Parathyroidectomy for tertiary hyperparathyroidism: A systematic review

Intraoperative Parathyroid Hormone Monitoring Criteria in Primary Hyperparathyroidism: A Network Meta-Analysis of Diagnostic Test Accuracy

Importance

Intraoperative parathyroid hormone (IOPTH) monitoring is recommended by the American Association of Endocrine Surgeons for use during parathyroidectomy for patients with primary hyperparathyroidism (PHPT), but there is no clinician consensus regarding the IOPTH monitoring criteria that optimize diagnostic accuracy.

Objective

To evaluate and rank the diagnostic properties of IOPTH monitoring criteria used during surgery for patients with PHPT.

Data Sources

A bayesian diagnostic test accuracy network meta-analysis (DTA-NMA) was performed, in which peer-reviewed citations from January 1, 1990, to July 22, 2023, were searched for in MEDLINE, Embase, Web of Science, CENTRAL, and CINAHL.

Study Selection

All full-text study designs that evaluated any IOPTH monitoring criteria as a diagnostic test were included in this meta-analysis. Any studies evaluating adult patients diagnosed with PHPT undergoing parathyroidectomy were also included. The reference standard used in this study was normalization of calcium and/or parathyroid hormone levels within 1 year of surgery.

Data Extraction and Synthesis

This DTA-NMA was reported in accordance with the applicable Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) reporting guidelines. Two reviewers evaluated all abstracts and full-text articles using a piloted extraction form. A third author resolved any conflicts. There are no published Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) resources for DTA-NMA. The following conventional monitoring criteria were included: Halle, Miami, Rome, Vienna, and PTH normalization, and the following modified criteria were included: Miami and PTH normalization, modified Miami, and modified Vienna. A bayesian hierarchical DTA-NMA model with corresponding 95% credible intervals (CrIs) was used to describe the pooled diagnostic characteristics of the evaluated IOPTH monitoring criteria.

Main Outcomes and Measures

Main outcomes included pooled diagnostic test properties, including sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, and diagnostic odds ratio.

Results

A total of 72 studies, which included 19 072 patients, met the inclusion criteria. Sixty-nine studies (95.8%) investigated classic PHPT. In PHPT, the Miami criteria were investigated most often and had the best diagnostic properties (diagnostic odds ratio, 60.00 [95% CrI, 32.00-145.00]) when compared to other conventional criteria. Moreover, the modified Miami criteria, which measures a postexcision IOPTH level 15 minutes or more postexcision of all hyperfunctioning parathyroid tissue, were the overall best criteria (diagnostic odds ratio, 79.71 [95% CrI, 22.46-816.67]). There was a low risk of study bias and no publication bias.

Conclusions and Relevance

The results of this meta-analysis suggest that surgeons should use the modified Miami criteria when performing IOPTH-guided surgery for patients with PHPT because these criteria optimize intraoperative diagnostic accuracy by minimizing unnecessary neck exploration and revision surgery rates.

Case report: Prolonged and severe hungry bone syndrome after parathyroidectomy in X-linked hypophosphatemia

Tertiary hyperparathyroidism is characterized by hypercalcemia resulting from autonomous parathyroid hormone production and usually occurs after a prolonged period of secondary hyperparathyroidism. This condition can be a complication of X-linked hypophosphatemia (XLH), a rare genetic disease characterized by renal phosphate loss and consequent hypophosphatemia. Parathyroidectomy is considered the first-line therapy but surgical intervention can be complicated by hungry bone syndrome. A male Caucasian patient presented with XLH, diagnosed at the age of 3 years. At the age of 21, tertiary hyperparathyroidism occurred. Neck ultrasonography, neck magnetic resonance imaging, and 99Tc-sestamibi parathyroid scintigraphy revealed two hyperplastic parathyroid glands. To minimize the risk of hypercalcemia, calcimimetic therapy was initiated. After 6 months and preparation with 1,25-dihydroxy vitamin D, the patient underwent total parathyroidectomy with autotransplantation of half of a parathyroid gland into the sternocleidomastoid muscle. Histopathological examination revealed diffuse microscopical hyperplasia of the parathyroid glands. Despite oral supplementation with calcium carbonate and calcitriol, severe hypocalcemia developed on the second postoperative day, attributable to hungry bone syndrome. This finding was confirmed by an increase in bone turnover markers and a reduction in urinary calcium excretion. Hypocalcemia correction required continuous infusion of calcium gluconate for over 2 months. After approval, the patient began burosumab therapy with significant benefits. This case illustrates the complexity of treating tertiary hyperparathyroidism and mineral metabolism in patients with XLH. The hungry bone syndrome can complicate parathyroidectomy, exposing the patients to life-threatening risks. Burosumab therapy may reduce the risk of tertiary hyperparathyroidism developing in these patients.

