Effects of a parathyroidectomy on the immune system and nutritional condition in chronic dialysis patients with secondary hyperparathyroidism

Hyperparathyroidism, Serum Phosphorus and Dietary Intake in Hemodialysis Patients: Is There a Novel Relationship?

The management of hyperparathyroidism (intact parathyroid hormone (iPTH) serum levels > 585 pg/mL), frequently focuses on the appropriate control of mineral and bone markers, with the decrease in serum and dietary phosphorus as two of the targets. We aimed to investigate the association between iPTH, serum phosphorus levels and dietary intake. This was a cross-sectional, multicenter, observational study with 561 patients on hemodialysis treatment. Clinical parameters, body composition and dietary intake were assessed. For the analysis, patients were divided into three groups: (a) iPTH < 130, (b) iPTH between 130 and 585 and (c) iPTH > 585 pg/mL. The association between PTH, serum phosphorus and dietary intake was analyzed using linear regression models. In the whole sample, 23.2% of patients presented an iPTH > 585 pg/mL. Patients with higher iPTH levels were those with longer HD vintage and lower ages, higher serum phosphorus, serum calcium, Ca/P product, albumin and caffeine intake, and a lower dietary intake of phosphorus, fiber, riboflavin and folate. Higher serum phosphorus predicted higher iPTH levels, even in the adjusted model. However, lower dietary phosphorus and fiber intake were predictors of higher iPTH levels, including in the adjusted model. Our results bring new data to the relationship between dietary intake and iPTH values. Despite higher serum phosphorus being observed in patients with HPTH, an opposite association was noted regarding dietary phosphate and fiber.

Parathyroidectomy and survival in a cohort of Italian dialysis patients: results of a multicenter, observational, prospective study

BACKGROUND

Severe secondary hyperparathyroidism (SHPT) is associated with mortality in end stage kidney disease (ESKD). Parathyroidectomy (PTX) becomes necessary when medical therapy fails, thus highlighting the interest to compare biochemical and clinical outcomes of patients receiving either medical treatment or surgery.

METHODS

We aimed to compare overall survival and biochemical control of hemodialysis patients with severe hyperparathyroidism, treated by surgery or medical therapy followed-up for 36 months. Inclusion criteria were age older than 18 years, renal failure requiring dialysis treatment (hemodialysis or peritoneal dialysis) and ability to sign the consent form. A control group of 418 patients treated in the same centers, who did not undergo parathyroidectomy was selected after matching for age, sex, and dialysis vintage.

RESULTS

From 82 Dialysis units in Italy, we prospectively collected data of 257 prevalent patients who underwent parathyroidectomy (age 58.2 ± 12.8 years; M/F: 44%/56%, dialysis vintage: 15.5 ± 8.4 years) and of 418 control patients who did not undergo parathyroidectomy (age 60.3 ± 14.4 years; M/F 44%/56%; dialysis vintage 11.2 ± 7.6 y). The survival rate was higher in the group that underwent parathyroidectomy (Kaplan-Meier log rank test = 0.002). Univariable analysis (HR 0.556, CI: 0.387-0.800, p = 0.002) and multivariable analysis (HR 0.671, CI:0.465-0.970, p = 0.034), identified parathyroidectomy as a protective factor of overall survival. The prevalence of patients at KDOQI targets for PTH was lower in patients who underwent parathyroidectomy compared to controls (PTX vs non-PTX: PTH < 150 pg/ml: 59% vs 21%, p = 0.001; PTH at target: 18% vs 37% p = 0.001; PTH > 300 pg/ml 23% vs 42% p = 0.001). The control group received more intensive medical treatment with higher prevalence of vitamin D (65% vs 41%, p = 0.0001), calcimimetics (34% vs 14%, p = 0.0001) and phosphate binders (77% vs 66%, p = 0.002).

CONCLUSIONS

Our data suggest that parathyroidectomy is associated with survival rate at 36 months, independently of biochemical control. Lower exposure to high PTH levels could represent an advantage in the long term.

