Low-Turnover Bone Disease in Hypercalcemic Hyperparathyroidism After Kidney Transplantation

Hypercalcemia in persistent secondary hyperparathyroidism after kidney transplantation is considered to result from increased bone resorption. Bone biopsies' studies, however, have never been performed in these patients. Bone biopsies after double tetracycline labeling were obtained from 17 patients with hypercalcemic hyperparathyroidism and an estimated glomerular filtration rate > 30 mL/min/1.73 m2. Serologic bone markers, calcitriol, intact fibroblast growth factor-23 (iFGF-23), and serum and 24h urine concentration of calcium and phosphate were measured in all patients. Tubular maximum for phosphate corrected for GFR (TmP/GFR), and the fractional excretion of calcium (FeCa) were calculated. High-turnover renal osteodystrophy (ROD) was present in nine and low-turnover ROD in eight patients. The bone formation rate was significantly associated with bone alkaline phosphatase, c-telopeptide and osteocalcin. In patients with high turnover ROD, osteocalcin was also significantly higher than in patients with decreased bone formation. The FeCa was normal or below normal in 14/17 patients. TmP/GFR was below normal in all patients. Neither intact PTH nor iFGF-23 was associated with TmP/GFR, FeCa or any histomorphometric bone parameter. We conclude that hypercalcemia of posttransplant hyperparathyroidism can be associated with high or low turnover bone disease. Decreased calcium excretion suggests an additive tubular effect on hypercalcemia.     

Fracture risk after parathyroidectomy among chronic hemodialysis patients

The impact of parathyroidectomy (PTX) on the long-term risks for hip and other fractures is unknown. Uncontrolled case series have reported an increase in bone mineral density after PTX. However, very low serum parathyroid hormone levels have been associated with decreased bone mineral density, adynamic bone disease, and fractures. This study compared long-term fracture rates among hemodialysis patients who underwent PTX with a matched control group. Data were obtained from the US Renal Data System. Patients who underwent a first PTX while receiving hemodialysis were matched with up to three control patients by age, race, gender, year of dialysis initiation, primary cause of renal failure, and the dosage of intravenous vitamin D used before PTX. Patients with a history of fracture or renal transplantation were excluded. Study outcomes were incident hip, vertebral, and distal radius-wrist fractures identified using hospitalization codes. Incident hip fracture rates in the PTX and matched control groups were 6.0 and 9.3 fractures per 1000 person-years, respectively. After adjustment, PTX was associated with a significant 32% lower risk for hip fracture (95% confidence interval 0.54 to 0.86; P = 0.001) and a 31% lower risk for any analyzed fracture (95% confidence interval 0.57 to 0.83; P < 0.001) compared with matched control subjects. Fracture risks were lower among hemodialysis patients who underwent PTX compared with matched control subjects. Surgical amelioration of secondary hyperparathyroidism may outweigh the risk of parathyroid hormone oversuppression in terms of bone health.     

Studies of serum bone Al-P isoenzyme and serum osteocalcin in patients on maintenance hemodialysis

This report describes an investigation of 128 patients on maintenance hemodialysis. Their serum bone Al-P isoenzyme (Al-P III) values were measured by the Rosalki method, and simultaneous estimations were made of their serum osteocalcin levels as a diagnostic indicator of renal osteodystrophy (ROD). ROD was evaluated clinically from Jensen's criteria, based on a four-stage classification of the radiographic evidence for subperiosteal resorption: no change (stage 0), minor change (stage I), and definite change (stages IIa and IIb). The serum Al-P III levels in the stage IIa and IIb patients showed significantly elevated values (p less than 0.01), i.e., 4.98 +/- 6.23 and 20.51 +/- 13.46 KAU, respectively. In contrast, their serum osteocalcin levels were not appreciably different. Patients with elevated N-PTH values of 0.30 ng/ml or more were found to have serum Al-P III levels of 20 KAU or more, and all of these patients were categorized under the stage IIb classification. It is concluded therefore that in chronic renal failure patients on hemodialysis, measurements of the serum Al-P III are highly useful for diagnosing ROD, and may also be considered as a critical parameter for assessing the indication for parathyroidectomy (PTX).     

