Standards of care for hypoparathyroidism in adults: a Canadian and International Consensus

Palopegteriparatide Treatment Improves Renal Function in Adults with Chronic Hypoparathyroidism: 1-Year Results from the Phase 3 PaTHway Trial

INTRODUCTION

Individuals with chronic hypoparathyroidism managed with conventional therapy (active vitamin D and calcium) have an increased risk for renal dysfunction versus age- and sex-matched controls. Treatments that replace the physiologic effects of parathyroid hormone (PTH) while reducing the need for conventional therapy may help prevent a decline in renal function in this population. This post hoc analysis examined the impact of palopegteriparatide treatment on renal function in adults with chronic hypoparathyroidism.

METHODS

PaTHway is a phase 3 trial of palopegteriparatide in adults with chronic hypoparathyroidism that included a randomized, double-blind, placebo-controlled 26-week period followed by an ongoing 156-week open-label extension (OLE) period. Changes in renal function over 52 weeks (26 weeks blinded + 26 weeks OLE) were assessed using estimated glomerular filtration rate (eGFR). A subgroup analysis was performed with participants stratified by baseline eGFR < 60 or ≥ 60 mL/min/1.73 m2.

RESULTS

At week 52, over 95% (78/82) of participants remained enrolled in the OLE and of those, 86% maintained normocalcemia and 95% achieved independence from conventional therapy (no active vitamin D and ≤ 600 mg/day of calcium), with none requiring active vitamin D. Treatment with palopegteriparatide over 52 weeks resulted in a mean (SD) increase in eGFR of 9.3 (11.7) mL/min/1.73 m2 from baseline (P < 0.0001) and 43% of participants had an increase ≥ 10 mL/min/1.73 m2. In participants with baseline eGFR < 60 mL/min/1.73 m2, 52 weeks of treatment with palopegteriparatide resulted in a mean (SD) increase of 11.5 (11.3) mL/min/1.73 m2 (P < 0.001). One case of nephrolithiasis was reported for a participant in the placebo group during blinded treatment; none were reported through week 52 with palopegteriparatide.

CONCLUSION

In this post hoc analysis of the PaTHway trial, palopegteriparatide treatment was associated with significantly improved eGFR at week 52 in addition to previously reported maintenance and normalization of serum and urine biochemistries. Further investigation of palopegteriparatide for the preservation of renal function in hypoparathyroidism is warranted.

TRIAL REGISTRATION

ClinicalTrials.gov NCT04701203.

New insights into the vitamin D/PTH axis in endocrine-driven metabolic bone diseases

BACKGROUND

Endocrine regulation of bone metabolisms is the focus of the "Skeletal Endocrinology" series of meetings.

AIMS

To report on the outcome of the discussion on the role of vitamin D/PTH axis in endocrine osteopathies held during the 10th Skeletal Endocrinology Meeting which took place in Stresa (Italy) in March 2023.

OUTCOMES

Vitamin D/PTH axis has relevant influence on several outcomes in the general population and in patients affected by endocrinopathies such as hypoparathyroidism and secreting pituitary adenomas.

CONCLUSIONS

Assessing the status of the vitamin D/PTH axis and using vitamin D and PTH as therapeutic agents is mandatory in several endocrine-related bone metabolic conditions.

Recombinant PTH Infusion in a Child With Sanjad-Sakati Syndrome Refractory to Conventional Therapy

Hypoparathyroidism is the most common endocrinological feature in children with Sanjad-Sakati syndrome. Treatment includes active vitamin D and calcium supplementation. Here, we report a case of a newborn with Sanjad-Sakati syndrome who had severe hypocalcemia since birth who responded to PTH subcutaneous pump infusion. The child was born at 35 weeks with hypocalcemia since the first day of life. The standard medical treatment proved ineffective for the newborn, necessitating the administration of unusually high doses of oral and IV calcium and vitamin D analogue for a 2 months. As a result, intermittent subcutaneous injections of PTH were commenced, resulting in an initial improvement in calcium levels, although this proved to be short-lived. Subsequently, a switch to continuous infusion via a Medtronic Vio pump was made, which unfortunately resulted in iatrogenic hypercalcemia, requiring management of hypercalcemia. Later, calcium carbonate and alfacalcidol were resumed at a lower dosage and continued to have average requirements for patients with hypoparathyroidism. PTH subcutaneous infusion can be highly effective in refractory hypocalcemia cases and can significantly impact the treatment course and facilitate hospital discharge as seen in our case. Careful dosage and monitoring are required to avoid iatrogenic hypercalcemia.

Open-label extension of a randomized trial investigating safety and efficacy of rhPTH(1-84) in hypoparathyroidism

Hypoparathyroidism (HypoPT) is a rare disease, often inadequately controlled by conventional treatment. PARALLAX was a mandatory post-marketing trial assessing pharmacokinetics and pharmacodynamics of different dosing regimens of recombinant human parathyroid hormone 1-84 (rhPTH[1-84]) for treating HypoPT. The present study (NCT03364738) was a phase 4, 1-yr open-label extension of PARALLAX. Patients received only 2 doses of rhPTH(1-84) in PARALLAX and were considered treatment-naive at the start of the current study. rhPTH(1-84) was initiated at 50 μg once daily, with doses adjusted based on albumin-corrected serum calcium levels. Albumin-corrected serum calcium (primary outcome measure), health-related quality of life (HRQoL), adverse events, and healthcare resource utilization (HCRU) were assessed. The mean age of the 22 patients included was 50.0 yr; 81.8% were women, and 90.9% were White. By the end of treatment (EOT), 95.5% of patients had albumin-corrected serum calcium values in the protocol-defined range of 1.88 mmol/L to the upper limit of normal. Serum phosphorus was within the healthy range, and albumin-corrected serum calcium-phosphorus product was below the upper healthy limit throughout, while mean 24-h urine calcium excretion decreased from baseline to EOT. Mean supplemental doses of calcium and active vitamin D were reduced from baseline to EOT (2402-855 mg/d and 0.8-0.2 μg/d, respectively). Mean serum bone turnover markers, bone-specific alkaline phosphatase, osteocalcin, procollagen type I N-terminal propeptide, and type I collagen C-telopeptide increased 2-5 fold from baseline to EOT. The HCRU, disease-related symptoms and impact on HRQoL improved numerically between baseline and EOT. Nine patients (40.9%) experienced treatment-related adverse events; no deaths were reported. Treatment with rhPTH(1-84) once daily for 1 yr improved HRQoL, maintained eucalcemia in 95% of patients, normalized serum phosphorus, and decreased urine calcium excretion. The effects observed on urine calcium and the safety profile are consistent with previous findings.