Relationship between serum iPTH and peritonitis episodes in patients undergoing continuous ambulatory peritoneal dialysis

Background

Peritonitis is considered as one of the most serious complications that cause hospitalization in patients undergoing continuous ambulatory peritoneal dialysis (CAPD). There is limited evidence on the impact of the parathyroid hormone (PTH) on the first peritoneal dialysis (PD)-associated peritonitis episode. We aimed to investigate the influence of serum intact parathyroid hormone (iPTH) on peritonitis in patients undergoing PD.

Methods

This was a retrospective cohort study. Patients undergoing initial CAPD from a single center in China were enrolled. The baseline characteristics and clinical information were recorded. The primary outcome of interest was the occurrence of the first PD-associated peritonitis episode. Five Cox proportional hazard models were constructed in each group set. In group set 1, all participants were divided into three subgroups by tertiles of the serum concentration of iPTH; in group set 2, all participants were divided into three subgroups based on the serum concentration of iPTH with 150 pg/ml interval (<150, 150-300, and >300 pg/ml). Hazard ratios and 95% confidence intervals (CIs) were calculated for each model. The multivariate linear regression analysis elimination procedure assessed the association between the clinical characteristics at baseline and the iPTH levels. Restricted cubic spline models were constructed, and stratified analyses were also conducted.

Results

A total of 582 patients undergoing initial PD (40% women; mean age, 45.1 ± 11.5 years) from a single center in China were recruited. The median follow-up duration was 25.3 months. Multivariate Cox regression analysis showed that, in the fully adjusted model, a higher serum iPTH level (tertile 3, iPTH >300 pg/ml) was significantly associated with a higher risk of PD-associated peritonitis at 3 years [tertile 3: hazard ratio (HR) = 1.53, 95%CI = 1.03-2.55, p = 0.03; iPTH > 300 pg/ml: HR = 1.57, 95%CI = 1.08-2.27, p = 0.02]. The hazard ratio for every 100 pg/ml increase in serum iPTH level was 1.12 (95%CI = 1.05-1.20, p < 0.01) in the total cohort when treating iPTH as a continuous variable.

Conclusions

An elevated iPTH level was significantly associated with an increased risk of peritonitis in patients undergoing CAPD.

Evaluation of T helper17 as skeletal homeostasis factor in peripheral blood mononuclear cells and T helper cells of end-stage renal disease cases with impaired parathyroid hormone

BACKGROUND

Chronic renal failure is mainly connected with high and low parathyroid hormone (PTH) levels and immunological impairments. The present study aimed to evaluate T helper 17 (Th17) cells as a crucial modulator of the immune system and skeletal homeostasis in hemodialysis patients with impaired intact PTH (iPTH).

METHODS

In this research, blood samples were taken from ESRD patients with high (> 300 pg/mL), normal (150-300 pg/mL), and low (< 150 pg/mL) serum intact parathyroid hormone (iPTH( levels (n = 30 in each group). The frequency of Th17 (CD4⁺ IL17⁺) cells was evaluated by flow cytometry in each group. The expression levels of Th17 cell-related master transcription factors, cytokines in peripheral blood mononuclear cells (PBMC), and Th cells, and the level of the mentioned cytokines were determined in the supernatant of PBMCs.

RESULTS

The number of Th17 cells remarkably increased in subjects with high iPTH against low and normal iPTH. Also, RORɣt and STAT3 levels were significantly higher in high iPTH ESRD patients than in other groups in the expression of mRNA and protein levels. These findings are confirmed by evaluating the IL-17 and IL-23 in the supernatant of cultured PBMCs and isolated Th cells.

CONCLUSION

Our findings indicated that increased serum PTH levels in hemodialysis cases may be involved in increasing the differentiation of CD4 + cells to Th17 cells in PBMC.

Elevated parathyroid hormone one year after kidney transplantation is an independent risk factor for graft loss even without hypercalcemia

Background

Hypercalcemic hyperparathyroidism has been associated with poor outcomes after kidney transplantation (KTx). However, the clinical implications of normocalcemic hyperparathyroidism after KTx are unclear. This retrospective cohort study attempted to identify these implications.