Clinical study of total parathyroidectomy and autotransplantation for secondary hyperparathyroidism]

From April 1983 to September 1991 total parathyroidectomy (PTX) and parathyroid autotransplantation were carried out in 27 patients for secondary hyperparathyroidism. Of these patients, 13 were males and 14 were females. Their average age was 43 years old and their mean duration of dialysis was 126.4 months. As preoperative clinical symptoms, bone pain was observed in 19 cases, joint pain in 18, decrease of height in 7, pruritus in 3, muscle pain in 2, red eyes in 2 and others in 2. As roentgenographic findings, subperiosteal bone resorption and skull-salt and pepper were demonstrated in 26 cases, rugger jersey spine in 15, soft tissue calcification in 11, and pathological fractures in 4. Four parathyroid glands were removed in 23 cases, three glands in 4. Serum calcium level decreased remarkably within 24 hours after parathyroidectomy in all cases. The average total weight of parathyroid glands was 4.48 g. The preoperative diagnostic accuracy of echogram was 94% and that of CT scan was 90%. The clinical improvement after PTX was excellent in 12 cases and good in 11. The roentgenographic improvement of skull and/or finger bone more than one year after PTX was excellent in 11 cases and good in 11. Judging from histopathological findings of the bone, the clinical and roentgenographic improvement was observed better in the osteitis fibrosa group than in mild group. A significant correlation was found between the level of preoperative c-PTH and the weight of resected parathyroid glands. The level of preoperative ALP correlated with intact-PTH and was higher in the osteitis fibrosa group than in the mild group.(ABSTRACT TRUNCATED AT 250 WORDS)     

Postoperative variations of bone turnover markers in uremic patients with secondary hyperparathyroidism after parathyroidectomy

Objective To study shortdated postoperative variation characteristics of bone turnover markers (BTMs) in uremic patients with secondary hyperparathyroidism (SHPT) underwent parathyroidectomy (PTX). Methods A total of 19 uremic patients with SHPT underwent successful PTX, hospitalized in the Department of Nephrology, The First Affiliated Hospital of Nanjing Medical University from January 2017 to April 2017, were enrolled in the study. The operative model for all enrolled patients was total parathyroidectomy with forearm autotransplantation. The baseline epidemiological and clinical data before PTX and the levels of serum intact parathyroid hormone (iPTH) and serum BTMs after PTX (in the 1st, 3rd and 7th postoperative day) were collected. The correlations between serum iPTH and serum BTMs before PTX and the trend analysis of serum BTMs after PTX were studied. Results The levels of serum iPTH, serum alkaline phosphatase (ALP), serum type Ⅰcollagen cross-linked C-telopeptides (CTX) and serum tartrate-resistant acid phosphatase 5b (TRACP-5b) before PTX were increased, in turn, (1512.4±612.0) ng/L, 267.4(153.1, 424.2) U/L, (5.78±1.15) μg/L and (8.79±4.61) IU/L. Positive correlations between ALP and iPTH (r=0.577, P=0.010), TRACP-5b and iPTH (r=0.640, P=0.003), and ALP and TRACP-5b (r=0.698, P=0.001) were found. The serum levels of ALP increased, while the serum levels of CTX and TRACP-5b decreased within 7 days after PTX. Conclusions Renal osteodystrophy (ROD) with high bone turnover rate is common in uremic patients with severe SHPT. The activities of osteoblast and osteoclast are up-regulated in coupling with positive correlations to serum levels of iPTH. Increased activities of osteoblast and decreased activities of osteoclast were found shortdated postoperatively.     