Clinical trial identifier

NCT03364738.

Development of a tool to calculate the probability of hypocalcemia after total thyroidectomy: a prospective study

PURPOSE

This study aimed to evaluate the ability of the percentage of decrease in serum PTH level in the first 8 h after total thyroidectomy (TT) to predict hypocalcemia requiring Ca supplementation and develop a tool to predict it.

METHODS

97 patients who underwent TT with measurement of preoperative parathyroid hormone (PTH) levels were prospectively evaluated 1 and 8 h after TT; postoperative magnesium (Mg2PO) and phosphorus levels were evaluated on the 2nd day after surgery. The percentage of decrease in PTH level 1 h (%dPTH1h) and 8 h (%dPTH8h) postoperatively and predictors of hypocalcemia requiring Ca supplementation were evaluated and an equation was developed to predict this outcome.

RESULTS

%dPTH1h (p = 0.002), %dPTH8h (p = 0.001) and (Mg2PO) (p < 0.01) were isolated predictors of postoperative hypocalcemia requiring Ca supplementation. The data obtained led to the development of two tools to predict this complication.

CONCLUSIONS

The percentage of decrease in PTH level 1 h and 8 h postoperatively and the magnesium level on the 2nd day after surgery were predictors of more severe hypocalcemia, and an auxiliary tool for predicting this complication was developed.

Dilated cardiomyopathy in patients with hypoparathyroidism: A narrative review

Background

Hypoparathyroidism is a rare endocrine disorder characterized by low blood calcium levels, elevated phosphorus levels, and insufficient parathyroid hormone production. It can lead to dilated cardiomyopathy (DCM), a cardiac condition characterized by enlarged ventricles and reduced heart function. This review aims to explore the relationship between hypoparathyroidism and DCM, the impact of calcium on cardiac function, and the potential for DCM reversal with calcium supplementation.

Methods

A comprehensive literature search was conducted using PubMed, Google Scholar, and relevant keywords and Mesh terms. Case reports evaluating dilated cardiomyopathy in patients with Hypoparathyroidism were included in the study. Additionally, references cited in each study were carefully examined to identify relevant reports. The cases included in the review were analyzed, and common cardiac manifestations, diagnostic approaches, and management were identified.

Results

DCM in hypoparathyroidism presents with symptoms of heart failure, reduced ejection fraction, and impaired left ventricular function. Laboratory tests show low serum calcium levels and elevated phosphate levels. Prompt diagnosis and treatment with calcium and vitamin D supplementation can lead to improvements in cardiac function.

Conclusion

Hypoparathyroidism-induced DCM is reversible with timely calcium and vitamin D supplementation. Patient compliance with prescribed medications and supplements is crucial to prevent and manage cardiac complications. Regular follow-up check-ups and monitoring of calcium levels can aid in early detection and improve patient outcomes. Educating patients about the importance of treatment adherence can significantly reduce the risk of developing DCM and other cardiac symptoms associated with hypoparathyroidism. Routine follow-up of DCM among patients with endocrine disorders is recommended.

The Challenge of Preoperative Panel Reactive Antibody Positivity in Parathyroid Transplantation

OBJECTIVES

Identifying suitable recipient criteria and matching recipients with appropriate donors are required to increase survival for parathyroid transplant. This study was undertaken to evaluate transplant survival rates while comparing preoperative panel reactive antibody positivity.

MATERIALS AND METHODS

The study included 14 hypoparathyroidism patients who presented to our clinic for parathyroid transplant. Preoperative ABO compatibility and negative cross-match tests were prioritized for recipient-donor matching, and panel reactive antibody screening tests were performed. During the 24-month follow-up, we evaluated medication use and serum calcium, phosphorus, and parathormone levels of patients.

RESULTS

Preoperative panel reactive antibody positivity was assessed in 3 groups. The HLA class I-positive group (mean fluorescence intensity range, 179-1770) showed decreased medication use and stability in serum calcium levels. The HLA class IIpositive (mean fluorescence intensity range, 85-3959) showed decreased medication use by 25% to 50% and returned to their former prescription doses after 12 months. An opposite pattern was observed in 2 patients with panel reactive antibody positivity for both HLA classes (mean fluorescence intensity range, 462-2289), with 1 patient requiring medication for continuing symptoms and the other patient occasionally taking additional magnesium supplementation, despite decreased medication doses after 12 months. Serum calcium levels remained normal, and parathormone and phosphorus levels were elevated.

CONCLUSIONS

Improving patient symptoms and having no requirement for intravenous calcium replacement are priorities, and monitoring serum levels is the next important step. Varied panel reactive antibody positivities and survival rates indicate a requirement, and each HLA class could require a proper limitation for the mean fluorescence intensity. Preoperative mean fluorescence intensity cut-off value should be <900. Higher mean fluorescence intensity values in panel reactive antibody screenings could increase risk of short-term graft survival after parathyroid transplant. Further studies should include immunological risk assessments by individualizing the outcome with donor-specific antibodies.

Pregnancy, delivery and neonatal outcomes among women with hypoparathyroidism-A population-based study

OBJECTIVE

Data are inconclusive regarding pregnancy complications associated with maternal chronic hypoparathyroidism. Therefore, we aimed to compare pregnancy, delivery and neonatal outcomes in patients affected by chronic hypoparathyroidism to those without chronic hypoparathyroidism.