Methods

Normocalcemic recipients who underwent KTx between 2000 and 2016 without a history of parathyroidectomy were included in the study. Those who lost their graft within 1 year posttransplant were excluded. Normocalcemia was defined as total serum calcium levels of 8.5–10.5 mg/dL, while hyperparathyroidism was defined as when intact parathyroid hormone levels exceeded 80 pg/mL. The patients were divided into two groups based on the presence of hyperparathyroidism 1 year after KTx. The primary outcome was the risk of graft loss.

Results

Among the 892 consecutive patients, 493 did not have hyperparathyroidism (HPT-free group), and 399 had normocalcemic hyperparathyroidism (NC-HPT group). Ninety-five patients lost their grafts. Death-censored graft survival after KTx was significantly lower in the NC-HPT group than in the HPT-free group (96.7% vs. 99.6% after 5 years, respectively, P < 0.001). Cox hazard analysis revealed that normocalcemic hyperparathyroidism was an independent risk factor for graft loss (P = 0.002; hazard ratio, 1.94; 95% confidence interval, 1.27–2.98).

Conclusions

Normocalcemic hyperparathyroidism 1 year after KTx was an independent risk factor for death-censored graft loss. Early intervention of elevated parathyroid hormone levels may lead to better graft outcomes, even without overt hypercalcemia.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12882-022-02840-5.

Predictors of early postoperative hypocalcemia in patients with secondary hyperparathyroidism undergoing total parathyroidectomy

OBJECTIVE

To summarize the clinical features of secondary hyperparathyroidism (SHPT) in patients with chronic renal failure and to explore the predictive factors of postoperative hypocalcemia after total parathyroidectomy in these patients.

METHODS

The clinical data of 87 patients admitted to Guangdong Electric Power Hospital from May 2013 to February 2020 were reviewed. All patients underwent total parathyroid resection and sternocleidomastoid microtransplantation. Age, sex, and the serum calcium, phosphorus, alkaline phosphatase (ALP), and intact parathyroid hormone (iPTH) concentrations were analyzed as predictive factors of postoperative hypocalcemia.

RESULTS

Bone pain was the most common clinical manifestation in this study population, and all 87 patients experienced relief from their clinical symptoms after the surgical procedure. Age and the preoperative serum calcium, ALP, and iPTH concentrations were determined to be early predictive factors of postoperative hypocalcemia.

CONCLUSIONS

Age and the preoperative calcium, ALP, and iPTH concentrations are independent risk factors for postoperative hypocalcemia in patients with SHPT and renal disease who undergo total parathyroidectomy with sternocleidomastoid microtransplantation. These factors can help identify high-risk patients who can be managed by a multidisciplinary team to improve graft survival and quality of life.

Parathyroid Hormone: A Uremic Toxin

Parathyroid hormone (PTH) has an important role in the maintenance of serum calcium levels. It activates renal 1α-hydroxylase and increases the synthesis of the active form of vitamin D (1,25[OH]₂D₃). PTH promotes calcium release from the bone and enhances tubular calcium resorption through direct action on these sites. Hallmarks of secondary hyperparathyroidism associated with chronic kidney disease (CKD) include increase in serum fibroblast growth factor 23 (FGF-23), reduction in renal 1,25[OH]₂D₃ production with a decline in its serum levels, decrease in intestinal calcium absorption, and, at later stages, hyperphosphatemia and high levels of PTH. In this paper, we aim to critically discuss severe CKD-related hyperparathyroidism, in which PTH, through calcium-dependent and -independent mechanisms, leads to harmful effects and manifestations of the uremic syndrome, such as bone loss, skin and soft tissue calcification, cardiomyopathy, immunodeficiency, impairment of erythropoiesis, increase of energy expenditure, and muscle weakness.