18F-Fluorocholine-Positron Emission Tomography/Computerized Tomography (FCH PET/CT) Imaging for Detecting Abnormal Parathyroid Glands: Indication, Practice, Interpretation and Diagnostic Performance

In patients with confirmed hyperparathyroidism (HPT) scheduled for surgical treatment, the preoperatory imaging permits to optimize the operatory protocol of parathyroidectomy (PTX), in particular by selecting those patients who can benefit from minimally invasive PTX (MIPTX). The MIPTX has the merit to shorten the operative time, incision length, and to reduce the operatory risks. With preoperative localization studies, the rate of PTX failure, in particular due to nonsuspected multiglandular or ectopic disease, has been profoundly decreased. The first cases of incidental localization of abnormal parathyroid glands (PTs) on FCH PET/CTs performed for another indication were reported more than one decade ago. Since then, significant amount of data from heterogeneous series of patients consistently confirmed better diagnostic performances of FCH PET/CT (sensitivity for detection of abnormal PT 97%, range 96%-98%) in comparison with other radiopharmaceuticals, ultrasonography or 4D-CeCT in localizing hyperfunctioning parathyroid glands (HFPTGs) in case of primary HPT. Utility of FCH PET/CT in case of renal HPT has been reported in fewer series. The article discusses and summarizes the bibliographic evidence on documented indications of FCH PET/CT in patients with HPT, its safety profile, the practice of FCH PET/CT and interpretation of FCH PET/CT findings, including potential interpretation pitfalls and tips to avoid them. Our real-world experience over 12 years reinforces published evidence supporting the use of FCH PET/CT as the first-line radionuclide imaging technique in patients with all types of HPT in whom surgery is an option.

Cohort review of patients with parathyroid cancer in End Stage Renal Disease (ESRD)

BACKGROUND AND HYPOTHESIS

Parathyroid carcinoma (PTTC) is a rare malignant endocrine tumor seen in up to 1-2% of all cases of primary hyperparathyroidism. However, incidence of parathyroid carcinoma in renal hyperparathyroidism is a rare phenomenon. We aimed to evaluate the outcomes of PTTC in renal hyperparathyroidism published in the literature.

METHODS

Cohort review of parathyroid cancer cases reported in Medline (via PubMed), COCHRANE and EMBASE between the period 1985 - 2023 in patients with renal hyperparathyroidism.

RESULTS

A total of 48 patients (20 M: 28F), with a mean age of 49.8 (± 11.7 SD: range 20-75) years. Dialysis vintage was for a period of 8.9 (± 7.2; range 6 months to 40 years). The mean preoperative values were as follows: serum corrected calcium-2.87 IQR 2.56-3.01), PTH - 221.8 (IQR 86.6 -257.2 pmol/L) and serum phosphate - 2.07 (IQR 1.72-2.28) mmol/L. Preoperative imaging was in the form of ultrasound of the neck in 21 of 48 (44%), MIBI scan in 27/48 (56%), contrast enhanced computerized tomography in 14/48 (29%) and MRI neck in 1/48 (2%). The mean size of the cancer was 2.7 (± 1.35) cm and weight of the gland ranged between 0.9 to 4.98 g. 18/48 (37%) patients underwent a total parathyroidectomy and 30/48 (63%) had subtotal parathyroidectomy. En bloc excision of the tumour along with the thyroid along and central compartment lymph nodes was only performed in 12/48 (25%), of whom 9 (19%) had it performed at index surgery, whereas in the rest was done for persistent or recurrent disease. After a mean follow up of 34 months, 14 (29%) had local recurrence, 1 (2%) had distant metastasis to the skeletal system, and 12 (25%) to the lungs. Cohort mortality was 6 (13%) due to refractory hypercalcemia.

CONCLUSIONS

Parathyroid carcinoma in renal hyperparathyroidism is rare but when encountered, en bloc excision with parathyroidectomy provides the best chance of cure. Recurrences can be difficult to treat but may be needed to treat intractable hypercalcaemia.

Tertiary Hyperparathyroidism: A Case Report

Tertiary hyperparathyroidism is characterized by increased parathyroid hormone (PTH) secretion that appears after prolonged secondary hyperparathyroidism, leading to the onset of hypercalcemia. The parathyroid glands are found to undergo hyperplastic or adenomatous changes and act autonomously with increased parathormone secretion not suppressed by feedback control. This entity is commonly associated with long-term secondary hyperparathyroidism states, such as chronic kidney disease, renal transplantation, and gastrointestinal malabsorption. The authors describe the case of a 50-year-old female with a history of biliopancreatic diversion surgery, renal lithiasis with recurrent obstructive pyelonephritis, and a work accident with significant limitation of mobility. She was referred to hospital consultation for a pathological fracture of the dorsal vertebra in the context of tertiary hyperparathyroidism due to long-term gastrointestinal malabsorption.

Pre-Transplant Calcimimetic Use and Dose Information Improves the Accuracy of Prediction of Tertiary Hyperparathyroidism after Kidney Transplantation: A Retrospective Cohort Study

Tertiary hyperparathyroidism (THPT) is characterized by elevated parathyroid hormone and serum calcium levels after kidney transplantation (KTx). To ascertain whether pre-transplant calcimimetic use and dose information would improve THPT prediction accuracy, this retrospective cohort study evaluated patients who underwent KTx between 2010 and 2022. The primary outcome was the development of clinically relevant THPT. Logistic regression analysis was used to evaluate pre-transplant calcimimetic use as a determinant of THPT development. Participants were categorized into four groups according to calcimimetic dose, developing two THPT prediction models (with or without calcimimetic information). Continuous net reclassification improvement (CNRI) and integrated discrimination improvement (IDI) were calculated to assess ability to reclassify the degree of THPT risk by adding pre-transplant calcimimetic information. Of the 554 patients, 87 (15.7%) developed THPT, whereas 139 (25.1%) received pre-transplant calcimimetic treatment. Multivariate logistic regression analysis revealed that pre-transplant calcimimetic use was significantly associated with THPT development. Pre-transplant calcimimetic information significantly improved the predicted probability accuracy of THPT (CNRI and IDI were 0.91 [p < 0.001], and 0.09 [p < 0.001], respectively). The THPT prediction model including pre-transplant calcimimetic information as a predictive factor can contribute to the prevention and early treatment of THPT in the era of calcimimetics.