DESIGN

A retrospective population-based study utilising data from the Healthcare Cost and Utilization Project Nationwide Inpatient Sample (HCUP-NIS) database over 11 years from 2004 to 2014 inclusively. Multivariate logistic regression was used to control for confounders.

PATIENTS

Patients with chronic hypoparathyroidism compared with those without.

MEASUREMENTS

Obstetric and neonatal outcomes.

RESULTS

We identified 204 pregnancies in mothers with chronic hypoparathyroidism and 9,096,584 pregnancies without chronic hypoparathyroidism. After adjusting for age, insurance plan type, obesity, chronic hypertension, thyroid disease, pregestational diabetes mellitus, and previous caesarean section, patients in the hypoparathyroidism group, compared with those without hypoparathyroidism, were found to have an increased rate of preterm birth (<37 weeks) (19.1% vs. 7.2%, aOR: 2.49, 95% confidence interval [CI]: 1.74-3.54, p < 0.0001, respectively); and blood transfusions (4.9% vs. 1.0%, aOR: 4.07, 95% CI: 2.15-7.73, p < -0.0001). Neonates to mothers with chronic hypoparathyroidism had a higher rate of congenital anomalies (4.4% vs. 0.4%, aOR: 6.50, 95% CI: 3.31-12.75, p < 0.0001), with comparable rates of small-for-gestational-age neonates and intrauterine foetal death.

CONCLUSION

This is the largest study of chronic hypoparathyroidism in pregnancy to date. We found significant increases in the rates of preterm birth, blood transfusions and congenital anomalies in chronic hypoparathyroidism. Our findings highlight the importance of identifying chronic hypoparathyroidism as a risk factor for pregnancy and neonatal complications, although it remains unknown if maintaining calcium in the target range will mitigate these risks.

The effects of adequate dietary calcium intake in patients with hypoparathyroidism non-adherent to treatment: a prospective randomized controlled trial

OBJECTIVE

A significant problem that compels clinicians in the conventional treatment of hypoparathyroidism is patients' non-adherence to treatment. This study aimed to evaluate the effects of adequate Ca intake with dietary recommendations among hypoparathyroidism patients who persistently use Ca supplementation irregularly on plasma Ca and phosphate levels.

METHODS

This prospective, randomized, controlled study was conducted on patients diagnosed with chronic hypoparathyroidism who persistently interrupt Ca supplementation therapy and therefore have a hypocalcemic course. Patients with a total daily Ca intake below 800 mg were randomized. All patients were advised to keep the doses of active vitamin D and Ca supplements they were currently using. The patients in the study group (n=32) were advised to consume 1,000-1,200 mg of Ca daily, and the patients in the control group (n=35) were advised to continue their diet according to their daily habits. After 12 weeks of follow-up, the patients' laboratory values were compared between groups to assess treatment goals.

RESULTS

The mean of the total Ca level was 8.56±0.36 mg/dL in the study group and was found to be significantly higher than that in the control group, which was 7.67±0.48 mg/dL (p<0.001). The mean serum phosphate and serum Ca-P product levels were significantly higher in the study group (p<0.001) but did not exceed the safe upper limits in any patient.

CONCLUSION

A suitable increase in dietary Ca intake could effectively control hypocalcemia in patients with hypoparathyroidism who persistently interrupt the recommended calcium supplementation.

Hypoparathyroidism - management, information needs, and impact on daily living from the patients' perspective: results from a population-based survey

PURPOSE

Hypoparathyriodism (hypoPT) is a rare endocrine disorder. It is not known how hypoPT is managed in Germany or whether patients have unmet information needs or impairments in their daily living.

METHODS

HypoPT patients at a minimum of 6 months' post-diagnosis were invited to participate in an online survey through their treating physician or through patient organizations. An extensive questionnaire, which was developed and pilot-tested with hypoPT patients, was administered.

RESULTS

A total of 264 patients with a mean age of 54.5 years (SD: 13.3), 85.2% female and 92% with postsurgical hypoPT, participated in the study. In total, 74% of the patients reported regular monitoring of serum calcium at least every 6 months, with lower control frequencies for phosphate (47%), magnesium (36%), creatinine (54%), and parathyroid hormone (50%), and 24-h urine calcium excretion (36%) on a yearly basis. Information on symptoms of hypo- and hypercalcemia was available in 72 and 45% of the patients. Information needs were related to the disease and its treatment as well as to nutrition, physical activities/sports, and support opportunities. Statistically significant differences for all information needs in association with symptom burden were observed. Hospitalization for hypocalcemia was reported by 32%, nutritional impairments (38%) or impact on work ability (52%) was available among patients with hypoPT.

CONCLUSION

HypoPT patients experience impairments in daily living and report unmet information needs. Patient and physician education regarding hypoPT is one of the key concepts for improving the management of patients with hypoPT.

Case Report: Calcium sensing receptor gene gain of function mutations: a case series and report of 2 novel mutations

Autosomal dominant hypocalcemia (ADH1) is a genetic disorder characterized by low serum calcium and low or inappropriately normal levels of parathyroid hormone. The disease is caused by a heterozygous activating mutation of the calcium-sensing receptor (CaSR) gene, encoding a G-Protein-coupled cell membrane sensor of extracellular calcium concentration mainly expressed by parathyroid glands, renal tubules, and the brain. ADH1 has been linked to 113 unique germline mutations, of which nearly 96% are missense mutations. There is often a lack of a clear genotype/phenotype correlation in the reported literature. Here, we described a case series of 6 unrelated ADH1 probands, each one bearing a gain-of-function CaSR mutation, and two children of one of these cases, matching our identified mutations to the same ones previously reported in the literature, and comparing the clinical and biochemical characteristics, as well as the complication profile. As a result of these genetic and clinical comparisons, we propose that a genotype/phenotype correlation may exist because our cases showed similar presentation, characteristics, and severity, with respect to published cases with the same or similar mutations. We also contend that the severity of the presentation is highly influenced by the specific CaSR variant. These findings, however, require further evaluation and assessment with a systematic review.