Multicenter study on parathyroidectomy (PTX) in Italy: preliminary results

BACKGROUND

When medical therapy is unable to achieve biochemical control of secondary hyperparathyroidism, parathyroidectomy (PTX) is indicated, fortunately in a minority of patients. Thus, data on PTX prevalence and biochemical control are limited and, in particular in Italy, date back to 1999.

METHODS

We designed a prospective, observational and multicenter study to collect data from dialysis units distributed throughout the Italian regions. Clinical data were collected with a dedicated data sheet.

RESULTS

From January to December 2010, 149 Centers serving a total of 12,515 patients provided data on 528 living PTX cases (PTX prevalence = 4.2%). Prevalence was higher in hemo- than in peritoneal dialysis (4.5 vs. 1.9%, X² = 21.52; p < 0.001), with non-significant regional differences (range 0.8-7.4%). PTX patients were younger (57.6 ± 12.5 vs. 67.1 ± 14.5 years; p < 0.001), more frequently female (56 vs. 38%, X² = 68.05, p < 0.001) and had been on dialysis for a longer time (14.63 ± 8.37 vs. 4.8 ± 6.0 years, p < 0.001) compared to the 11,987 who did not undergo neck surgery. Median time since surgery was 6.0 years (3.0-9.0; 50%, IQR). The most frequent type of surgery was subtotal PTX (sPTX = 55.0%), significantly higher than total PTX (tPTX = 38.7%) or total PTX plus auto-transplantation (aPTX = 6.3%) (X² = 5.18; Bonferroni post-hoc test, sPTX vs. tPTX + aPTX = p < 0.05). As for parathyroid hormone (PTH), calcium and phosphate control, cases targeting the KDOQI ranges were 18, 50.1 and 54.4%, respectively. The most prevalent biochemical condition was low PTH (62.7%).

CONCLUSION

PTX prevalence in Italy is stable compared to previous observations, is higher in hemodialysis than in peritoneal dialysis and results in a suboptimal biochemical control.

Biological and Clinical Effects of Calciprotein Particles on Chronic Kidney Disease-Mineral and Bone Disorder

Calciprotein particles (CPPs) are a new biological marker of chronic kidney disease-mineral and bone disorder (CKD-MBD). CPPs consist of phosphate, calcium, and some proteins, with phosphate being the major contributor to the level and biological activity of CPPs. Recent studies have shown the physiological and pathological significance of CPPs, including contributions to bone and mineral metabolism, and to tissue and organ impairments such as cardiovascular damage and inflammatory responses. These actions are well known as important aspects of CKD-MBD. Fibroblast growth factor 23 (FGF23), which is secreted from the bone as the phosphaturic hormone, is markedly elevated in CKD-MBD. Many clinical studies have shown significant relationships between the level of FGF23 and outcomes such as mortality, prevalence of cardiovascular disease, bone fracture, and levels of inflammatory markers. Basic and clinical studies have suggested that CPPs contribute to synthesis and secretion of FGF23. Surgical treatments such as renal transplantation and parathyroidectomy for patients with CKD-MBD suppress excess levels of phosphate, calcium, parathyroid hormone (PTH), and FGF23, which are related to the CPP level. Therefore, suppression of CPPs might also contribute to improved clinical outcomes after these treatments.

Impact of surgical parathyroidectomy on chronic kidney disease-mineral and bone disorder (CKD-MBD) - A systematic review and meta-analysis

