The refractory secondary hyperparathyroidism presenting with retro-orbital brown tumor: a case report

BACKGROUND

Tertiary hyperparathyroidism describes the autonomous and excessive secretion of parathyroid hormone (PTH) by the parathyroid glands after longstanding secondary hyperparathyroidism in chronic kidney disease. Brown tumors are a sign of uncontrolled hyperparathyroidism. In this case, we have reported a refractory and destructive hyperparathyroidism storm. Also, it presented with atypical onset and unexpected adenoma location.

CASE PRESENTATION

A 37-year-old man was diagnosed with end-stage kidney disease 22 years ago. He has been undergoing dialysis treatment since that time. Recently, he was admitted to the ophthalmology department due to the unilateral anterior bulging of the right eye and drooping of the eyelid. Magnetic resonance imaging exhibited an extraconal mass lesion located in the right orbital posterior superolateral position. Computerized tomography scans considered expansile bone lesion with peripheral calcification and originating from the sphenoid wing. The bone mass lesion was resected via craniotomy due to the compressive effect. The pathological findings were consistent with brown tumors. Plasma intact PTH level was 4557 pg/mL. The patient informed that he underwent parathyroidectomy and two leg fractures operation in a medical query. Parathyroid scintigraphy determined three distinct foci consistent with adenomas and one of them was in mediastenum. Second parathyroidectomy was recommended to the patient but the patient refused surgery. Despite his medication and dialysis regimen being revised, PTH levels were maintained at higher levels in follow-up.

CONCLUSIONS

We presented a hyperparathyroidism case that was resistant to all treatments and exhibited all the severe complications in a long-term dialysis patient. Furthermore, this case has revealed the importance and difficulty of secondary hyperparathyroidism management.

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.

Outcomes following parathyroidectomy for secondary hyperparathyroidism in patients with chronic kidney disease - a single-centre study

BACKGROUND

Surgical parathyroidectomy may be required for severe and refractory secondary hyperparathyroidism (SHPT) in patients with chronic kidney disease (CKD). Parathyroidectomy is associated with long-term survival benefit despite an increase in short-term morbidity and mortality. Global variation in practice exists, with limited Australian data on outcomes following parathyroidectomy.

METHODS

We conducted a retrospective study of patients who underwent parathyroidectomy for SHPT between January 2010 and December 2019 at a single tertiary referral centre in Melbourne, Australia. Biochemical markers and medications were assessed 12 months pre- and post-surgery. Clinical outcomes, including hospital readmission, cardiovascular events and mortality were assessed following surgery.

RESULTS

During the 10-year study period, 129 patients underwent parathyroidectomy for SHPT (mean age 50.7 ± 15 years, 109 (85%) on dialysis). Significant immediate post-operative complications were seen in eight patients (6%), requiring admission to the intensive care unit (n = 6) or return to theatre (n = 2). Within the first 6 months, 24 patients (19%) required hospital readmission. Within 12 months post-parathyroidectomy, 100 (78%) and 103 patients (80%) experienced at least one episode of hypercalcaemia (corrected calcium >2.6 mmol/L) or hypocalcaemia (corrected calcium <2.1 mmol/L) respectively. Over a 12-month period there were six deaths (5%), and eight patients (6%) experienced a major cardiovascular event.

CONCLUSION

Significant fluctuations in serum calcium levels are common post-parathyroidectomy, however long-term morbidity and mortality in our cohort were lower than previously reported, highlighting that parathyroidectomy in a carefully selected cohort is safe for severe SHPT refractory to medical treatment. This article is protected by copyright. All rights reserved.

Type of subtotal parathyroidectomy and evolution of parathyroid hormone levels in end-stage renal disease patients: a retrospective cohort study

PURPOSE

Parathyroidectomy (PTX) is performed in end-stage renal disease (ESRD) for the treatment of secondary hyperparathyroidism. Whether and how the number of glands removed affects parathyroid hormone (PTH) levels remain controversial. The objective of this study is to compare the biochemical and pharmacological evolution after subtotal PTX according to the number of glands removed in ESRD.

METHODS

This is a unicenter longitudinal retrospective cohort study of ESRD patients who have undergone PTX [< 3 glands (group 1) vs ≥ 3 glands (group 2)] from April 2006 to October 2014 at CHU de Québec, Canada. Demographic data, comorbidities, pharmacological and biochemical parameters were collected before, 3, 6, 12 and 24 months after PTX. Linear mixed model was performed to compare the biochemical and pharmacological evolution.