A Phase I Randomized Trial of Once-Daily Versus Twice-Daily Recombinant Human Parathyroid Hormone (1-84) for Hypoparathyroidism

Recombinant human parathyroid hormone (1-84), rhPTH(1-84), is an approved adjunctive treatment to oral calcium and active vitamin D for adult patients with hypoparathyroidism; however, there is limited information on the effect of twice daily (BID) dosing of rhPTH(1-84). This was a phase I, open-label, randomized, crossover, multicenter study conducted in adult patients with chronic hypoparathyroidism. The primary objective was to assess the pharmacokinetic profile and pharmacodynamic effects of 1 day of treatment with rhPTH(1-84) administered subcutaneously at 25 μg BID, 50 μg BID, and 100 μg once daily (QD) with or without supplemental oral calcium. Safety and tolerability were evaluated as secondary objectives. In total, 33 patients with chronic hypoparathyroidism completed the study. Treatment with rhPTH(1-84), both BID and QD, over the short-term maintained serum calcium, lowered serum phosphorus, decreased urinary calcium excretion, and increased urinary phosphorus excretion. The decrease in urinary calcium excretion was numerically greater for BID than QD. Generally, baseline-adjusted pharmacokinetic parameters including area under the curve and maximum observed concentration increased with increasing rhPTH(1-84) dose, although this effect was not dose proportional. No new safety findings were observed. Our study revealed no differences thought to be clinically meaningful in pharmacokinetic or pharmacodynamic parameters with BID versus QD rhPTH(1-84) dosing. Future long-term studies are warranted to further elucidate the effects of alternative dosing strategies. © 2023 Takeda Development Center Americas, Inc and The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.

Endocrine side effects of immune checkpoint inhibitors

Immune checkpoint inhibitors (ICIs) have increasingly been the mainstay of treatment for numerous malignancies. However, due to their association with autoimmunity, ICIs have resulted in a variety of side effects that involve multiple organs including the endocrine system. In this review article, we describe our current understanding of the autoimmune endocrinopathies as a result of the use of ICIs. We will review the epidemiology, pathophysiology, clinical presentation, diagnosis, and management of the most commonly encountered endocrinopathies, including thyroiditis, hypophysitis, Type 1 diabetes, adrenalitis, and central diabetes insipidus.

The Clinical and Skeletal Effects of Long-Term Therapy of Hypoparathyroidism With rhPTH(1-84)

Hypoparathyroidism (HypoPT) is a disorder characterized by hypocalcemia, low or absent parathyroid hormone (PTH) levels, reduced bone remodeling, and high areal bone mineral density (aBMD). PTH is a therapeutic option, yet data on the prolonged clinical and skeletal effects of PTH treatment are limited. We tracked annual daily doses of calcium and active vitamin D supplements, calciotropic biochemistries, estimated glomerular filtration rate (eGFR), and aBMD measurements in 27 HypoPT patients (16 postsurgical, 11 nonsurgical) who were treated with recombinant human PTH(1-84) [rhPTH(1-84)] for at least 8 (n = 27) and up to 12 (n = 14) years. We also performed high-resolution-peripheral quantitative computed tomography (HRpQCT) imaging and report results at baseline, 5, 8, and 12 years of rhPTH(1-84) treatment. With prolonged use of rhPTH, reductions in the need for supplemental calcium and active vitamin D were maintained. The eGFR did not decline. Serum calcium was maintained within the lower limit of the normal range. aBMD by dual-energy X-ray absorptiometry (DXA) showed an increase at the lumbar spine and a decrease at the distal 1/3 radius. By HRpQCT, cortical volumetric BMD (vBMD) at the tibia decreased at year 5: -20.0% ± 1.5%. The magnitude of this reduction was mitigated in year 8: -8.5% ± 1.6% and in year 12: -10.3% ± 2.2% but all were significantly below the mean baseline value (p < 0.001). A similar pattern of decline was observed at the radius. Cortical porosity progressively increased at the tibia in year 5: 17.4% ± 10% (p < 0.05), year 8: 55.2% ± 11% (p < 0.001), and year 12: 83.5% ± 14% (p < 0.001). A similar pattern of increase was observed at the radius. Failure load, which was higher than normal at baseline, decreased but remained above normal at year 12. This is the longest experience, to date, with PTH therapy in HypoPT. These results demonstrate sustained biochemical stability but overall decreases in bone mass. © 2023 American Society for Bone and Mineral Research (ASBMR).

Association of Serum Calcium and Phosphate With Incident Cardiovascular Disease in Patients With Hypoparathyroidism

The pathophysiological basis for the increased incidence of cardiovascular disease in patients with chronic hypoparathyroidism is poorly understood. To evaluate associations between levels of albumin-corrected serum calcium, serum phosphate, and calcium-phosphate product with the odds of developing cardiovascular events in patients with chronic hypoparathyroidism with ≥1 calcitriol prescription, we conducted a retrospective nested case-control study of patients who developed a cardiovascular event and matched controls without an event. The primary outcome was the instance of cardiovascular events. An electronic medical record database was used to identify 528 patients for the albumin-corrected serum calcium analysis and 200 patients for the serum phosphate and calcium-phosphate product analyses. Patients with ≥67% of albumin-corrected serum calcium measurements outside the study-defined 2.00 to 2.25 mmol/L (8.0 to 9.0 mg/100 ml) range had 1.9-fold higher odds of a cardiovascular event (adjusted odds ratio, 95% confidence interval 1.89, 1.10 to 3.25) compared with patients with <33% of calcium measurements outside the range. Likewise, patients with any serum phosphate measurements above 0.81 to 1.45 mmol/L (2.5 to 4.5 mg/100 ml) had 3.3-fold higher odds (3.26; 1.24 to 8.58), and those with any calcium-phosphate product measurements above 4.40 mmol²/L² (55 mg²/dL²) had 4.8-fold higher odds of a cardiovascular event (95% confidence interval 1.36 to 16.81) compared with patients with no measurements above these ranges. In adult patients with chronic hypoparathyroidism, a cardiovascular event was more likely in those with a higher proportion of albumin-corrected serum calcium measurements outside 2.00 to 2.25 mmol/L (8.0 to 9.0 mg/100 ml) or any serum phosphate and any calcium-phosphate product measurements above the normal population range.