The renal osteodystrophy pattern in Brazil and Uruguay: an overview

BACKGROUND: The prevalence of the types of renal osteodystrophy (ROD) has changed in the last two decades. This study evaluates the prevalence and determining factors of the types of ROD in two countries in South America. METHODS: Symptomatic patients who underwent bone biopsies for diagnostic purposes (1985 through 2001) were included in the study. In Brazil, a total of 2340 patients were reviewed, 93.1% on hemodialysis (HD), and 6.9% on continuous ambulatory peritoneal dialysis (CAPD). In Uruguay, 167 patients on hemodialysis were included. Uncalcified bone samples were analyzed in order to diagnose the different types of ROD. RESULTS: Comparing the 1980s to the 1990s, the prevalence of Brazilian patients with hyperparathyroid bone disease (HP) increased from 32.3% to 44.0%, while Al overload decreased from 61.3% to 42.4%. A logistic regression analysis showed that the main factors associated with HP included female gender, age of less than 40 years, black patients, longer time on dialysis, and absence of Al overload. In Uruguay, HP also increased over time from 31.8% to 70.5% (P < 0.05), while Al overload decreased from 42% to 27% (P < 0.05). CONCLUSION: A better control of Al overload may lead to a change in histologic pattern, as evidenced by the increasing prevalence of HP.     

甲状旁腺全切除加前臂移植治疗尿毒症继发性甲状旁腺功能亢进

目的观察甲状旁腺全切除(PTX)加自体前臂移植术治疗尿毒症维持性透析患者严重继发性甲状旁腺功能亢进(SHPT)的临床疗效。方法回顾性分析我院12例接受PTX加自体前臂移植术的患者资料,包括术前B超定位与手术切除的甲状旁腺定位的关系,以及术前后血甲状旁腺激素(iPTH)、血钙磷、红细胞比容(Hct)、甘油三酯、透析充分性(Kt／V、UUR)的变化。结果 11例患者术中所切除的甲状旁腺结节与术前B超定位完全一致,1例患者在手术探查中新发现1个较小的约0．5 cm3甲状旁腺结节。术后血钙、磷及其乘积较术前明显下降,差异有统计学意义。术后各时间点(1周、1、3、6、12个月)血iPTH较术前明显下降,差异有统计学意义。术后3个月甘油三酯[(1．78±0．61)mmol／L]较术前[(2．07±0．47)mmol／L]明显下降,Hct (0．31±0．06)较术前(0．26±0．05)明显提高;透析充分性Kt／V、UUR(1．668±0．173、0．696±0．041)较术前(1．567±0．195、0．667±0．054)升高,差异均有有统计学意义。结论甲状旁腺全切除加自体前臂移植能有效治疗SHPT,可以改善患者的贫血及脂质代谢紊乱,提高部分患者的透析耐受性而改善透析充分性。术前颈部甲状旁腺B超定位指导手术是可行的方法之一。避免术后复发的关键是做到真正的甲状旁腺全切除及选取适量的弥漫增生的甲状旁腺行自体前臂移植。     

Clinical study of concerning factors of decreased bone mineral content in hemodialysis patients

We investigated bone mineral content and factors related to decreased bone mineral content in maintenance hemodialysis patients. Bone mineral contents, epsilon GS/D, radius-bone mineral content (R-BMC) and L3-bone mineral density (L3-BMD), were measured with a micro densitometer, a bone mineral analyzer and a dual energy quantative CT scanner, and relative bone mineral contents (% epsilon GS/D, %R-BMC and %L3-BMD) were calculated respectively. The desferrioaxmine infusion test was carried out for diagnosis of aluminium associated bone disease, and an elevated level of aluminium (delta aluminium) was observed. There was reverse correlation between epsilon GS/D and age in female hemodialysis patients. Serum bone gla protein, alkaline phosphatase and PTH-C levels were high in cases with increased epsilon GS/D and who were receiving little medication with activated Vitamin D in maintenance hemodialysis patients. A correlation was observed between delta aluminium and total medication of aluminium hydroxide-gel. Hemodialysis patients with bone pain had long term hemodialysis, high total medication of aluminium and high aluminium. Relative bone mineral contents (% epsilon GS/D, %R-BMD) were useful for estimating bone mineral content in hemodialysis patients. Hemodialysis patients were divided in four groups by PTH-C and delta aluminium levels as follow, 1) normal, 2) aluminium associated bone disease, 3) secondary hyperparathyroidism with aluminium associated bone disease, 4) secondary hyperparathyroidism. These results indicate that secondary hyperparathyroidism, and medication with aluminium may play a role in decreased bone mineral content in hemodialysis patients, and menopause may also be an important factor in female hemodialysis patients.     

