphosphatemia, hypocalcemia, altered vitamin D synthesis, impairments in parathyroid hormone (PTH) secretion and metabolism, and, recently, possible downregulation of renal PTH/PTH-rP messenger RNA receptor. New developments in molecular biology have demonstrated the relationship between vitamin D and PTH. The use of high-dose pulse intravenous, intraperitoneal, and oral calcitriol therapy has significantly decreased serum PTH levels and retarded the progression of osteitis fibrosa. These therapeutic interventions, however, may have led to the development of adynamic bone lesions. The impact of adynamic bone lesions in the young and growing skeleton remains to be determined.
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Affiliation(s)
- C P Sanchez
- Department of Pediatrics, UCLA School of Medicine, CA 90095-1752, USA
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