For more than 6 decades, many patients with advanced chronic kidney disease (CKD) have undergone surgical parathyroidectomy (sPTX) for severe secondary hyperparathyroidism (SHPT) mainly based historical clinical practice patterns, but not on evidence of outcome.We aimed in this meta-analysis to evaluate the benefits and harms of sPTX in patients with SHPT. We searched MEDLINE (inception to October 2016), EMBASE and Cochrane Library (through Issue 10 of 12, October 2016) and website clinicaltrials.gov (October 2016) without language restriction. Eligible studies evaluated patients reduced glomerular filtration rate (GFR), below 60 mL/min/1.73 m² (CKD 3–5 stages) with hyperparathyroidism who underwent sPTX. Reviewers working independently and in duplicate extracted data and assessed the risk of bias. The final analysis included 15 cohort studies, comprising 24,048 participants. Compared with standard treatment, sPTX significantly decreased all-cause mortality (RR 0.74 [95% CI, 0.66 to 0.83]) in End Stage Kidney Disease (ESKD) patients with biochemical and / or clinical evidence of SHPT. sPTX was also associated with decreased cardiovascular mortality (RR 0.59 [95% CI, 0.46 to 0.76]) in 6 observational studies that included almost 10,000 patients. The available evidence, mostly observational, is at moderate risk of bias, and limited by indirect comparisons and inconsistency in reporting for some outcomes (eg. short term adverse events, including documented voice change or episodes of severe hypocalcaemia needing admission or long-term adverse events, including undetectable PTH levels, risk of fractures etc.). Taken together, the results of this meta-analysis would suggest a clinically significant beneficial effect of sPTX on all-cause and cardiovascular mortality in CKD patients with SHPT. However, given the observational nature of the included studies, the case for a properly conducted, independent randomised controlled trial comparing surgery with medical therapy and featuring many different outcomes from mortality to quality of life (QoL) is now very strong.

Parathyroid Nodular Hyperplasia and Responsiveness to Drug Therapy in Renal Secondary Hyperparathyroidism: An Open Question

The goal of the pharmacological therapy in secondary hyperparathyroidism (SHPT) is to reduce serum levels of parathyroid hormone and phosphorus, to correct those of calcium and vitamin D, to arrest or reverse the parathyroid hyperplasia. However, when nodular hyperplasia or an autonomous adenoma develops, surgery may be indicated. We reviewed the literature with the aim of defining if the echographic criteria predictive of unresponsiveness of SHPT to calcitriol therapy are valid also in the cinacalcet era and if drug therapy may reverse nodular hyperplasia of parathyroid gland (PTG). The responsiveness to therapy and regression of the nodular hyperplasia of PTG remains an open question in the calcimimetic era as well as the cutoff between medical and surgical therapy. Prospective studies are needed in order to clarify if an earlier use of cinacalcet in moderate SHPT might arrest the progression of parathyroid growth and stabilize SHPT.

Hyperparathyroidism of Renal Disease

Renal hyperparathyroidism (rHPT) is a common complication of chronic kidney disease characterized by elevated parathyroid hormone levels secondary to derangements in the homeostasis of calcium, phosphate, and vitamin D. Patients with rHPT experience increased rates of cardiovascular problems and bone disease. The Kidney Disease: Improving Global Outcomes guidelines recommend that screening and management of rHPT be initiated for all patients with chronic kidney disease stage 3 (estimated glomerular filtration rate, < 60 mL/min/1.73 m(2)). Since the 1990s, improving medical management with vitamin D analogs, phosphate binders, and calcimimetic drugs has expanded the treatment options for patients with rHPT, but some patients still require a parathyroidectomy to mitigate the sequelae of this challenging disease.

Long-term mortality after parathyroidectomy among chronic kidney disease patients with secondary hyperparathyroidism: a systematic review and meta-analysis

Parathyroidectomy (PTx) and medical treatments are both recommended for reducing serum intact parathyroid hormone (iPTH) and curing secondary hyperparathyroidism (sHPT) in patients with chronic kidney disease (CKD), but their therapeutic effects on long-term mortality are not well-known. Thus, we aim to assess such therapeutic effect of PTx. Electronic literatures published on Pubmed, Embase, and Cochrane Central Register of Controlled Trials in any language until 27 November 2015 were systematically searched. All literatures that compared outcomes (survival rate or mortality rate) between PTx-treated and medically-treated CKD patients with sHPT were included. Finally, 13 cohort studies involving 22053 patients were included. Data were extracted from all included literatures in a standard form. The outcomes of all-cause and cardiovascular mortalities were assessed using DerSimonian and Laird's random effects model. We find PTx-treated versus medically-treated patients had a 28% reduction in all-cause mortality and a 37% reduction in cardiovascular mortality. Thus, PTx versus medical treatments might reduce the risks of all-cause and cardiovascular mortalities in CKD patients with sHPT. Further studies with prospective and large-sample clinical trials are needed to find out the real effect of PTx and to assess whether mortality rates differ among patterns of PTx.