Short- and long-term outcome of total parathyroidectomy with immediate autografting versus subtotal parathyroidectomy in patients with end-stage renal disease

A retrospective study was performed in 36 patients with end-stage renal disease (ESRD) comparing total parathyroidectomy followed by immediate autografting into the forearm (total PTX + IA) with parathyroidectomy (subtotal PTX) over a five-year period. Twenty-eight patients underwent subtotal PTX and 8 had total PTX + IA. The two surgical methods were evaluated with respect to preoperative severity of hyperparathyroidism, perioperative morbidity, and the incidence of recurrent hyperparathyroidism. Eleven patients in total (30.6%) developed recurrent hyperparathyroidism; 2/8 (25%) in the total PTX + IA group compared to 9/28 (32.1%) in the subtotal PTX group (p = 0.699). The median time to recurrence was longer in the total PTX + IA group (39 vs. 16 months), and the median long-term postoperative PTH value was lower (81 vs. 199 ng/l), but these differences did not reach statistical significance. In conclusion, the incidence of recurrent hyperparathyroidism is high regardless of surgical modality. However, total PTX + IA may produce more favorable results with respect to median postoperative PTH level and time to recurrence. Copyright Copyright 1999 S. Karger AG, Basel     

IL-1beta,TNF-alpha,TGF-beta,and bFGF expression in bone biopsies before and after parathyroidectomy

BACKGROUND: There is growing evidence pointing to an involvement of cytokines and growth factors in renal osteodystrophy. In this study, the expression of interleukin-l beta (IL-1 beta), tumor necrosis factor-alpha (TNF-alpha), transforming growth factor-beta (TGF-beta), and basic fibroblast growth factor (bFGF) in bone biopsies taken from uremic patients before and 1 year after parathyroidectomy (PTX) was evaluated. Biochemical features and histomorphometric outcome were also studied. METHODS: Iliac bone biopsies were taken before and 1 year after PTX in nine uremic patients with severe hyperparathyroidism (HPT). Immunohistochemical techniques were used to identify the expression of IL-1 beta, TNF-alpha, TGF-beta, and bFGF in these bone samples. RESULTS: At the time of the second bone biopsy, the mean serum total alkaline phosphatase activity was normal, whereas mean serum intact parathyroid hormone (iPTH) level was slightly above the upper limit of normal values. Histomorphometric analysis showed a decrease in resorption parameters and static bone formation parameters after PTX. Dynamically, mineral apposition rate (MAR) and mineralization surface (MS/BS) decreased significantly. There was a marked local expression of IL-1beta, TNF-alpha, TGF-beta, and bFGF in bone biopsies before PTX, particularly in fibrous tissue and resorption areas. One year after PTX, IL-1beta decreased from 23.6 +/- 7.5% to 9.9 +/- 3.1%, TNF-alpha from 4.5 +/- 1.5% to 0.7 +/- 0.8%, TGF-beta from 49.6 +/- 9.8% to 15.2 +/- 4.6%, and bFGF from 50.9 +/- 12.7% to 12.9 +/- 7.9% (P < 0.001). A significant correlation was documented between cytokines and growth factors expression in bone with iPTH levels before and after PTX (P < 0.05). CONCLUSIONS: Based on these results, we suggest that IL-1beta, TNF-alpha, TGF-beta, and bFGF are involved in bone remodeling regulation, acting as local effectors, possibly under the control of PTH.     