Sex-Stratified Predictors of Prolonged Operative Time and Hospital Admission in Outpatient Parathyroidectomy

Our retrospective database study investigates sex-stratified predictors of prolonged operative time (POT) and hospital admission following parathyroidectomy for primary hyperparathyroidism (PHPT). The 2016 to 2018 American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) was queried for patients with PHPT undergoing parathyroidectomy. Cases analyzed were all outpatient status, arrived from home, coded as non-emergent, and elective. POT was defined by the 75th percentile. Hospital admission was defined as LOS ≥ 1 day. Univariate and multivariable binary logistic regressions were utilized. Of 7442 cases satisfying inclusion criteria, the majority were female (78.0%) and White (78.5%). Median OT (IQR) for females and males was 77 (58-108) and 81 (61-109) minutes, respectively (P = 0.003). 1965 (33.9%) females and 529 (32.3%) males required hospital admission. Independent predictors of POT included ASA class III/IV (aOR 1.342, 95% CI 1.007-1.788) and obesity (aOR 1.427, 95% CI 1.095-1.860) for males (P < 0.05). Independent predictors of hospital admission included age (aOR 1.008, 95% CI 1.002-1.014), ASA class III/IV (aOR 1.490, 95% CI 1.301-1.706), obesity (aOR 1.309, 95% CI 1.151-1.489), dyspnea (aOR 1.394, 95% CI 1.041-1.865), chronic steroid use (aOR 1.674, 95% CI 1.193-2.351), and COPD (aOR 1.534, 95% CI 1.048-2.245) for females (P < 0.05); and ASA class III/IV (aOR 1.931, 95% CI 1.483-2.516) and bleeding disorder (aOR 2.752, 95% CI 1.443-5.247) for males (P < 0.005). In conclusion, predictors of POT and hospital admission following parathyroidectomy for PHPT differed by patient sex. Identifying patients at risk for POT and hospital admission may optimize healthcare resource utilization. Level of Evidence: IV.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12070-023-04444-3.

US-guided Percutaneous Radiofrequency Ablation for Secondary Hyperparathyroidism: Long-term Outcomes and Prognostic Factors

Background Although favorable outcomes have been reported with radiofrequency ablation (RFA) for secondary hyperparathyroidism (SHPT), the long-term efficacy remains insufficiently investigated. Purpose To evaluate the long-term efficacy and safety of US-guided percutaneous RFA in patients with SHPT undergoing dialysis and to identify possible predictors associated with treatment failure. Materials and Methods This retrospective study included consecutive patients with SHPT with at least one enlarged parathyroid gland accessible for RFA who were undergoing dialysis at seven tertiary centers from May 2013 to July 2022. The primary end point was the proportion of patients with parathyroid hormone (PTH) levels less than or equal to 585 pg/mL at the end of follow-up. Secondary end points were the proportion of patients with normal calcium and phosphorus levels, the technical success rate, procedure-related complications, and improvement in self-rated hyperparathyroidism-related symptoms (0-3 ranking scale). The Wilcoxon signed rank test and generalized estimating equation model were used to evaluate treatment outcomes. Univariable and multivariable regression analyses identified variables associated with treatment failure (recurrent or persistent hyperparathyroidism). Results This study included 165 patients (median age, 51 years [IQR, 44-60 years]; 92 female) and 582 glands. RFA effectively reduced PTH, calcium, and phosphorus levels, with targeted ranges achieved in 78.2% (129 of 165), 72.7% (120 of 165), and 60.0% (99 of 165) of patients, respectively, at the end of follow-up (mean, 51 months). For the RFA sessions, the technical success rate was 100% (214 of 214). Median symptom scores (ostealgia, arthralgia, pruritus) decreased (all P < .001). Regarding complications, only hypocalcemia (45.8%, 98 of 214) was common. Treatment failure occurred in 36 patients (recurrent [n = 5] or persistent [n = 31] hyperparathyroidism). The only potential independent predictor of treatment failure was having less than four treated glands (odds ratio, 17.18; 95% CI: 4.34, 67.95; P < .001). Conclusion US-guided percutaneous RFA was effective and safe in the long term as a nonsurgical alternative for patients with SHPT undergoing dialysis; the only potential independent predictor of treatment failure was a lower number (<4) of treated glands. © RSNA, 2024 Supplemental material is available for this article.

Surgical treatment of tertiary hyperparathyroidism: does one fit for all?

BACKGROUND

Tertiary hyperparathyroidism (3HPT) is defined as a condition of excessive autonomous excretion of intact parathyroid hormone (iPTH) with persistent hypercalcemia (>10.5 mg/dL) that lasts for more than 12 months after a successful kidney transplantation, in the context of a long course secondary hyperparathyroidism (2HPT). The chronic high levels of iPTH cause a worsening of graft function, accompanied by systemic symptoms of hypercalcemia. The only curative therapy is parathyroidectomy (PTX). It remains unclear whether total parathyroidectomy with autotransplantation (TPTX-AT) or subtotal parathyroidectomy (SPTX) lead to better outcomes.

AIMS

The aim of this retrospective, single-institution cohort study is to evaluate the rate of persistent or recurrent disease and postoperative calcium/iPTH disturbances in patients treated with TPTX-AT or SPTX for 3HPT.

METHODS

A single-center retrospective analysis of 3HPT patients submitted to TPTX-AT or SPTX between 2007-2020 with at least 24 months follow-up was conducted. The outcome parameters included persistence/recurrence of disease, incidence of transitory hypocalcemia, and temporary/permanent hypoparathyroidism.