RESULTS

We included 37 (13 in group 1, 24 in group 2) ESRD patients with a median age of 53 (46-58) years. The population is 68% male with a median dialysis vintage of 30.7 (18.0-61.2) months. The two groups were similar in terms of demographics and comorbidities. Compared to baseline, PTH levels in groups 1 and 2 dropped significantly at 2 years (1239-361 ng/L and 1542-398 ng/L, p < 0.05) but the evolution was comparable between the two groups.

CONCLUSIONS

Our results show the efficacy of subtotal PTX in lowering PTH levels in our ESRD cohort. However, the results were not different according to the number of glands removed.

Preoperative F-18 fluorocholine PET/CT for the detection of hyperfunctioning parathyroid glands in patients with secondary or tertiary hyperparathyroidism: comparison with Tc-99m sestamibi scan and neck ultrasound

OBJECTIVES

Currently, neck ultrasound is the preferred preoperative imaging in patients with secondary/tertiary hyperparathyroidism, and the use of Tc-99m sestamibi scan is limited in these patients. We conducted this study to compare the diagnostic utilities of F-18 fluorocholine PET/CT, Tc-99m sestamibi scintigraphy, and neck ultrasound for localizing hyperfunctioning parathyroid glands in secondary/tertiary hyperparathyroidism.

METHODS

We prospectively enrolled 30 dialysis patients with a diagnosis of secondary/tertiary hyperparathyroidism; of these, 27 participants underwent all three imaging modalities, including dual-phase F-18 fluorocholine PET/CT (PET acquired 5 and 60 min after tracer injection), dual-phase Tc-99 m sestamibi SPECT/CT, and neck ultrasound. All patients underwent parathyroidectomy after imaging. We compared the lesion-based sensitivity, specificity, and accuracy of the three image tools using histopathology as the reference.

RESULTS

A total of 27 patients (107 lesions) underwent all three imaging modalities and entered the final analysis. The lesion-based sensitivities of F-18 fluorocholine PET/CT, Tc-99m sestamibi, and ultrasound were 86%, 55%, and 62%, respectively (both p < 0.001, when comparing F-18 fluorocholine PET/CT to Tc-99 m sestamibi scan and to ultrasound). F-18 fluorocholine PET/CT, Tc-99m sestamibi, and ultrasound had similar specificities of 93%, 80%, and 87%, respectively. The accuracy of F-18 fluorocholine PET/CT (87%) was significantly higher than that of Tc-99m sestamibi (59%) and ultrasound (65%) (both p < 0.001). F-18 fluorocholine PET/CT identified more hyperplastic glands than ultrasound in 52% (14/27) patients. The sensitivity of F-18 fluorocholine PET/CT reached 95% for hyperplastic parathyroid masses as low as 200 mg.

CONCLUSIONS

F-18 fluorocholine PET/CT shows superior accuracy over the conventional imaging modalities in patients with secondary or tertiary hyperparathyroidism. The combination of F-18 fluorocholine PET/CT and neck ultrasound may enable better surgical planning in these patients.

REGISTRATION IDENTIFICATION NUMBER

NCT04316845.

Long-term outcomes and management considerations after parathyroidectomy in the dialysis patient

Parathyroidectomy (PTX) remains an important intervention for dialysis patients with poorly controlled secondary hyperparathyroidism (SHPT), though there are only retrospective and observational data that show a mortality benefit to this procedure. Potential consequences that we seek to avoid after PTX include persistent or recurrent hyperparathyroidism, and parathyroid insufficiency. There is considerable subjectivity in defining and diagnosing these conditions, given that we poorly understand the optimal PTH targets (particularly post PTX) needed to maintain bone and vascular health. While lowering PTH after PTX decreases bone turnover, long-term changes in bone activity have been poorly explored. High turnover bone disease, usually present at the time a PTX is considered, often swings to a state of low turnover in the setting of sufficiently low PTH levels. It remains unclear if all low bone turnover equate with disease. However, such changes in bone turnover appear to predispose to vascular calcification, with positive calcium balance after PTX being a potential contributor. We know little of how the post-PTX state resets calcium balance, how calcium and VDRA requirements change or what kind of adjustments are needed to avoid calcium loading. The current consensus cautions against excessive reduction of PTH although there is insufficient evidence-based guidance regarding the management of chronic kidney disease - mineral bone disease (CKD-MBD) parameters in the post-PTX state. This article aims to compile existing research, provide an overview of current practice with regard to PTX and post-PTX chronic management. It highlights gaps and controversies and aims to re-orient the focus to clinically relevant contemporary priorities in CKD-MBD management after PTX.