Value of the 99mTc-methylene diphosphonate bone scan in renal osteodystrophy

The value of radionuclide bone scanning in the diagnosis of renal osteodystrophy is still debated. In order to re-examine this issue, 25 uremic patients treated by intermittent hemodialysis underwent 99m-Technetium Methylene Diphosphonate (99mTc-MDP) bone scan. They were subdivided into three groups according to quantitative bone histology. Group 1 (N = 8) had pure dialysis osteomalacia, group 2 (N = 7) mixed lesions, and group 3 (N = 10) pure osteitis fibrosa. The scintigraphic studies were interpreted by means of a five point semi-quantitative scale. Using this quantification, all but one group 1 patients had decreased bone tracer uptake, and all patients of group 3 had an increased uptake (chi square test of Yates, P less than 0.001). Among patients of group 2, bone uptake was decreased in the three patients with clearly reduced mineralization front and moderate osteitis fibrosa, but it was increased in all patients with severe osteitis fibrosa and subnormal mineralization front. A quantitative analysis of regional tracer uptake into bone was performed in two patients: one of group 2 and one of group 3. The results obtained clearly corroborated the semi-quantitative findings. Thus, in hemodialysis patients with symptomatic bone disease, the 99mTc-MDP bone scan provides useful information for the differential diagnosis between dialysis-related osteomalacia and secondary hyperparathyroidism. In patients with mixed lesions, the importance of bone tracer uptake appears to depend on the extent of the mineralization front and on the intensity of osteitis fibrosa.     

Indications and efficacy of parathyroidectomy in the treatment of secondary hyperparathyroidism in patients with chronic renal failure: our experience

Although secondary hyperparathyroidism is improved by pharmacological therapy; 10-30% of patients with chronic renal failure undergo parathyroidectomy. The authors report on their experience with 66 cases of secondary hyperparathyroidism surgically treated over the period from January 1991 to December 2002. The surgical indications included: persistent hypercalcaemia, osteodystrophy with bone fractures, joint pain, itching and ectopic calcifications. The median preoperative parathyroid hormone level was 400 pg/ml. The operations performed were: subtotal parathyroidectomy (PTX 7/8) in 43 cases; total parathyroidectomy with autotransplantation (PTXt + At) in 13 cases; total parathyroidectomy (PTXt) alone in 6 cases and incomplete parathyroidectomy (PTXi) in 4 cases. The immediate results were satisfactory in each group. Calcium levels reverted to normal 24-48 hours postoperatively in 37 patients with PTX 7/8, in 11 patients with PTXt + At, in 5 patients with PTXt; 4 patients with PTXi showed a reduction, but no normalization, of calcium levels. Almost all patients, except those undergoing PTXi, showed an acceptable reduction in PTH levels in 25-35 days. Secondary hyperparathyroidism relapsed in 3 cases with PTXt + At and in 2 cases with PTX 7/8, while it proved persistent in 50% of patients with PTXi and in 7% of patients with PTX 7/8. Patients with PTXt mainly showed a substantial reduction of calcium levels. Parathyroidectomy is indispensable for the treatment of secondary hyper-parathyroidism. In our opinion, PTX 7/8 is the surgical treatment of choice because it is the easiest technique to perform and has the lowest relapse rate.     

A multicenter study on the effects of lanthanum carbonate (Fosrenol) and calcium carbonate on renal bone disease in dialysis patients

BACKGROUND: Lanthanum carbonate (LC) (Fosrenol) is a novel new treatment for hyperphosphatemia. In this phase III, open-label study, we compared the effects of LC and calcium carbonate (CC) on the evolution of renal osteodystrophy (ROD) in dialysis patients. METHODS: Ninety-eight patients were randomized to LC (N = 49) or CC (N = 49). Bone biopsies were taken at baseline and after one year of treatment. Acceptable paired biopsies were available for static and dynamic histomorphometry studies in 33 LC and 30 CC patients. Blood samples were taken at regular intervals for biochemical analysis and adverse events were monitored. RESULTS: LC was well tolerated and serum phosphate levels were well controlled in both treatment groups. The incidence of hypercalcemia was lower in the LC group (6% vs. 49% for CC). At baseline, subtypes of ROD were similarly distributed in both groups, with mixed ROD being most common. At one-year follow-up in the LC group, 5 of 7 patients with baseline low bone turnover (either adynamic bone or osteomalacia), and 4 of 5 patients with baseline hyperparathyroidism, had evolved toward a normalization of their bone turnover. Only one lanthanum-treated patient evolved toward adynamic bone compared with 6 patients in the CC group. In the LC group, the number of patients having either adynamic bone, osteomalacia, or hyperpara decreased overall from 12 (36%) at baseline to 6 (18%), while in the calcium group, the number of patients with these types of ROD increased from 13 (43%) to 16 (53%). CONCLUSION: LC is a poorly absorbed, well-tolerated, and efficient phosphate binder. LC-treated dialysis patients show almost no evolution toward low bone turnover over one year (unlike CC-treated patients), nor do they experience any aluminum-like effects on bone.     