Parathyroidectomy and survival among Japanese hemodialysis patients with secondary hyperparathyroidism

Parathyroidectomy (PTx) drastically improves biochemical parameters and clinical symptoms related to severe secondary hyperparathyroidism (SHPT) but the effect of PTx on survival has not been adequately investigated. Here we analyzed data on 114,064 maintenance hemodialysis patients from a nationwide registry of the Japanese Society for Dialysis Therapy to evaluate the associations of severity of SHPT and history of PTx with 1-year all-cause and cardiovascular mortality. We then compared the mortality rate between 4428 patients who had undergone PTx and 4428 propensity score-matched patients who had not despite severe SHPT. During a 1-year follow-up, 7926 patients of the entire study population died, of whom 3607 died from cardiovascular disease. Among patients without a history of PTx, severe SHPT was associated with an increased risk for all-cause and cardiovascular mortality. However, such an increased risk of mortality was not observed among patients with a history of PTx. In the propensity score-matched analysis, patients who had undergone PTx had a 34% and 41% lower risk for all-cause and cardiovascular mortality, respectively, compared to the matched controls. The survival benefit associated with PTx was robust in several sensitivity analyses and consistent across subgroups, except for those who had persistent postoperative SHPT. Thus, successful PTx may reduce the risk for all-cause and cardiovascular mortality in hemodialysis patients with severe, uncontrolled SHPT.

The relationship between secondary hyperparathyroidism and thyroid cancer in end stage renal disease: a population based cohort study

OBJECTIVES

We conducted a retrospective cohort study to investigate the risk of cancer in end stage renal disease (ESRD) patients with secondary hyperparathyroidism (HPT).

PATIENTS AND METHODS

This study investigated the elevated overall cancer risk in ESRD patients with secondary HPT in Taiwan. We used a population-based retrospective cohort consisting of original claims data of 1 million beneficiaries randomly sampled from the Taiwan National Health Insurance Research Database (NHIRD). We calculated the hazard ratios (HRs) and 95% confidence intervals (CIs) of cancer in the ESRD with secondary HPT and comparison cohorts, using the Cox proportional hazards regression model.

RESULTS

We observed that ESRD patients with secondary HPT exhibited a 10.1-fold increased risk of thyroid cancer than did ESRD patients without this parathyroid complication, after adjusting for comorbidities (95% confidence interval=1.12-91.0).

CONCLUSION

These phenomena indicate that ESRD patients with secondary HPT are at greater risk of thyroid cancer. Physicians should be alert for occult thyroid cancer in ESRD patients with secondary HPT.

Dramatic alteration of the skull in a uremic patient with leontiasis ossea

The craniofacial skeleton represents a peculiar target of hyperparathyroidism in patients with end-stage renal disease who exhibit a dramatic pattern of uremic leontiasis ossea. Scant information regarding this condition is available in the renal literature, as the extreme and typical manifestations of leontiasis ossea have been described in only a small series of patients. We herein report a case of significant amelioration of massive modification of the facial appearance of a 30-year-old uremic Chinese woman with severe skeletal deformities who underwent total parathyroidectomy with a forearm autograft concurrently with effective drug treatment. This report may shed light on how to better understand and treat this metabolic derangement.

Parathyroidectomy improves survival in patients with severe hyperparathyroidism: a comparative study

Background and objectives

Secondary hyperparathyroidism (SHPT) in CKD is associated with an increased risk for mortality, but definitive data showing that parathormone control decreases mortality is still lacking. This study aimed to compare the mortality of patients with severe SHPT submitted to parathyroidectomy(PTX) with those who did not have access to surgery.