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.

Novel insights into parathyroid hormone: report of The Parathyroid Day in Chronic Kidney Disease

Chronic kidney disease (CKD) is often associated with a mineral and bone disorder globally described as CKD-Mineral and Bone Disease (MBD), including renal osteodystrophy, the latter ranging from high bone turnover, as in case of secondary hyperparathyroidism (SHPT), to low bone turnover. The present article summarizes the important subjects that were covered during ‘The Parathyroid Day in Chronic Kidney Disease’ CME course organized in Paris in September 2017. It includes the latest insights on parathyroid gland growth, parathyroid hormone (PTH) synthesis, secretion and regulation by the calcium-sensing receptor, vitamin D receptor and fibroblast growth factor 23 (FGF23)–Klotho axis, as well as on parathyroid glands imaging. The skeletal action of PTH in early CKD stages to the steadily increasing activation of the often downregulated PTH receptor type 1 has been critically reviewed, emphasizing that therapeutic strategies to decrease PTH levels at these stages might not be recommended. The effects of PTH on the central nervous system, in particular cognitive functions, and on the cardiovascular system are revised, and the reliability and exchangeability of second- and third-generation PTH immunoassays discussed. The article also reviews the different circulating biomarkers used for the diagnosis and monitoring of CKD-MBD, including PTH and alkaline phosphatases isoforms. Moreover, it presents an update on the control of SHPT by vitamin D compounds, old and new calcimimetics, and parathyroidectomy. Finally, it covers the latest insights on the persistence and de novo occurrence of SHPT in renal transplant recipients.

Penalized estimation in latent Markov models, with application to monitoring serum calcium levels in end-stage kidney insufficiency

We introduce a penalized likelihood form for latent Markov models. We motivate its use for biomedical applications where the sample size is in the order of the tens, or at most hundreds, and there are only few repeated measures. The resulting estimates never break down, while spurious solutions are often obtained by maximizing the likelihood itself. We discuss model choice based on the Takeuchi Information Criterion. Simulations and a real-data application to monitoring serum Calcium levels in end-stage kidney disease are used for illustration.

Surgical management of secondary hyperparathyroidism in chronic kidney disease--a consensus report of the European Society of Endocrine Surgeons

BACKGROUND

Despite advances in the medical management of secondary hyperparathyroidism due to chronic renal failure and dialysis (renal hyperparathyroidism), parathyroid surgery remains an important treatment option in the spectrum of the disease. Patients with severe and complicated renal hyperparathyroidism (HPT), refractory or intolerant to medical therapy and patients with specific requirements in prospect of or excluded from renal transplantation may require parathyroidectomy for renal hyperparathyroidism.

METHODS

Present standard and actual controversial issues regarding surgical treatment of patients with hyperparathyroidism due to chronic renal failure were identified, and pertinent literature was searched and reviewed. Whenever applicable, evaluation of the level of evidence concerning diagnosis and management of renal hyperparathyroidism according to standard criteria and recommendation grading were employed. Results were discussed at the 6th Workshop of the European Society of Endocrine Surgeons entitled Hyperparathyroidism due to multiple gland disease: An evidence-based perspective.

RESULTS

Presently, literature reveals scant data, especially, no prospective randomized studies to provide sufficient levels of evidence to substantiate recommendations for surgery in renal hyperparathyroidism. Appropriate surgical management of renal hyperparathyroidism involves standard bilateral exploration with bilateral cervical thymectomy and a spectrum of four standardized types of parathyroid resection that reveal comparable outcome results with regard to levels of evidence and recommendation. Specific patient requirements may favour one over the other procedure according to individualized demands.

CONCLUSIONS

Surgery for patients with renal hyperparathyroidism in the era of calcimimetics continues to play an important role in selected patients and achieves efficient control of hyperparathyroidism. The overall success rate and long-term control of renal hyperparathyroidism and optimal handling of postoperative metabolic effects also depend on the timely indication, individually suitable type of parathyroid resection and specialized endocrine surgery.

Survival after parathyroidectomy in chronic hemodialysis patients with severe secondary hyperparathyroidism

INTRODUCTION

The life for end-stage renal disease patients has remarkably improved in the last years. Although mineral and bone disorders remain as unsolved complication, in severe secondary hyperparathyroidism (sHPT), the ultimate treatment is parathyroidectomy (PTX). It is an old treatment, but there are still insufficient data regarding survival after PTX. The study goals were to compare 2-year mortality and morbidity after PTX in surgically versus medically treated sHPT and to compare the efficacy and safety in subtotal versus total PTX in a cohort of patients receiving hemodialysis (HD).