甲状旁腺切除术对血液透析患者合并继发性甲状旁腺功能亢进骨代谢及骨密度的影响

目的 观察甲状旁腺切除术(parathyroidectomy,PTX)对继发性甲状旁腺功能亢进(secondary hyperparathyroidism,SHPT)的维持性血液透析患者骨代谢及骨密度(BMD)的影响.方法 26例SHPT患者行PTX.术前及术后1、3、6、12、18、24个月时常规检测血钙、血磷、血清碱性磷酸酶,化学发光法检测血清全段甲状旁腺素(intact parathyroid,iPTH)、骨钙素(OC)、Ⅰ型前胶原氨基末端前肽(PINP)、β胶原蛋白(β-C TX),术前及术后24个月时双能X线法测定腰椎、股骨颈、骨盆各部位骨密度,观察患者甲状旁腺切除术前、术后骨代谢指标及骨密度变化.结果 (1)与术前比较,血清OC水平[(104.49±25.42) μg/L比(695.46±355.62) μg/L,P＜ 0.01]、PINP水平[(248.36±159.38) μg/L比(809.28±283.50) μg/L,P＜0.01]于手术3个月后明显降低,β-CTX水平于手术1个月后明显降低[(1.60±0.64) μg/L比(3.37±1.34) μg/L,P＜0.01].(2)与术前比较,术后24个月时腰椎BMD[(0.88±0.23) g/cm2比(0.78±0.23) g/cm2,P＜0.01]、股骨颈BMD[(0.96±0.19) g/cm2比(0.84±0.24) g/cm2,P＜ 0.01]及腰椎Z评分[(-1.24±0.55)比(-1.66±0.24),P＜0.01]、股骨颈Z评分[(-1.51±0.72)比(-1.93±0.40),P＜0.01]均升高.(3)相关分析显示,术前血清iPTH水平与⊿腰椎Z评分(r=0.584,P=0.002)、⊿股骨颈Z评分(r=0.400,P=0.043)呈正相关,术前血清OC水平与⊿腰椎Z评分(r=0.651,P＜0.001)、⊿股骨颈Z评分(r=0.509,P=0.008)呈正相关.结论 PTX术可以降低患者升高的iPTH、OC、PINP及β-CTX水平,增加骨密度,同时改善多项生化指标,提高患者生活质量.     

Studies of bone morphology, bone densitometry and laboratory data in patients on maintenance hemodialysis treatment

Bone morphological parameters of renal osteodystrophy such as abundance of osteoid surface, osteoid seam width index, calcification fronts, osteoclast activity and trabecular bone volume were studied in 71 patients on maintenance hemodialysis and compared with bone densitometry, laboratory and clinical data. Increased osteoclast activity (hyperparathyroidism) was by far the most common bone morphological finding. Patients with chronic pyelonephritis or polycystic kidney disease had more than double the amount of osteoid than patients with chronic glomerulonephritis. The trabecular bone volume seemed to be increased in most patients in contrast to the cortical bone volume which was decreased, judged from bone densitometry and previously from X-ray. Despite that patients with polycystic kidney disease were older, their trabecular volume was larger than in patients with glomerulonephritis. The bone mineral content evaluated by bone densitometry was low in most patients, and more associated with bone morphological signs of osteomalacia than with secondary hyperparathyroidism. Serum phosphate (S-PO4) and serum parathyroid hormone (S-PTH) seemed to discriminate better between osteomalacia and secondary hyperparathyroidism than serum alkaline phosphatase (S-Alk. phosph.), which was elevated in both groups. Patients who had been bilaterally nephrectomized were no more abnormal than other patients, and they had lower S-Alk. phosph. The abundance of osteoclasts was found to be a predictor of future development of clinical secondary hyperparathyroidism.     