Long-Term Safety and Efficacy of Recombinant Human Parathyroid Hormone (1-84) in Adults With Chronic Hypoparathyroidism

Context

Chronic hypoparathyroidism is conventionally treated with oral calcium and active vitamin D to reach and maintain targeted serum calcium and phosphorus levels, but some patients remain inadequately controlled.

Objective

To assess long-term safety and efficacy of recombinant human parathyroid hormone (1-84) (rhPTH(1-84)) treatment.

Methods

This was an open-label extension study at 12 US centers. Adults (n = 49) with chronic hypoparathyroidism were included. The intervention was rhPTH(1-84) for 6 years. The main outcome measures were safety, biochemical measures, oral supplement doses, bone indices.

Results

Thirty-eight patients (77.6%) completed the study. Throughout 72 months, mean albumin-adjusted serum calcium was within 2.00 to 2.25 mmol/L (8.0-9.0 mg/dL). At baseline, 65% of patients with measurements (n = 24/37) were hypercalciuric; of these, 54% (n = 13/24) were normocalciuric at month 72. Mean serum phosphorus declined from 1.6 ± 0.19 mmol/L at baseline (n = 49) to 1.3 ± 0.20 mmol/L at month 72 (n = 36). Mean estimated glomerular filtration rate was stable. rhPTH(1-84)-related adverse events were reported in 51.0% of patients (n = 25/49); all but 1 event were mild/moderate in severity. Mean oral calcium supplementation reduced by 45% ± 113.6% and calcitriol by 74% ± 39.3%. Bone turnover markers declined by month 32 to a plateau above pretreatment values; only aminoterminal propeptide of type 1 collagen remained outside the reference range. Mean bone mineral density z score fell at one-third radius and was stable at other sites.

Conclusion

6 years of rhPTH(1-84) treatment was associated with sustained improvements in biochemical parameters, a reduction in the percentage of patients with hypercalciuria, stable renal function, and decreased supplement requirements. rhPTH(1-84) was well tolerated; no new safety signals were identified.

Evaluation of management of patients with postoperative permanent hypoparathyroidism. How close are we to the targets?

BACKGROUND

Postoperative hypoparathyroidism (PO-HypoPT) is a complication usually seen after thyroid surgery. PO-HypoPT, which lasts longer than 6 months is defined permanently. The aim of this study was to evaluate how close permanent PO-HypoPT patients can approach target values.

METHODS

One hundred seven patients who were followed-up with permanent diagnosis of PO-HypoPT between 2016-2020 were included in the study. The study protocol includes serum albumin corrected total calcium (Alb-sCa), phosphate (P), Ca-P product, and 24 h urine calcium measurements. Laboratory measurements of the patients include the values recorded in 4-year visits and in the last visit. In addition, radiological reports of renal/abdominal ultrasound and cranial tomography examinations performed in our hospital for any reason during this period were also reviewed.

RESULTS

When looking at the total measurements in the 4-year period, the Alb-sCa level was below the target in most of the measurements (68.1%). P level was higher than normal in 296 (46.2%) measurements. Twenty-four h urine ca excretion was measured 185 times in total visits, and 81 (43.7%) of these measurements showed hypercalciuric values. The patient's latest visit measurements were evaluated on 4 targets (Alb-sCa, P, Ca-P product and 24 h urine Ca excretion). The number of patients meeting all four targets was only 21 (19.6%). Six (7.5%) patients had kidney stones or nephrocalcinosis. Three (0.09%) patients with imaging had calcification in the basal ganglia.

CONCLUSIONS

Our study shows that the management of the patients with PO-HypoPT is suboptimal with active vitamin D and cholecalciferol treatment.

Seudohipoparatiroidismo: enfermedad huérfana en endocrinología. Reporte de un caso

Resumen Introducción. El seudohipoparatiroidismo (SPT) es un trastorno genético poco frecuente que se caracteriza por la resistencia a la hormona paratiroidea (PTH). En Colombia existen pocos reportes sobre esta enfermedad, por lo que la publicación del presente caso contribuye a aumentar el interés en su búsqueda en el ámbito clínico. Presentación del caso. Hombre de 18 años con antecedente de hipotiroidismo (diagnosticado a los 4 meses de nacido), retraso del crecimiento, desarrollo puberal tardío, obesidad, braquidactilia, fracturas patológicas, osteocondroma femoral, insomnio, parestesias y estreñimiento crónico, quien asistió al servicio de endocrinología de un hospital de tercer nivel de Bogotá (Colombia) remitido luego de haber estado hospitalizado por un episodio convulsivo. En dicha hospitalización los laboratorios evidenciaron hipocalcemia, hiperfosfatemia y 25-OH vitamina D en rango de insuficiencia con niveles elevados de PTH, y los estudios imagenológicos demostraron osificaciones heterotópicas y calcificaciones de ganglios basales del cerebro. Al paciente se le realizó un estudio genético que confirmó el diagnóstico de SPT1A, por lo que se le inició manejo con suplencia de calcio, colecalciferol y quelantes de fósforo, con lo cual evolucionó satisfactoriamente. Tanto el paciente como sus familiares de primer grado recibieron asesoramiento y valoración interdisciplinaria. Conclusiones. El SPT1A es un trastorno genético complejo poco conocido pero de alta importancia clínica dentro de los diagnósticos diferenciales de hipocalcemia que debe considerarse ya que sin el diagnóstico y tratamiento oportunos, los pacientes pueden presentar consecuencias metabólicas graves y potencialmente fatales.