METHODS

This prospective, longitudinal study was carried out on a cohort of chronic HD patients with severe sHPT (iPTH over 700 pg/ml). Among the overall HD population, 26 patients underwent PTX. This group was compared to a control group treated with specific drugs. Laboratory parameters, specific symptoms and mortality were registered after 24 months of follow-up for each group. The subgroups of subtotal and total PTX patients were also compared.

RESULTS

All average values of mineral markers were significantly reduced after PTX, as a proof that surgical treatment was effective. The reduction in mineral markers and the improvement in symptoms and mortality rates were similar after total and subtotal PTX. Bone pain was significantly lower in patients after PTX than in those drug treated (p = 0.0005), but not muscle weakness and itching. Survival at 2 years was better in patients surgically treated (PTX) despite significantly higher mean baseline values of iPTH, Ca and ALP compared to patients medically treated (p = 0.03).

CONCLUSIONS

We compared clinical and laboratory outcomes in HD patients with severe sHPT. Mortality, bone pain and mineral markers were improved by PTX. Total and subtotal PTX had similar clinical outcomes.

Changes in secondary hyperparathyroidism-related biochemical parameters and medication use following parathyroidectomy

BACKGROUND

Little is known about changes in parathyroid hormone (PTH), calcium and phosphorous levels after parathyroidectomy in hemodialysis patients. We studied the effects of parathyroidectomy on these biochemical values in a large cohort of patients receiving maintenance hemodialysis.

METHODS

This retrospective cohort study included patients identified in both the United States Renal Data System and the database of a large dialysis organization who underwent parathyroidectomy in 2007-09, were aged ≥ 18 years, had Medicare Parts A and B as primary payer and had received hemodialysis for ≥ 1 year pre-parathyroidectomy. Descriptive statistics were calculated for continuous variables; categorical variables were used to characterize the population and evaluate monthly laboratory and medication use; median values were calculated for laboratory measures.

RESULTS

Among 1402 parathyroidectomy patients, mean age was 48.9 years, 52.4% were males, 58.8% were African American and mean dialysis duration was 7.5 years. Median PTH levels increased over the year before parathyroidectomy from 1039 to 1661 pg/mL and decreased afterward to 98 pg/mL at 1 month; levels remained ≥ 897 pg/mL for 10% of patients. Median calcium levels fell from 9.6 mg/dL before to 7.9 mg/dL 1 month after parathyroidectomy; levels were ≤ 7.1 mg/dL for 25% and remained ≤ 7.2 mg/dL for the lowest 25% at 3 months. Median phosphorous level was 6.8 mg/dL immediately before parathyroidectomy, decreased to 3.8 mg/dL immediately after and reached 5.8 mg/dL at 1 year.

CONCLUSIONS

While PTH levels dropped after parathyroidectomy for most patients, surgery was sometimes ineffective in reducing levels and sometimes led to over-suppression. Hypocalcemia could be profound and long lasting, suggesting the need for prolonged vigilance.

Adynamic bone disease: from bone to vessels in chronic kidney disease

Adynamic bone disease (ABD) is a well-recognized clinical entity in the complex chronic kidney disease (CKD)-mineral and bone disorder. Although the combination of low intact parathyroid hormone (PTH) and low bone alkaline phosphatase levels may be suggestive of ABD, the gold standard for precise diagnosis is histomorphometric analysis of tetracycline double-labeled bone biopsies. ABD essentially is characterized by low bone turnover, low bone volume, normal mineralization, and markedly decreased cellularity with minimal or no fibrosis. ABD is increasing in prevalence relative to other forms of renal osteodystrophy, and is becoming the most frequent type of bone lesion in some series. ABD develops in situations with reduced osteoanabolic stimulation caused by oversuppression of PTH, multifactorial skeletal resistance to PTH actions in uremia, and/or dysregulation of Wnt signaling. All may contribute not only to bone disease but also to the early vascular calcification processes observed in CKD. Various risk factors have been linked to ABD, including calcium loading, ageing, diabetes, hypogonadism, parathyroidectomy, peritoneal dialysis, and antiresorptive therapies, among others. The relationship between low PTH level, ABD, increased risk fracture, and vascular calcifications may at least partially explain the association of ABD with increased mortality rates. To achieve optimal bone and cardiovascular health, attention should be focused not only on classic control of secondary hyperparathyroidism but also on prevention of ABD, especially in the steadily growing proportions of diabetic, white, and elderly patients. Overcoming the insufficient osteoanabolic stimulation in ABD is the ultimate treatment goal.