RESULTS

A cohort of 52 patients was analyzed and divided in two groups: 38 (73%) were submitted for TPTX-AT, and 14 patients (27%) were submitted for SPTX. The TPTX-AT population showed lower plasmatic calcium concentrations compared with the SPTX group during the entire follow-up period (p<0.001). There were eight cases (21%) of transitory hypocalcemia in the TPTX-AT group and none in the SPTX group, with p=0.065. Two cases (5%) of temporary hypoparathyroidism occurred in the TPTX-AT group and none in the SPTX group, with p= 0.530. There were no cases of permanent hypoparathyroidism and no cases of persistent disease. No statistical difference was assessed for the recurrence of 3HPT between the TPTX-AT group and the SPTX group (N=1, 3% vs N=1, 7%) (p=0.470).

CONCLUSION

No significative difference was registered between the TPTX-AT and SPTX groups in terms of persistence/recurrence of disease, incidence of transitory hypocalcemia, and temporary/permanent hypoparathyroidism. Mean calcium levels iPTH values were statistically lower among the TPTX-AT group compared with the SPTX group while remaining always in the range of normality.

Specific genetic aberrations of parathyroid in Chinese patients with tertiary hyperparathyroidism using whole-exome sequencing

Background

Tertiary hyperparathyroidism (THPT) is a peculiar subtype of hyperparathyroidism that usually develops from chronic kidney disease (CKD) and persists even after kidney transplantation. Unlike its precursor, secondary hyperparathyroidism (SHPT), THPT is characterized by uncontrolled high levels of calcium in the blood, which suggests the monoclonal or oligoclonal proliferation of parathyroid cells. However, the molecular abnormalities leading to THPT have not yet been fully understood.

Methods

In this study, we analyzed DNA samples from hyperplastic parathyroid and corresponding blood cells of 11 patients with THPT using whole-exome sequencing (WES). We identified somatic single nucleotide variants (SNV) and insertions or deletions variants (INDEL) and performed driver mutation analysis, KEGG pathway, and GO functional enrichment analysis. To confirm the impact of selected driver mutated genes, we also tested their expression level in these samples using qRT-PCR.

Results

Following quality control and mutation filtering, we identified 17,401 mutations, comprising 6690 missense variants, 3078 frameshift variants, 2005 stop-gained variants, and 1630 synonymous variants. Copy number variants (CNV) analysis showed that chromosome 22 copy number deletion was frequently observed in 6 samples. Driver mutation analysis identified 179 statistically significant mutated genes, including recurrent missense mutations on TBX20, ATAD5, ZNF669, and NOX3 genes in 3 different patients. KEGG pathway analysis revealed two enriched pathways: non-homologous end-joining and cell cycle, with a sole gene, PRKDC, involved. GO analysis demonstrated significant enrichment of various cellular components and cytobiological processes associated with four genes, including GO items of positive regulation of developmental growth, protein ubiquitination, and positive regulation of the apoptotic process. Compared to blood samples, THPT samples exhibited lower expression levels of PRKDC, TBX20, ATAD5, and NOX3 genes. THPT samples with exon mutations had relatively lower expression levels of PRKDC, TBX20, and NOX3 genes compared to those without mutations, although the difference was not statistically significant.

Conclusion

This study provides a comprehensive landscape of the genetic characteristics of hyperplastic parathyroids in THPT, highlighting the involvement of multiple genes and pathways in the development and progression of this disease. The dominant mutations identified in our study depicted new insights into the pathogenesis and molecular characteristics of THPT.

Parathyroid Imaging

Primary hyperparathyroidism (1° HPT) is a relatively common endocrine disorder usually caused by autonomous secretion of parathormone by one or several parathyroid adenomas. 1° HPT causing hypercalcemia, kidney stones and/or osteoporosis should be treated whenever possible by parathyroidectomy. Accurate preoperative location of parathyroid adenomas is crucial for surgery planning, mostly when performing minimally invasive surgery. Cervical ultrasonography (US) is usually performed to localize parathyroid adenomas as a first intention, followed by 99mTc- sestamibi scintigraphy with SPECT/CT whenever possible. 4D-CT is a possible alternative to 99mTc- sestamibi scintigraphy. Recently, 18F-fluorocholine positron emission tomography/computed tomography (18F-FCH PET/CT) has made its way in the clinics as it is the most sensitive method for parathyroid adenoma detection. It can eventually be combined to 4D-CT to increase its diagnostic performance, although this results in higher dose exposure to the patient. Other forms of hyperparathyroidism consist in secondary (2° HPT) and tertiary hyperparathyroidism (3° HPT). As parathyroidectomy is not usually part of the management of patients with 2° HPT, parathyroid imaging is not routinely performed in these patients. In patients with 3° HPT, total or subtotal parathyroidectomy is often performed. Localization of hyperfunctional glands is an important aid to surgery planning. As 18F-FCH PET/CT is the most sensitive modality in multigland disease, it is the preferred imaging technic in 3° HPT patients, although its cost and availability may limit its widespread use in this setting.

Missed Opportunities to Diagnose and Treat Tertiary Hyperparathyroidism After Transplant

INTRODUCTION

Tertiary hyperparathyroidism (3HPT) is common after renal transplant. However, guidelines for diagnosis are not clear and few patients are treated surgically. This study aims to determine rates of diagnosis and treatment of 3HPT in renal transplant patients with hypercalcemia.