Total Parathyroidectomy Without Autotransplantation for Renal Hyperparathyroidism: Experience with a qPTH-controlled Protocol

Background Controversy regarding the optimal surgical treatment for secondary hyperparathyroidism (sHPT) continues. Subtotal parathyroidectomy (PTX) with a small remnant and total parathyroidectomy with autotransplantation prevail, although impaired by considerable recurrence rates. Concerns about postoperative management and long-term supplementation prevent broader acceptance of total parathyroidectomy without autotransplantation. Materials and Methods The standardized surgical procedure with intraoperative PTH assessment (qPTH) included cervical thymectomy, histological proof of four parathyroid specimens and obligatory cryopreservation of parathyroid tissue in all 23 patients undergoing total PTX without autotransplantation. Whenever qPTH did not normalize, complete cervical exploration of ectopic sites was performed. Another 64 patients with subtotal PTX for sHPT served as comparison for the postoperative course. Results There were 13 primary and 10 completion (5 persistent, 5 recurrent sHPT) total PTX with 14 concurrent thyroid resections performed. Mean preoperative PTH was 1.351 pg/ml (12–72 pg/ml) and serum calcium was 2.5 mmol/l (2.25–2.5 mmol/l). PTH showed intraoperative normalization in 15 patients and a 50% PTH reduction from preoperative values in all. Postoperative course was not significantly different from the subtotal PTX group and showed PTH within the normal range for 5 patients (4 < 35 pg/ml), 7 with PTH < 12 pg/ml, and 4 without measurable PTH. In 4 patients PTH did not normalize postoperatively. Serum calcium levels were below normal in all patients: < 2.25 mmol/l in 9, < 2.00 mmol/l in 7, and <1.8 mmol/l in 6 patients. Only 1 patient required intermittent early postoperative i.v. calcium supplementation, 6 patients received oral calcium and vitamin D supplement for low calcium levels, but no severe hypocalcemic symptoms were encountered. Mean postoperative hospital stay was 5 days. No recurrent laryngeal nerve palsies were encountered. Complications were two cervical bleedings following postoperative hemodialysis requiring evacuation. Conclusions Total PTX without autotransplantation proves to be an equally safe and successful procedure for sHPT as subtotal PTX or total PTX with autotransplantation. Measurable PTH after total PTX as demonstrated in this study, supports the idea of uncontrollable isolated cell nests that are inevitably prone to stimulated growth with time. Therefore, total PTX is superior with regard to prevention of recurrence. Adequate supplementation with calcium and vitamin D, often necessary after subtotal PTX to suppress inadequate PTH and protect from recurrence, will prevent severe hypocalcemia and with the modern aluminium-diminishing dialysis regimen, development of adynamic bone disease appears less likely than feared. If necessary, cryopreserved parathyroid tissue can be autotransplanted on demand.     

Survival following parathyroidectomy among United States dialysis patients

BACKGROUND: Secondary hyperparathyroidism (SHPTH) is highly prevalent among persons with end-stage renal disease (ESRD). SHPTH has been linked to uremic bone disease, vascular calcification, and a higher risk of death. Parathyroidectomy (PTX) can dramatically reduce parathyroid hormone (PTH) and phosphate levels; however, the relationship between PTX and survival is not known. METHODS: We conducted an observational matched cohort study utilizing data from the United States Renal Database System (USRDS) in which 4558 patients undergoing a first PTX while on hemodialysis or peritoneal dialysis were individually matched by age, race, gender, cause of ESRD, dialysis duration, prior transplantation status, and dialysis modality to 4558 control patients who did not undergo PTX. Patients were followed from the date of PTX until they died or were lost to follow-up. RESULTS: The 30-day postoperative mortality rate following PTX was 3.1%. Long-term relative risks of death among patients undergoing PTX were estimated to be 10% to 15% lower than those of matched control patients not undergoing surgery. Survival curves between the 2 groups crossed 587 days following PTX. Median survival was 53.4 months (95% CI: 51.2-56.4) in the PTX group, and 46.8 months (95% CI: 44.7-48.9) in the control group. CONCLUSION: PTX was associated with higher short-term, and lower long-term, mortality rates among U.S. patients receiving chronic dialysis. Measures to attenuate SHPTH may play an important role in reducing mortality among patients with end-stage renal disease.     