[Surgical treatment of secondary hyperparathyroidism: a systematic review of the literature]

Secondary hyperparathyroidism (HPT) has a high prevalence in renal patients. Secondary HPT results from disturbances in mineral homeostasis, particularly calcium, which stimulates the parathyroid glands, increasing the secretion of parathyroid hormone (PTH). Prolonged stimulation can lead to autonomy in parathyroid function. Initial treatment is clinical, but parathyroidectomy (PTx) may be required. PTx can be subtotal or total followed or not followed by parathyroid tissue autograft. We compared the indications and results of these strategies as shown in the literature through a systematic literature review on surgical treatment of secondary HPT presented in MedLine and LILACS from January 2008 to March 2014. The search terms were: hyperparathyroidism; secondary hyperparathyroidism; parathyroidectomy and parathyroid glands, restricted to research only in humans, articles available in electronic media, published in Portuguese, Spanish, English or French. We selected 49 articles. Subtotal and total PTx followed by parathyroid tissue autograft were the most used techniques, without consensus on the most effective surgical procedure, although there was a preference for the latter. The choice depends on surgeon's experience. There was consensus on the need to identify all parathyroid glands and cryopreservation of parathyroid tissue whenever possible to graft if hypoparathyroidism arise. Imaging studies may be useful, especially in recurrences. Alternative treatments of secondary HPT, both interventional and conservative, require further study.

Kidney Disease Improving Global Outcomes guidelines and parathyroidectomy for renal hyperparathyroidism

BACKGROUND

Patients with end-stage renal disease develop hypocalcemia, resulting in secondary hyperparathyroidism (SHPT). No clear criterions exist to aid in surgical decision making for SHPT. The 2009 Kidney Disease Improving Global Outcomes (KDIGO) guidelines provide target ranges for serum calcium, phosphate, and parathyroid hormone (PTH) levels in patients with end-stage renal disease. Parathyroidectomy can help achieve these targets. The study purpose was to examine how parathyroidectomy for SHPT impacts KDIGO targets during immediate and long-term follow-up and to evaluate KDIGO categorization with receipt of additional surgical intervention.

METHODS

A retrospective review of a prospective parathyroidectomy database was performed. Included patients had SHPT, were on dialysis, and underwent parathyroidectomy. Calcium, phosphate, and PTH values were classified as below, within, or above KDIGO targets.

RESULTS

Between 2000 and 2013, 36 patients with SHPT met criteria. Subtotal parathyroidectomy was performed in 89%, total parathyroidectomy in 11%. Follow-up time was 54 ± 7 mo. Eight patients (22%) required additional surgery. Twenty-eight patients (76%) were alive at the last follow-up. At the last-follow up, patients had phosphate (46%), and PTH (17%) above KDIGO ranges. Factors associated with reoperation were assessed. Patient PTH within or above target immediately postoperative had a higher rate of reoperation (P < 0.01). At the last follow-up, higher phosphate (P = 0.054) and PTH (P < 0.001) were associated with higher reoperation rates, but calcium (P = 0.33) was not.

CONCLUSIONS

PTH and phosphate levels above KDIGO indices were associated with additional surgical intervention. Many patients had laboratory indices above range at the last follow up, suggesting more patients had persistent or recurrent disease than those who underwent reoperation. Patients may benefit from more aggressive medical and/or surgical management.

Parathyroid scintigraphy in renal hyperparathyroidism: the added diagnostic value of SPECT and SPECT/CT

Secondary hyperparathyroidism (sHPT) is a major complication for patients with end-stage renal disease on long-term hemodialysis or peritoneal dialysis. When the disease is resistant to medical treatment, patients with severe sHPT are typically referred for parathyroidectomy (PTx), which usually improves biological parameters as well as clinical signs and symptoms. Unfortunately, early surgical failure with persistent disease may occur in 5%-10% of patients and recurrence reaches 20%-30% at 5 years. Presently, the use of parathyroid scintigraphy in sHPT is usually limited to the management of surgical failures after initial PTx. This review describes the strengths and limitations of typical (99m)Tc-sestamibi imaging protocols, and highlights the potential benefits of using parathyroid scintigraphy in the initial workup of surgical patients.

Managing serum phosphate in haemodialysis patients: time for an innovative approach?