MATERIALS AND METHODS

This retrospective chart review identified all renal transplant recipients at a single tertiary care institution between 2011 and 2021. Patients with post-transplant hypercalcemia (> 10.2 mg/dL) were identified. The time in months of index hypercalcemia was noted. Measurement of parathyroid hormone (PTH) levels after index hypercalcemia was determined and noted as elevated if > 64 pg/mL at least 6 mo after transplant. Documentation of symptoms of hyperparathyroidism, a diagnosis of hyperparathyroidism in the electronic medical record, and medical or surgical management of patients with classic 3HPT (elevated calcium and PTH) were determined.

RESULTS

Of 383 renal transplant recipients, hypercalcemia was identified in 132 patients. The majority of hypercalcemic patients had PTH levels measured (127, 96.2%). PTH was elevated in 109 (82.6%). Among the 109 patients with classic 3HPT, 54 (49.5%) had a documented diagnosis of hyperparathyroidism in the electronic medical record (P = 0.01). Kidney stones or abnormal DEXA scan were present in 16 (14.7%) and 18 (16.5%), respectively. Most patients were managed non-surgically (101, 92.6%); calcimimetics were prescribed for 42 (38.5%, P = 0.01). Eight (7.3%) patients with classic 3HPT were referred to a surgeon (P = 0.35); all were initially prescribed calcimimetics (P = 0.001).

CONCLUSIONS

3HPT is underdiagnosed in patients with elevated calcium and PTH levels post-transplant. A significant percentage of these patients go without surgical referral and curative treatment.

Readability and Quality of Online Health Information Regarding Parathyroidectomy

Objective

Assessment of the readability and quality of online health information regarding parathyroidectomy.

Study Design

Cross-sectional analysis.

Setting

Websites providing patient-oriented health information regarding parathyroidectomy obtained via the Google search engine.

Methods

The top 75 Google search results for “parathyroidectomy,”“parathyroid surgery,” and “parathyroid gland removal” were reviewed. Websites were categorized by website type and country of origin. Readability was assessed by Flesch-Kincaid Grade Level and Simple Measure of Gobbledygook. Website quality was assessed per JAMA benchmark criteria and the DISCERN instrument.

Results

A total of 74 unique websites were evaluated. The mean readability of the assessed websites exceeded the recommended sixth-grade reading level on the Flesch-Kincaid Grade Level and Simple Measure of Gobbledygook (P < .001). Readability did not vary significantly by website type. Websites originating from the United Kingdom were significantly more readable than those from the United States. The majority of assessed websites were of poor quality (n = 42, 56.8%) on assessment based on the DISCERN instrument. Quality varied significantly by website category on the JAMA benchmark criteria (P < .001) and DISCERN score (P = .049) with commercial websites receiving the highest scores. DISCERN score also varied significantly by country of origin (P = .036) with UK sites receiving highest mean DISCERN scores.

Conclusion

Online health information regarding parathyroidectomy is largely of poor quality and is poorly readable for many patients. Institutions utilizing well-defined guidelines for development of patient educational resources may provide online health information of greater quality and readability.

The American Association of Endocrine Surgeons Guidelines for the Definitive Surgical Management of Secondary and Tertiary Renal Hyperparathyroidism

OBJECTIVE

To develop evidence-based recommendations for safe, effective, and appropriate treatment of secondary (SHPT) and tertiary (THPT) renal hyperparathyroidism.

BACKGROUND

Hyperparathyroidism is common among patients with chronic kidney disease, end-stage kidney disease, and kidney transplant. The surgical management of SHPT and THPT is nuanced and requires a multidisciplinary approach. There are currently no clinical practice guidelines that address the surgical treatment of SHPT and THPT.

METHODS

Medical literature was reviewed from January 1, 1985 to present January 1, 2021 by a panel of 10 experts in SHPT and THPT. Recommendations using the best available evidence was constructed. The American College of Physicians grading system was used to determine levels of evidence. Recommendations were discussed to consensus. The American Association of Endocrine Surgeons membership reviewed and commented on preliminary drafts of the content.

RESULTS

These clinical guidelines present the epidemiology and pathophysiology of SHPT and THPT and provide recommendations for work-up and management of SHPT and THPT for all involved clinicians. It outlines the preoperative, intraoperative, and postoperative management of SHPT and THPT, as well as related definitions, operative techniques, morbidity, and outcomes. Specific topics include Pathogenesis and Epidemiology, Initial Evaluation, Imaging, Preoperative and Perioperative Care, Surgical Planning and Parathyroidectomy, Adjuncts and Approaches, Outcomes, and Reoperation.

CONCLUSIONS

Evidence-based guidelines were created to assist clinicians in the optimal management of secondary and tertiary renal hyperparathyroidism.

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.

Tertiary hyperparathyroidism in patients with pseudohypoparathyroidism type 1a

Pseudohypoparathyroidism type 1a (PHP1a) is a genetic disorder caused by heterozygous loss-of-function mutations on the maternal allele of the GNAS gene. Patients with PHP1a predominantly exhibit parathyroid hormone (PTH) resistance and physical features of Albright's hereditary osteodystrophy. We report two unrelated cases with PHP1a who developed tertiary hyperparathyroidism (HPT). Molecular analyses of the GNAS gene identified a previously known heterozygous 4-bp deletion (c. 565_568delGACT) in exon 7 in case 1 and a novel heterozygous missense mutation (p.Lys233Glu) in exon 9 in case 2. Both patients developed tertiary HPT associated with hyperfunctioning parathyroid glands during long-term treatment of hypocalcemia. Case 1 had severe osteoporosis and underwent parathyroidectomy. Case 2 was asymptomatic with no evidence of bone diseases associated with tertiary HPT. PHP1a patients are at risk of developing tertiary HPT and should be treated with sufficient doses of calcium and vitamin D to achieve serum PTH levels within the mid - normal to double the upper limit of the normal range, regardless of serum calcium levels.