Methods

This is a retrospective study in a cohort of 251 CKD patients with severe SHPT who were referred to a CKD-MBD Center for PTX from 2005 until 2012.

Results

Most of our patients had indication of PTX, but only 49% of them had access to this surgical procedure. After a mean follow-up of 23 months, 72 patients had died. Non-survivors were older; more often had diabetes, lower serum 25 vitamin D and mostly had not been submitted to surgery. The relative risk of death was lower in the PTX patients (0.428; 95% CI, 0.28 to 0.67; p<0.0001). After adjustments, mortality risk was dependent on age (1.04; 95% CI, 1.01 to 1.07; p = 0.002), 25 vitamin D (0.43; 95% CI, 0.24 to 0.81; p = 0.006) and no access to PTX (4.13; 95% CI, 2.16 to 7.88; p<0.0001). Results remained the same in a second model using the PTX date as the study start date for the PTX group.

Conclusions

Our data confirms the benefit of PTX on mortality in patients with severe SHPT. The high mortality encountered in our population is significant and urges the need to better treat these patients.

The surgical management of renal hyperparathyroidism

Secondary and tertiary hyperparathyroidism (HPT) develop in patients with renal failure due to a variety of mechanisms including increased phosphorus and fibroblast growth factor 23 (FGF23), and decreased calcium and 1,25-dihydroxy vitamin D levels. Patients present with various bone disorders, cardiovascular disease, and typical laboratory abnormalities. Medical treatment consists of controlling hyperphosphatemia, vitamin D/analog and calcium administration, and calcimimetic agents. Improved medical therapies have led to a decrease in the use of parathyroidectomy (PTX). The surgical indications include parathyroid hormone (PTH) levels >800 pg/ml associated with hypercalcemia and/or hyperphosphatemia despite medical therapy. Other indications include calciphylaxis, fractures, bone pain or pruritis. Transplant recipients often show decreased PTH, calcium and phosphorus levels, but some will have persistent HPT. Evidence suggests that PTX may cause deterioration in renal graft function in the short-term calling into the question the indications for PTX in these patients. Pre-operative imaging is only occasionally helpful except in re-operative PTX. Operative approaches include subtotal PTX, total PTX with or without autotransplantation, and possible thymectomy. Each approach has its proponents, advantages and disadvantages which are discussed. Intraoperative PTH monitoring has a high positive predictive value of cure but a poor negative predictive value and therefore is of limited utility. Hypocalcemia is the most common complication requiring aggressive calcium administration. Benefits of surgery may include improved survival, bone mineral density and alleviation of symptoms.

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.

Early effects of parathyroidectomy on erythropoietin production in secondary hyperparathyroidism

BACKGROUND

Secondary hyperparathyroidism (2-HPT) has an adverse effect on renal anemia and may cause a hyporesponsiveness to recombinant human erythropoietin (rHuEpo) in patients with chronic renal failure. The early effects of parathyroidectomy (PTx) on renal anemia, erythropoietin production, and nutritional state were examined.

METHODS

Twenty-nine patients under hemodialysis therapy received a PTx for 2-HPT. They were prospectively studied regarding hematological parameters, rHuEpo use, plasma erythropoietin levels, and nutritional condition until 12 months after PTx.

RESULTS

The hemoglobin level showed a significant increase from 3 months after PTx (10.2% +/- 1.5% to 11.2% +/- 1.3%; P <0.01), associated with a consistent increase of the reticulocyte count. These changes lasted until 12 months after PTx. The plasma erythropoietin level showed a gradual increase of up to about 5 times the level of the preoperative value, until 12 months after PTx (22.6 +/- 10.1 to 106.3 +/- 112.1 mU/mL; P <0.001). The weekly dose of rHuEpo administration decreased after 3 months. The serum levels of albumin and total protein also significantly and gradually improved until 12 months after PTx.

CONCLUSIONS

PTx caused a significant early improvement in renal anemia in patients with secondary hyperparathyroidism. This effect may be caused by an enhanced erythropoietin production and may also be partially due to the improved nutritional state after PTx.