BACKGROUND/OBJECTIVES

Hyperphosphataemia, a common biochemical abnormality in chronic kidney disease, poses significant management challenges. This study aims to determine whether the reasons for this are multifactorial; including poor dietary knowledge, poor adherence to a low phosphate diet and phosphate-binding medications and the impact of age on these parameters.

SUBJECTS/METHODS

In order to compare serum phosphate and other associated parameters to the UK Renal Association Clinical Practice Guidelines 2010 an audit and service evaluation questionnaire was carried out in May 2011 on 130 haemodialysis outpatients attending the Plymouth Dialysis Unit.

RESULTS

Fifty-three percent of patients had serum phosphate within the target range of 1.1-1.7 mmol/l, 77% and 85% had serum calcium and parathyroid hormone within target ranges, respectively. Younger patients (18-45 years) were significantly less likely to have serum phosphate within range χ(2) (2, n=124)=18.77, P<0.001. Despite better knowledge of their own phosphate levels (P=0.005), phosphorus-rich foods (P<0.001), symptoms of hyperphosphataemia (P<0.001) and increased use of Renal Patient View (P=0.002), <65 years old had significantly higher phosphate levels than those >65 years (P<0.001). No significant associations were found between phosphate control and the following factors: gender, timing of dialysis shift, years on dialysis or dialysis adequacy.

CONCLUSIONS

In this population, despite better knowledge, younger patients have worse phosphate control than older patients. Using the same dietary education techniques may not be suitable for all ages, more innovative approaches supported by skilled health professionals are needed to motivate and engage with younger patients to promote self-management and adherence.

Short- and long-term impact of subtotal parathyroidectomy on the achievement of bone and mineral parameters recommended by clinical practice guidelines in dialysis patients: a 12-year single-center experience

BACKGROUND/AIMS

The short- and long-term impact of parathyroidectomy (PTX) on the parameters of mineral bone disease in dialysis patients with severe secondary hyperparathyroidism (HPT) remains unclear.

METHODS

A retrospective chart review of 401 consecutive dialysis patients who underwent subtotal PTX by one surgeon was performed. We checked serum levels of calcium (Ca), phosphorus (P), and intact parathyroid hormone (iPTH) for 3 consecutive days, and then monthly for Ca, P, and tri-monthly for iPTH postoperatively. Patients with available laboratory data within the 1st to 6th postoperative months were included in the short-term follow-up group and those with at least 6 months available data were in the long-term follow-up one.

RESULTS

Patients (short-term group, n = 401, and long-term group, n = 94) had severely uncontrolled serum iPTH levels, Ca, P and Ca × P before PTX. In the short-term group, percentages of cases achieving K/DOQI targets for serum Ca, Ca × P, and iPTH and KDIGO ones for serum Ca, P, and iPTH after PTX, significantly improved compared with those before operation (all p < 0.05). In the long-term group (mean follow-up of 43 ± 29 months), the percentage of achieved targets for serum iPTH in both guidelines and for serum Ca and Ca × P in the K/DOQI recommendation also improved postoperatively (all p < 0.05).

CONCLUSIONS

Achievements of K/DOQI recommended values for serum Ca, Ca × P, iPTH and KDIGO recommendations for iPTH can be successfully reached by subtotal PTX in medically refractory, secondary HPT in dialysis patients both during short- and long-term follow-ups.

Achievement of the National Kidney Foundation Kidney Disease Outcomes Quality Initiative: recommended serum calcium, phosphate and parathyroid hormone values with parathyroidectomy in patients with secondary hyperparathyroidism

Purpose

The National Kidney Foundation Kidney Disease Outcomes Quality Initiative (NKF-K/DOQI) 2003 has established guidelines for the treatment of secondary hyperparathyroidism (SHPT) in patients with chronic kidney disease - minerals and bone disorder (CKD-MBD). This study evaluated parathyroidectomy in SHPT patients for the achievement of the NKF-K/DOQI-recommended values of serum calcium, phosphate, and parathyroid hormone (PTH).

Methods

Between January 2005 and December 2010, parathyroidectomy was performed as recommended by the NKF-K/DOQI guidelines in 81 patients with SHPT and CKD-MBD. Serum PTH, calcium, and phosphate levels were measured prior to and 6, 12, 36, and 60 months after parathyroidectomy.

Results

Calcium, phosphate, and PTH levels dropped shortly after parathyroidectomy; however, a slight increase showed in the long term. Calcium levels increased for up to 60 months. Phosphate and PTH levels increased for up to 36 months but tended to decrease slightly at 60 months. The mean values were within the target ranges, except for PTH at 36 months. The target parameters of serum phosphate (42.9-61.1% of patients) and serum calcium (a peak of 61.1% of patients at 36 months, but only 28.6% at 60 months) were achieved the most. Less than 34% of patients achieved the recommended range for PTH.