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Pseudohypoparathyroidism type 1a induces tertiary hyperparathyroidism.

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Tertiary hyperparathyroidism can be complicated by hungry bone syndrome.

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Serum PTH levels should be within doubled the upper limit of normal.

Impact of parathyroidectomy on kidney graft function in post-transplant tertiary hyperparathyroidism: a comparative study

PURPOSE

Parathyroidectomy to treat tertiary hyperparathyroidism (THPT) is now on a par with calcimimetic treatment. The effects of cinacalcet and parathyroidectomy on kidney transplant function remain controversial. The aim of this study was to evaluate kidney transplant function in THPT patients treated either by parathyroidectomy, cinacalcet, or not treated.

METHODS

Between 2009 and 2019, 231 patients with functional grafts presenting THPT, defined either by calcaemia superior to 2.5 mmol/L with elevated PTH level or hypercalcaemia with non-adapted PTH level 1 year after kidney transplantation, were included. Hyperparathyroid patients treated by cinacalcet and parathyroidectomy were matched for age, sex, graft rank, and baseline eGFR with cinacalcet-only and untreated patients. Conditional logistic regression models were used to compare eGFR variations 1 year after parathyroidectomy between operated patients and matched controls. Five-year survivals were compared with the Mantel-Cox test.

RESULTS

Eleven patients treated with parathyroidectomy and cinacalcet were matched with 16 patients treated by cinacalcet-only and 29 untreated patients. Demographic characteristics were comparable between groups. Estimated odds ratios for eGFR evolution in operated patients compared with cinacalcet-only and untreated patients were 0.92 [95%CI 0.83-1.02] and 0.99 [0.89-1.10] respectively, indicating no significant impairment of eGFR 1 year after surgery. Five-year allograft survival was not significantly impaired in operated patients.

CONCLUSIONS

Parathyroidectomy did not appear to substantially alter or improve graft function 1 year after surgery or 5-year allograft survival. It could be hypothesized that in addition to its known benefits, parathyroidectomy can be safely performed vis-à-vis graft function in tertiary hyperparathyroidism.

Pediatric hyperparathyroidism: review and imaging update

Hyperparathyroidism, due to increased secretion of parathyroid hormones, may be primary, secondary or tertiary. Most pediatric patients with sporadic primary hyperparathyroidism will be symptomatic, presenting with either end-organ damage or nonspecific symptoms. In younger patients with primary hyperparathyroidism, there is a higher prevalence of familial hyperparathyroidism including germline inactivating mutations of the calcium-sensing receptor genes that result in either neonatal severe hyperparathyroidism or familial hypocalciuric hypercalcemia. Parathyroid scintigraphy and ultrasound are complementary, first-line imaging modalities for localizing hyperfunctioning parathyroid glands. Second-line imaging modalities are multiphase computed tomography (CT) and magnetic resonance imaging. In pediatrics, multiphase CT protocols should be adjusted to optimize radiation dose. Although, the role of these imaging modalities is better established in preoperative localization of hyperfunctioning parathyroid glands in primary hyperparathyroidism, the same principles apply in secondary and tertiary hyperparathyroidism. In this manuscript, we will review the embryology, anatomy, pathophysiology and preoperative localization of parathyroid glands as well as several subtypes of primary familial hyperparathyroidism. While most of the recent imaging literature centers on adults, we will focus on the issues that are pertinent and applicable to pediatrics.

Parathyroid Carcinoma in the Setting of Tertiary Hyperparathyroidism: Case Report and Review of the Literature

INTRODUCTION

Parathyroid carcinoma is one of the rarest cancers in normal population, and it is extremely uncommon in the setting of tertiary hyperparathyroidism. Indeed, only 24 cases have been reported in the literature. Presentation of the Case. We report the case of parathyroid carcinoma in a 51-year-old man, with a history of end-stage renal disease due to a horseshoe kidney treated with haemodialysis since 2013. He came to our attention due to an increase in calcium and parathyroid hormone serum levels. Neck ultrasound (US) showed a solid hypodense mass, probably the right inferior parathyroid gland, with an estimated size of 25 × 15 × 13 mm; the 99mTc-sestamibi SPECT/CT scan revealed a large radiotracer activity area in the right cervical region, compatible with a hyperfunctioning right inferior parathyroid gland. So, a tertiary hyperparathyroidism diagnosis was made. In April 2018, resection of three parathyroid glands was performed. Histopathological examination demonstrated the right inferior parathyroid gland specimen to be a parathyroid carcinoma, due to the presence of multiple, full-thickness, capsular infiltration foci, and a venous vascular invasion focus. Discussion. Diagnosis of parathyroid carcinoma in tertiary hyperparathyroidism is remarkably complex because of the lack of clinical diagnostic criteria and, in many cases, is made postoperatively at histopathological examination.

CONCLUSION

To date, radical surgery represents the mainstay of treatment, with a five- and ten-year survival rates overall acceptable.

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.

Influence of Parathyroidectomy on Kidney Graft Function in Secondary and Tertiary Hyperparathyroidism

BACKGROUND

Timing of parathyroidectomy (PTX) remains controversial in candidates for kidney transplant with concomitant renal hyperparathyroidism (HPT). The aim of this retrospective study was to identify the influence of early vs late posttransplant PTX compared to pretransplant PTX on renal graft function and morbidity.