肾性骨病发病机制研究及进展

肾性骨病（renal osteopathy）,泛指继发于肾脏疾病的代谢性骨病,是慢性肾脏病晚期与血液透析患者的重要并发症。广义的肾性骨病是指一切和肾脏有关的骨病;狭义的肾病骨病也称肾性骨营养不良（ROD),即慢性肾脏病矿物质和骨代谢紊乱（CKD-MBD）,是慢性肾功能衰竭（CRF）时由于钙、磷及维生素D代谢障碍,继发甲状旁腺机能亢进,酸碱平衡紊乱等因素而引起的骨病。严重影响患者的生活质量。本文论述了肾性骨病的概念、肾性骨病的发病机制、肾性骨病的分型、与肾性骨病相关的分子通路、肾性骨病的治疗原则。旨在为临床肾性骨病的诊断、治疗提供参考。     

The oral 1-25 dihydroxyvitamin D3 pulse therapy in hemodialysis patients for the early treatment of secondary hyperparathyroidism]

It is said that maintenance hemodialysis patients are already suffering from secondary hyperparathyroidism (2HPT) from early stage of chronic renal failure. The treatment of 2HPT in this stage is very important for preventing renal osteodystrophy (ROD). But many long-term dialysis patients are still afflicted with ROD although vitamin D have been used for treatment. In this study, an oral administration of 1-25 (OH)2 D3 (4 micrograms) with pulse therapy twice a week at the day before hemodialysis was started for 12 weeks. The concentration of 1-25 (OH)2D3, total calcium (Ca), ionized calcium (Ca++), alkaline phosphatase (ALP) and parathyroid hormone (PHT) in serum were measured not only before and after every 2 hours of administration a day, but also for 12 weeks after that. The peak of serum 1-25 (OH)2D3 could be sufficiently elevated after 8 hours, and the slight peak of Ca++ could be seen after 8 hours as well. But the level of total calcium could not increased. Although the level of only HS-PTH has not increased after 24 hours, a significant reduction in serum level of C-PTH, intact-PTH and HS-PTH could be recognized after 12 weeks finally. This pulse therapy was effective in reducing the serum level of PTH in this early stage from beginning hemodialysis. But, it needs further studies for the standard treatment.     

Parathyroidectomy in dialysis patients: Indications,methods, and consequences

Secondary hyperparathyroidism, characterized by increased PTH synthesis and secretion, is often seen in advanced stages of chronic kidney disease. Excessive proliferation of parathyroid cells leads to the development of diffuse hyperplasia that subsequently progresses to nodular histology. Refractory hyperparathyroidism occurs when parathyroid glands fail to respond to medical therapy. Parathyroidectomy (PTX), surgical resection of parathyroid glands, is usually performed in cases of persistent serum levels of PTH above 1000 pg/mL associated with hypercalcemia or when hyperparathyroidism is refractory to conservative therapy. Parathyroidectomy can be carried out using different procedures: subtotal PTX or total PTX with or without parathyroid autotransplantation. Parathyroid surgery may have undesirable consequences due to PTH oversuppression, such as the development of adynamic bone disease; hungry bone syndrome is quite common after this surgery. However, PTX improves survival and parameters of mineral metabolism. Parathyroidectomy needs to be considered in those patients with severe hyperparathyroidism with a poor response to pharmacological treatment and with distinct undesirable effects of PTH on bone and mineral metabolism parameters.