Management of Hypoparathyroidism

Hypoparathyroidism (HypoPT) is a rare disorder characterized by hypocalcemia in the presence of a low or inappropriately normal parathyroid hormone level. HypoPT is most commonly seen after neck surgery, which accounts for approximately 75% of cases, whereas approximately 25% have HypoPT due to nonsurgical causes. In both groups of patients, conventional therapy includes calcium and active vitamin D analogue therapy aiming to maintain serum calcium concentration in the low normal or just below the normal reference range and normalize serum phosphorus, magnesium concentrations, and urine calcium levels. The limitations of conventional therapy include wide fluctuations in serum calcium, high pill burden, poor quality of life, and renal complications. Parathyroid hormone (PTH) replacement therapy may improve the biochemical profile in those in whom conventional therapy proves unsatisfactory. Based on a systematic review and meta-analysis of the literature, the panel made a graded recommendation suggesting conventional therapy as first line therapy rather than administration of PTH (weak recommendation, low quality evidence). When conventional therapy is deemed unsatisfactory, the panel considers use of PTH. Because pregnancy and lactation are associated with changes in calcium homeostasis, close monitoring is required during these periods with appropriate adjustment of calcium and active vitamin D analogue therapy to ensure that serum calcium remains in the mid to low normal reference range in order to avoid maternal and fetal complications. Emerging therapies include molecules with prolonged PTH action as well as different mechanisms of action that may significantly enhance drug efficacy and safety. © 2022 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).

Initial Assessment and Monitoring of Patients with Chronic Hypoparathyroidism: A Systematic Current Practice Survey

Chronic hypoparathyroidism (HypoPT) is associated with significant morbidity and impaired quality of life (QoL). The goals of management for chronic HypoPT include improvement in QoL and the prevention of both hypo- and hypercalcemia symptoms and long-term complications. Several groups have provided consensus statements and guidelines on the management of HypoPT; however, due to limited evidence, these recommendations have largely been based on literature reviews, expert opinion, and consensus statements. The objective of this study was to use a systematic approach to describe current practice for the initial assessment and follow-up of patients with chronic HypoPT. We developed a survey asking experts in the field to select the responses that best reflect their current practice. The survey found no differences in responses between nonsurgical and postsurgical patient assessment. For new patients, respondents usually performed an assessment of serum lab profile (calcium [either albumin-adjusted or ionized], magnesium, creatinine, phosphate, 25-hydroxyvitamin D), 24-hour urine (creatinine, calcium), and a renal ultrasound to evaluate for the presence of nephrocalcinosis or nephrolithiasis. For follow-up patients, most respondents perform blood tests and urine tests every 6 months or less frequently. The reported clinical practice patterns for monitoring for complications of chronic HypoPT vary considerably among respondents. Based on the responses in this systematic expert practice survey, we provide practice suggestions for initial assessment and follow-up of patients with chronic HypoPT. In addition, we highlight areas with significant variation in practice and identify important areas for future research. © 2022 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).

Parathyroid Hormone Therapy for Managing Chronic Hypoparathyroidism: A Systematic Review and Meta-Analysis

The efficacy and safety of parathyroid hormone (PTH) therapy for managing long-term hypoparathyroidism is being evaluated in ongoing clinical trials. We undertook a systematic review and meta-analysis of currently available randomized controlled trials to investigate the benefits and harms of PTH therapy and conventional therapy in the management of patients with chronic hypoparathyroidism. To identify eligible studies, published in English, we searched Embase, PubMed, and Cochrane CENTRAL from inception to May 2022. Two reviewers independently extracted data and assessed the risk of bias. We defined patients' important outcomes and used grading of recommendations, assessment, development, and evaluation (GRADE) to provide the structure for quantifying absolute effects and rating the quality of evidence. Seven randomized trials of 12 publications that enrolled a total of 386 patients proved eligible. The follow-up duration ranged from 1 to 36 months. Compared with conventional therapy, PTH therapy probably achieves a small improvement in physical health-related quality of life (mean difference [MD] 3.4, 95% confidence interval [CI] 1.5-5.3, minimally important difference 3.0, moderate certainty). PTH therapy results in more patients reaching 50% or greater reduction in the dose of active vitamin D and calcium (relative risk [RR] = 6.5, 95% CI 2.5-16.4, 385 more per 1000 patients, high certainty). PTH therapy may increase hypercalcemia (RR =2.4, 95% CI 1.2-5.04, low certainty). The findings may support the use of PTH therapy in patients with chronic hypoparathyroidism. Because of limitations of short duration and small sample size, evidence from randomized trials is limited regarding important benefits of PTH therapy compared with conventional therapy. Establishing such benefits will require further studies. © 2022 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).

Complications, Symptoms, Presurgical Predictors in Patients With Chronic Hypoparathyroidism: A Systematic Review

The complications and symptoms of hypoparathyroidism remain incompletely defined. Measuring serum parathyroid hormone (PTH) and calcium levels early after total thyroidectomy may predict the development of chronic hypoparathyroidism. The study aimed (i) to identify symptoms and complications associated with chronic hypoparathyroidism and determine the prevalence of those symptoms and complications (Part I), and (ii) to examine the utility of early postoperative measurements of PTH and calcium in predicting chronic hypoparathyroidism (Part II). We searched Medline, Medline In-Process, EMBASE, and Cochrane CENTRAL to identify complications and symptoms associated with chronic hypoparathyroidism. We used two predefined criteria (at least three studies reported the complication and symptom and had statistically significantly greater pooled relative estimates). To estimate prevalence, we used the median and interquartile range (IQR) of the studies reporting complications and symptoms. For testing the predictive values of early postoperative measurements of PTH and calcium, we used a bivariate model to perform diagnostic test meta-analysis. In Part I, the 93 eligible studies enrolled a total of 18,973 patients and reported on 170 complications and symptoms. We identified nine most common complications or symptoms probably associated with chronic hypoparathyroidism. The complications or symptoms and the prevalence are as follows: nephrocalcinosis/nephrolithiasis (median prevalence among all studies 15%), renal insufficiency (12%), cataract (17%), seizures (11%), arrhythmia (7%), ischemic heart disease (7%), depression (9%), infection (11%), and all-cause mortality (6%). In Part II, 18 studies with 4325 patients proved eligible. For PTH measurement, regarding the posttest probability, PTH values above 10 pg/mL 12-24 hours postsurgery virtually exclude chronic hypoparathyroidism irrespective of pretest probability (100%). When PTH values are below 10 pg/mL, posttest probabilities range from 3% to 64%. Nine complications and symptoms are probably associated with chronic hypoparathyroidism. A PTH value above a threshold of 10 pg/mL 12-24 hours after total thyroidectomy is a strong predictor that the patients will not develop chronic hypoparathyroidism. Patients with PTH values below the threshold need careful monitoring as some will develop chronic hypoparathyroidism. © 2022 American Society for Bone and Mineral Research (ASBMR).