METHODS

This single-center cohort study includes 57 patients with renal HPT and kidney transplantation treated between 2007 and 2017. Ninety-six patients had surgery for renal HPT between 2007 and 2017 as a consecutive sample. Group 1 (n = 30; tertiary HPT), group 2 (n = 66; secondary HPT). Of group 1, 4 patients were excluded for PTX before and after kidney transplantation. In group 2, 20 patients were excluded since they had not undergone kidney transplantation during follow-up. Twelve patients were excluded because of short follow-up (kidney transplantation in 2018), and 3 patients were excluded because of transplant failure within 90 days. Twenty-six patients underwent posttransplant PTX (10 patients within 12 months after transplant), and 31 patients had undergone PTX prior to kidney transplantation. Graft function, serum calcium concentrations, parathyroid hormone (PTH) levels, postoperative morbidity, and 90-day mortality were recorded.

RESULTS

Median age was 53.1 years in group 1 and 49.1 years in group 2. Most patients were male (53.8% in group 1; 54.8% in group 2). Median preoperative PTH levels were significantly different with 331.6 pg/mL in group 1 and 667.5 pg/mL in group 2 (P = .003). Creatinine levels changed little from 1.4 mg/dL (range, 0.8-2.5) to 1.7 mg/dL (range, 0.7-7.3) in group 1, and no difference was seen between early or late PTX after transplantation. In group 2, creatinine levels were 8.5 mg/dL (range, 4.6-11.7) before PTX and 8.7 mg/dL (range, 5.1-11.9) after PTX. We saw no correlation between postoperative PTH and kidney function. Thirty-five patients with postoperative PTH < 15 pg/mL displayed a mean postoperative creatinine of 5.5 mg/dL (range, 4.3-6.8), similar to other patients. Both the 30-day and 90-day mortality rates were zero.

CONCLUSIONS

PTX had no negative effect on graft function, whether performed before or after (early or late) kidney transplantation. Surgical cure of renal HPT should be performed as soon as possible to prevent secondary complications and can also be safely carried out early after transplantation.

Endoscopic parathyroidectomy using a three-port submental approach

PURPOSE

The three-port submental endoscopic approach and its variations were introduced in 2016 and have been used for thyroidectomy since. However, there has been no report of this approach being used for parathyroidectomy [1, 2]. The objective of this paper was thus to report our experience using a three-port submental approach for endoscopic parathyroidectomy in challenging cases such as tertiary parathyroidism.

METHODS

We compared the outcomes before and after endoscopic removal of the parathyroid glands using a three-port submental endoscopic approach.

RESULTS

Endoscopic subtotal parathyroidectomy was performed using submental approach in five patients with tertiary hyperparathyroidism from January 2018 to June 2019. The parathyroid hormone levels of the patients dropped significantly after undergoing subtotal parathyroidectomy (mean difference 2260 pg/ml; 95% CI 1883.74 to 2636.65), as did calcium levels (mean difference 2.84 mg/dl; 95% CI 1.90 to 3.78). No major adverse events occurred in this study.

CONCLUSIONS

Submental approach parathyroidectomy allows for visualization of all parathyroid glands. Surgical scarring was minor and was hidden under the chin. The surgical outcomes were promising, and there were no major complications.

The role of 18F-FCH PET/CT in patients with uremic hyperparathyroidism compared with 99mTc-sestaMIBI SPECT/CT and ultrasonography

BACKGROUND

The aim of this study was to evaluate the diagnostic efficacy of ¹⁸F-fluorocholine (¹⁸F-FCH) PET/CT for uremic hyperparathyroidism (uHPT) compared to ^99mTc-sestaMIBI SPECT/CT and ultrasonography (US).

METHODS

A total of 17 uHPT patients with stage 5 chronic kidney disease (CKD) were prospectively enrolled. All patients underwent US, ^99mTc-sestaMIBI SPECT/CT, and ¹⁸F-FCH within 2 months and received surgical treatment. Visual and quantitative methods were used for image analyses. Intraoperative localization and postoperative histological results of the reference standard as well as the sensitivity, specificity, accuracy, positive predictive value (PPV), and negative predictive value (NPV) of the three modalities were analyzed using Pearson's χ² tests. In addition, the diagnostic efficacy of ¹⁸F-FCH PET/CT for uHPT was evaluated. The relationships between PET parameters and laboratory parameters were assessed using the Spearman correlation coefficient.

RESULTS

A total of 63 parathyroid hyperplasia lesions were resected in 17 uHPT patients, and 53 lesions were detected using ¹⁸F-FCH PET/CT with no false-positive results. The sensitivity, specificity, accuracy, PPV, and NPV were 84.13%, 100%, 86.49%, 100%, and 52.38%, respectively. In comparison, the corresponding values for ^99mTc-sestaMIBI SPECT/CT and US were 63.49%, 90.91%, 67.57%, 97.56%, and 30.30% and 61.90%, 81.82%, 64.86%, 95.12%, and 27.27%, respectively. The volume of hyper-functioning parathyroid glands was significantly different between lesions positive in ¹⁸F-FCH PET/CT and negative in ¹⁸F-FCH PET/CT (mean volume 1.36 ± 0.55 cm³ vs. 0.83 ± 0.26 cm³; P = 0.019). US misidentified intrathyroidal parathyroid hyperplasia as thyroid nodules in three patients, while ¹⁸F-FCH PET correctly identified the anatomy. No significant associations were observed between PET parameters and laboratory parameters in uHPT.

CONCLUSION

¹⁸F-FCH PET/CT was more sensitive and accurate for uHPT than ^99mTc-sestaMIBI SPECT/CT and US, and had better preoperative diagnostic efficacy, particularly for lesions diagnosed as a thyroid nodule by US.