Conclusion

Parathyroidectomy was not an optimal procedure for achieving all the biochemical parameters recommended by the NKF-K/DOQI. Although it was helpful in attaining the recommended values for serum calcium and phosphate in SHPT patients resistant to medical therapy, the PTH levels did not fall within the recommended range.

Utilization of parathyroidectomy for secondary hyperparathyroidism in end-stage renal disease

Background

The utilization of parathyroidectomy (PTX) to manage secondary hyperparathyroidism (SHPT) refractory to medical management (MTX) in end-stage renal disease (ESRD) in the era of calcimimetics is not well known.

Methods

Adult ESRD patients receiving dialysis between August 2007 and December 2011 at our institution with an intact parathyroid hormone (iPTH) level ≥88 pmol/L for 6 months associated with hypercalcemia and/or hyperphosphatemia for at least 50% of that period were included. Baseline characteristics and iPTH, calcium, phosphorus, calcium–phosphorus product and alkaline phosphatase (ALP) at baseline, 6 and 12 months were compared between the two groups (PTX versus MTX) using the χ² and paired t-tests.

Results

Of the total population of 687 patients, 80 (11.6%) satisfied KDOQI criteria for PTX, most of whom did not receive PTX (81.2%). At baseline, PTX patients had been on dialysis longer (P = 0.001), with higher iPTH (P < 0.001), calcium (P = 0.008) and ALP (P = 0.001) and were less likely to be African-American (P = 0.007). Complete follow-up data at 6 months were available on 75 patients (PTX = 15; MTX = 60). PTX had significantly greater reduction in iPTH (93 versus 23%) and ALP (68 versus 0%) compared with MTX. Changes from baseline in calcium, phosphate or calcium–phosphorus product levels and proportion of patients achieving KDOQI target values were not significant for either intervention. Findings were consistent at 12 months.

Conclusions

A significant proportion of ESRD patients who met indications for PTX did not receive it. Additional studies are needed to understand the barriers that prevent patients from receiving PTX, thereby resulting in underutilization.

Is serum phosphorus control related to parathyroid hormone control in dialysis patients with secondary hyperparathyroidism?

BACKGROUND

Elevated serum phosphorus (P) levels have been linked to increased morbidity and mortality in dialysis patients with secondary hyperparathyroidism (SHPT) but may be difficult to control if parathyroid hormone (PTH) is persistently elevated. We conducted a post hoc analysis of data from an earlier interventional study (OPTIMA) to explore the relationship between PTH control and serum P.

METHODS

The OPTIMA study randomized dialysis patients with intact PTH (iPTH) 300-799 pg/mL to receive conventional care alone (vitamin D and/or phosphate binders [PB]; n=184) or a cinacalcet-based regimen (n=368). For patients randomized to conventional care, investigators were allowed flexibility in using a non-cinacalcet regimen (with no specific criteria for vitamin D analogue dosage) to attain KDOQI™ targets for iPTH, P, Ca and Ca x P. For those assigned to the cinacalcet-based regimen, dosages of cinacalcet, vitamin D sterols, and PB were optimized over the first 16 weeks of the study, using a predefined treatment algorithm. The present analysis examined achievement of serum P targets (≤ 4.5 and ≤ 5.5 mg/dL) in relation to achievement of iPTH ≤ 300 pg/mL during the efficacy assessment phase (EAP; weeks 17-23).

RESULTS

Patients who achieved iPTH ≤ 300 pg/mL (or a reduction of ≥ 30% from baseline) were more likely to achieve serum P targets than those who did not, regardless of treatment group. Of those who did achieve iPTH ≤ 300 pg/mL, 43% achieved P ≤ 4.5 mg/dL and 70% achieved P ≤ 5.5 mg/dL, versus 21% and 46% of those who did not achieve iPTH ≤ 300 pg/mL. Doses of PB tended to be higher in patients not achieving serum P targets. Patients receiving cinacalcet were more likely to achieve iPTH ≤ 300 pg/mL than those receiving conventional care (73% vs 23% of patients). Logistic regression analysis identified lower baseline P, no PB use at baseline and cinacalcet treatment to be predictors of achieving P ≤ 4.5 mg/dL during EAP in patients above this threshold at baseline.

CONCLUSIONS

This post hoc analysis found that control of serum P in dialysis patients was better when serum PTH levels were lowered effectively, regardless of treatment received.