Epidemiology and Financial Burden of Adult Chronic Hypoparathyroidism

Chronic hypoparathyroidism is characterized by low serum calcium, increased serum phosphorus, and inappropriately low or decreased serum parathyroid hormone. This rare disorder is associated with a variety of complications. The prevalence, incidence, mortality, financial burden, and epidemiology of complications of this disorder are not well understood. This narrative review summarizes current information on the epidemiology and complications of chronic hypoparathyroidism. The reported prevalence of chronic hypoparathyroidism ranges from 6.4-37/100,000, and the incidence is reported to be 0.8-2.3/100,000/year. Mortality is not increased in studies from Denmark or South Korea but was increased in studies from Scotland and Sweden. The financial burden of this disorder is substantial because of increased health care resource utilization in two studies but not well quantitated. Recognized complications include hypercalciuria, nephrocalcinosis, kidney stones, and chronic kidney disease; low bone turnover and possibly upper extremity fractures; cardiac and vascular calcifications; basal ganglia calcifications, cataracts, infections, neuropsychiatric complications, and difficulties with pregnancy. This review concludes that chronic hypoparathyroidism is a rare disorder associated with significant morbidity that may not increase overall mortality but is associated with a substantial financial burden. © 2022 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).

Evaluation and Management of Hypoparathyroidism Summary Statement and Guidelines from the Second International Workshop

This clinical practice guideline addresses the prevention, diagnosis, and management of hypoparathyroidism (HypoPT) and provides evidence-based recommendations. The HypoPT task forces included four teams with a total of 50 international experts including representatives from the sponsoring societies. A methodologist (GG) and his team supported the taskforces and conducted the systematic reviews. A formal process following the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) methodology and the systematic reviews provided the structure for seven of the guideline recommendations. The task force used a less structured approach based on narrative reviews for 20 non-GRADEd recommendations. Clinicians may consider postsurgical HypoPT permanent if it persists for >12 months after surgery. To predict which patients will not develop permanent postsurgical HypoPT, we recommend evaluating serum PTH within 12 to 24 hours post total thyroidectomy (strong recommendation, moderate quality evidence). PTH > 10 pg/mL (1.05 pmol/L) virtually excludes long-term HypoPT. In individuals with nonsurgical HypoPT, genetic testing may be helpful in the presence of a positive family history of nonsurgical HypoPT, in the presence of syndromic features, or in individuals younger than 40 years. HypoPT can be associated with complications, including nephrocalcinosis, nephrolithiasis, renal insufficiency, cataracts, seizures, cardiac arrhythmias, ischemic heart disease, depression, and an increased risk of infection. Minimizing complications of HypoPT requires careful evaluation and close monitoring of laboratory indices. In patients with chronic HypoPT, the panel suggests conventional therapy with calcium and active vitamin D metabolites as first-line therapy (weak recommendation, low-quality evidence). When conventional therapy is deemed unsatisfactory, the panel considers the use of PTH. © 2022 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).

Treatment options in hypoparathyroidism

Hypoparathyroidism remains the single endocrine deficiency disease that is not habitually treated with the missing hormone. In this article, we aim to provide a review of the conventional approach and the novel therapies as well as an overview of the perspectives on the treatment of this rare condition. We conducted a literature review on the conventional therapy using vitamin D analogs and calcium salts, indications for thiazide diuretics and phosphorus binders, PTH analogs history and usage, and the drugs that are currently being tested in clinical trials. Conventional treatment involves calcium salts and vitamin D analogs. Thiazide diuretics can be used to reduce hypercalciuria in some cases. A low-phosphate diet is recommended, and phosphate binders are rarely needed. During pregnancy, a careful approach is necessary. The use of PTH analogs is a new approach despite the limitation of high cost. Studies have included modified PTH molecules, calcilytics, microencapsulation of human parathyroid cells, and allotransplantation.

Hypoparathyroidism: update of guidelines from the 2022 International Task Force

The 2022 International Task Force guidelines for chronic hypoparathyroidism will be published within several months in the Journal of Bone and Mineral Research. These guidelines update the original guidelines published in 2016, and include new information from literature published since then. Chronic postsurgical hypoparathyroidism is now defined as lasting for at least 12 months after surgery, rather than 6 months. Chronic postsurgical hypoparathyroidism may be predicted by serum PTH <10 pg/mL in the first 12-24 hours after surgery. The most common symptoms and complications of chronic hypoparathyroidism based on the literature are summarized in detail. How to monitor and manage patients with hypoparathyroidism is described in detail where recommendations can be given. These guidelines are intended to frame the diagnosis and care of patients with chronic hypoparathyroidism for at least the next five years.

UK national chronic hypoparathyroidism audit

OBJECTIVES

Individuals with chronic hypoparathyroidism may experience suboptimal medical care with high frequency of unplanned hospitalisation and iatrogenic harm. In 2015 the European Society for Endocrinology published consensus guidelines on the management of chronic hypoparathyroidism. We set out to audit compliance with these guidelines.