Intraoperative Parathyroid Hormone Monitoring in Parathyroidectomy for Tertiary Hyperparathyroidism

BACKGROUND

Tertiary hyperparathyroidism (THPT) is characterized by hypercalcemia and hyperparathyroidism after renal allograft. Limited data exist regarding the use of intraoperative parathyroid hormone (IOPTH) for THPT. We examined our series of parathyroidectomies performed for THPT to determine clinical outcomes with respect to IOPTH.

MATERIALS AND METHODS

Patients who underwent parathyroidectomy for THPT (1999-2017) were identified for inclusion. Retrospective chart review was performed. Cure was defined as eucalcemia ≥6 mo after surgery. Statistical analysis was performed.

RESULTS

Of 41 patients included in the study, 41% (n = 17) were female. The median duration of dialysis before renal allograft was 34 mo (interquartile interval [IQI]:6-60). Preoperatively, the median calcium level was 10.4 mg/dL (IQI:10.0-11.2), median parathyroid hormone was 172 pg/mL (IQI:104-293), and renal function was minimally abnormal with median glomerular filtration rate 58 mL/min/1.73 m2 (IQI:49-71). At surgery, the median final IOPTH was 40 pg/mL (IQI:29-73), and median decrease in IOPTH was 78% (IQI:72-87), with 88% (n = 36) of patients demonstrating >50% decrease. Median calcium level ≥6 mo after surgery was 9.4 mg/dL (IQI:8.8-9.7), and only one patient had recurrent hypercalcemia. Failure to achieve >50% decrease in IOPTH was not significantly associated with recurrent hypercalcemia (P = 1.000). With a median follow-up time of 41 mo (IQI:25-70), only three patients had graft failure. The positive predictive value of IOPTH for cure was 89% (95% confidence interval: 0.752-0.971), with 0% negative predictive value and 87% accuracy (95% confidence interval: 0.726-0.957).

CONCLUSIONS

Subtotal parathyroidectomy is a successful operation with durable cure of THPT. IOPTH fails to predict long-term cure in THPT despite minimally abnormal renal function.

Refractory hypercalcemia due to an ectopic mediastinal parathyroid gland in a hemodialysis patient: a case report

BACKGROUND

Hypercalcemia crisis is a complex disorder rarely induced by tertiary hyperparathyroidism, which clinically presents as nonsuppressible parathyroid hyperplasia with persistent increased PTH levels and hypercalcemia. It is one of the major risk factors of morbidity and mortality in end-stage renal disease. Parathyroidectomy should be in consideration in dialysis patients with severe hyperparathyroidism who are refractory to medical therapy. The implications and consequences of it, however, are not fully understood.

CASE PRESENTATION

We present a case of a 70 year-old man disturbed by gastrointestinal manifestations due to hypercalcaemic crisis. The patient had longstanding hypercalcaemia and hyperparathyrodism refractory to calcimimetics, calcitonin, hormone and haemodialysis. A ectopic parathyroid gland in anterior mediastinum was found and elucidated by Tc-99 m scan. Futhermore, a video-assisted thoracoscopic parathyroidectomy was performed. Histologically, the tumour consisted of densely arranged chief cells immunohistochemically positive for PTH antigens. Consequently, calcium and parathormone were declining stably without any complications.

CONCLUSIONS

On account of refractory hypercalcemia and hyperparathyroidism, radionuclide scanning is useful in the diagnosis of ectopic parathyroid gland. it is of great significance for multidisciplinary therapy combing anesthesia, surgical, endocrinology and nephrology staff.

Parathyroidectomy for the treatment of hyperparathyroidism: Thirty-day morbidity and mortality

OBJECTIVES/HYPOTHESIS

Evaluate morbidity and mortality rates for patients with different levels of hyperparathyroidism (HPT) undergoing parathyroidectomy (PTX), specifically comparing primary hyperparathyroidism to secondary and tertiary hyperparathyroidism. Assess predictive factors of increased morbidity and mortality.

STUDY DESIGN

Retrospective national database review.

METHODS

Patients undergoing PTX, defined by Current Procedural Terminology codes 60500, 60502, 60505, for the treatment of HPT, were identified in the American College of Surgeons National Surgical Quality Improvement Program database between 2006 and 2014. Incidence of morbidity and mortality was calculated for primary, secondary, and tertiary HPT. A t test, analysis of variance, and χ² analyses were used to assess preoperative characteristics among the three groups.

RESULTS

A total of 21,267 patients were included in the analysis. There was an overall 7.2% morbidity and mortality rate, including 45 (0.21%) deaths, a 1.8% readmission rate, and a 1.9% reoperation rate, but morbidity and mortality rates were widely divergent when comparing primary to secondary and tertiary HPT. PTX resulted in a 4.9% morbidity and mortality rate for primary HPT (n = 14,500), 26.8% morbidity and mortality rate for secondary HPT (n = 1661), and 21.8% morbidity and mortality rate for tertiary HPT (n = 588). The primary reason for readmission was hypocalcemia (18.3%). Hematoma (7.2%) and postoperative hemorrhage (3.3%) were the two most common causes of reoperation. Elevated preoperative serum creatinine, alkaline phosphatase, and hypertension resulted in a higher rate of complications after PTX (P < .0001).

CONCLUSIONS

Although surgery for primary HPT is an extremely common and safe procedure with minimal morbidity and mortality rates, PTX for secondary and tertiary HPT has significantly higher rates of morbidity and mortality, requiring special attention in the postoperative period. Predictive factors of poor outcomes include hypertension, elevated creatinine, and elevated alkaline phosphatase.

LEVEL OF EVIDENCE

4. Laryngoscope, 128:528-533, 2018.