TRIAL REGISTRATION

Clinicaltrials.gov identifier NCT00110890.

Parathyroidectomy for the attainment of NKF-K/DOQI™ and KDIGO recommended values for bone and mineral metabolism in dialysis patients with uncontrollable secondary hyperparathyroidism

PURPOSE

The National Kidney Foundation Kidney Disease Outcomes Quality Initiative (NKF-K/DOQI™) 2003 and Kidney Disease: Improving Global Outcomes (KDIGO) 2009 have established guidelines for the treatement of secondary hyperparathyroidism. This study evaluated the impact of parathyroidectomy to achieve recommended values for parathyroid hormone, calcium, phosphorus and CaxPO(4) product in dialysis patients with severe secondary hyperparathyroidism that is resistant to medical treatment.

METHODS

This study included 43 consecutive patients who underwent parathyroidectomy for a severe form of secondary hyperparathyroidism (SHPT) that is unresponsive to medical treatment. The serum iPTH, calcium and phosphorus levels were measured prior to surgery, every morning after surgery for 5 days and on the first, sixth and eighth postoperative months.

RESULTS

Following parathyroidectomy, a significant decline in iPTH values was observed in all patients; however, after the 8-month study period, only one of these patients achieved a serum iPTH concentration within the K/DOQI recommended target range. Unlike iPTH, targeting for calcium, phosphorus and CaxPO(4) at the last follow-up were 55.8%, 60.5% and 93%, respectively. These values indicated a significant improvement in comparison to preoperative percentages. In regards to the KDIGO recommended guidelines, the iPTH levels did not significantly change at the end of our study compared to preoperative values; however, calcium levels significantly declined and phosphorus levels significantly improved compared to preoperative values.

CONCLUSIONS

Although the majority of patients fail to reach recommended iPTH values, parathyroidectomy remains a valuable tool to attain these NKF-K/DOQI recommendations for serum calcium, phosphorus and CaxPO(4) in dialysis patients with secondary hyperparathyroidism resistant to medical therapy. Parathyroidectomy was shown to be an inadequate intervention for achieving KDIGO recommendations.

Total parathyroidectomy with forearm autotransplantation as the treatment of choice for secondary hyperparathyroidism

Chronic kidney disease-mineral and bone disease (CKD-MBD) is associated with uraemic bone disease, vascular calcification, reduced quality of life and reduced survival. This study evaluated the efficacy of parathyroidectomy (PTX) with autotransplantation in improving short-term and long-term outcomes. Dialysis patients who underwent PTX showed significantly more favourable biochemical parameters after PTX. These changes were accompanied by a lower coronary artery calcification score, reduced thickness of the intimae media and comparable bone mineral density measures compared with control dialysis patients who did not undergo PTX. Despite the risk of a substantially lower intact parathyroid hormone level postoperatively that might lead to adynamic bone disease, none of the patients reported clinical signs of this disease, such as bone pain or fractures. In conclusion, PTX with autotransplantation led to improvement of CKD-MBD so may be considered in patients with secondary hyperparathyroidism that is resistant to treatment with vitamin D analogues and calcimimetics.

Effectiveness of cinacalcet in patients with recurrent/persistent secondary hyperparathyroidism following parathyroidectomy: results of the ECHO study

BACKGROUND

Progressive secondary hyperparathyroidism (sHPT) is characterized by parathyroid gland hyperplasia which may ultimately require parathyroidectomy (PTX). Although PTX is generally a successful treatment for those patients subjected to surgery, a significant proportion develops recurrent sHPT following PTX. ECHO was a pan-European observational study which evaluated the achievement of KDOQI(TM) treatment targets with cinacalcet use in patients on dialysis. Previously published results showed that cinacalcet plus flexible vitamin D therapy lowered serum PTH, phosphorus and calcium in the clinical practice with similar efficacy as seen in phase III trials.

METHODS

This subgroup analysis of ECHO describes the real-world cinacalcet treatment effect in patients with recurrent or persistent sHPT after PTX (n = 153) compared to sHPT patients without prior history of PTX (n = 1696).

RESULTS

Both groups of patients had substantially elevated serum PTH with comparable sHPT severity at baseline. After 12 months of cinacalcet treatment, 20.3% (26/128) of patients with prior PTX and 18.2% (253/1388) of patients without prior PTX achieved serum PTH and Ca × P values within the recommended KDOQI(TM) target ranges.

CONCLUSIONS

Our data support the successful use of cinacalcet in patients with recurrent/persistent sHPT after PTX.