METHODS

Using these recommendations as audit standards we worked with the Society for Endocrinology and Parathyroid UK to conduct a national audit of management of chronic hypoparathyroidism in the United Kingdom. Endocrine leads in 117 endocrine departments were invited to participate in the survey by completing a data collection tool on up to 5 sequential cases of chronic hypoparathyroidism seen in their outpatient clinics in the preceding 12 months. Data were collected on 4 treatment standards and 9 monitoring standards. Data on hospitalisations and Quality of Life monitoring were also collected.

RESULTS

Responses were received from 22 departments giving a response rate of 19%, concerning 80 individual cases. The mean age of subjects was 48.4 years. The main findings were that the commonest cause of hypoparathyroidism was post surgical (66.3%). Treatments taken by the group included activated vitamin D analogues (96.3%), oral calcium salts (66.3%), vitamin D supplements (17.5%), thiazide diuretics (5%) and rhPTH_1-34 (1.3%). Compliance with the audit standards varied between 98.8% and 60% for the treatment standards and between 91.3% and 20% for the monitoring standards. Some of the areas of weakness revealed include low rates of 24 h urinary calcium excretion monitoring, serum magnesium monitoring and low rates of renal imaging where indicated. In addition and importantly, 16.3% of subjects had experienced at least one hospital admission in the preceding 12 months.

CONCLUSION

We conclude that further improvements in the UK national standard of management of chronic hypoparathyroidism should be made and that this will benefit both quality of life, morbidity and potentially mortality in this group of patients.

Multicenter retro-prospective observational study on chronic hypoparathyroidism and rhPTH (1-84) treatment

PURPOSE

The main purpose of this study was to investigate the effects of 12 months of rhPTH (1-84) (Natpar^®) treatment in a cohort of patients selected according to the indications of hypoparathyroidism guidelines. The use of recombinant human PTH (1-84) [rhPTH (1-84)] is approved as hormonal replacement therapy in patients with hypoparathyroidism not adequately controlled with conventional therapy.

METHODS

It is a multicenter, observational, retro-prospective, open label study. Eleven Italian Endocrinological centers, members of Hypoparathyroidism Working Group of the Italian Society of Endocrinology (HypoparaNET) were involved. Main outcome measures were serum and urinary calcium and phosphate concentration, calcium-phosphate product, renal function, oral calcium and vitamin D doses, and clinical manifestations.

RESULTS

Fourteen adult subjects, affected by chronic hypoparathyroidism, were treated with rhPTH (1-84) for 12 months. At 12 months of rhPTH (1-84) treatment, 61.5% of patients discontinued calcium supplement and 69.2% calcitriol. Mean albumin-adjusted total serum calcium levels quickly normalized after initiation of rhPTH (1-84) treatment compared to baseline (p = 0.009), remaining in the normal range until 12 months. Rare hypo-hypercalcemia episodes were reported. Renal function was maintained normal and no renal complications were reported. Serum and urinary phosphate and urinary calcium were maintained in the normal range. Mean phosphatemia levels linearly decreased from 3 months up to 12 months compared to baseline (p = 0.014). No severe adverse events were described.

CONCLUSIONS

Biochemical and clinical results confirm the efficacy and safety of rhPTH (1-84) therapy, which represents an important option for hypoparathyroid patients unresponsive to conventional therapy.

Lower Risk of Cardiovascular Events in Adult Patients with Chronic Hypoparathyroidism Treated with rhPTH(1-84): A Retrospective Cohort Study

Introduction

Patients with chronic hypoparathyroidism are at increased risk of cardiovascular disease. This study evaluated the risk of developing cardiovascular conditions over a period of 5 years in adult patients with chronic hypoparathyroidism treated with recombinant human parathyroid hormone (1–84), rhPTH(1–84), compared with a historical control cohort of patients not treated with rhPTH(1–84).

Methods

This retrospective cohort study comprised patients with chronic hypoparathyroidism treated with rhPTH(1–84) in the REPLACE (NCT00732615), RELAY (NCT01268098), and RACE (NCT01297309) clinical trials, and controls selected from the IBM^® Explorys electronic medical record database (January 2007–August 2019) who did not receive parathyroid hormone but who had enrollment criteria similar to those for the clinical trials. Cardiovascular outcomes were the first diagnosis of cerebrovascular, coronary artery, peripheral vascular disease, or heart failure during the study period.

Results

We evaluated 113 adult patients with chronic hypoparathyroidism treated with rhPTH(1–84) and 618 control patients who did not receive rhPTH(1–84). Over the 5-year follow-up period, 3.5% of patients (n = 4) in the rhPTH(1–84) cohort had a cardiovascular event compared with 16.3% (n = 101) in the control cohort. Kaplan–Meier analysis demonstrated that patients in the rhPTH(1–84) cohort had lower risk of experiencing a cardiovascular event compared with patients in the control cohort (P = 0.005). Multivariable analyses adjusted for baseline variables showed that patients in the rhPTH(1–84) cohort had 75% lower risk for a cardiovascular event compared with patients in the control cohort (adjusted hazard ratio, 0.25 [95% CI 0.08–0.81]; P = 0.020).

Conclusion

Long-term treatment with rhPTH(1–84) was associated with a lower risk of incident cardiovascular conditions compared with conventional therapy in patients with chronic hypoparathyroidism. Previous studies demonstrated that mineral homeostasis was maintained with lower use of calcium and active vitamin D when rhPTH(1–84) was added to conventional therapy. Future studies are needed to understand whether improved regulation of mineral homeostasis conferred by rhPTH(1–84) may provide long-term cardiovascular benefits to patients with chronic hypoparathyroidism.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12325-022-02198-y.

Parathyroid hormone of ≥1.6 pmol/L at 6 months is associated with recovery in 'long-term' post-surgical hypoparathyroidism

Objective

Post-surgical hypoparathyroidism (PoSH) usually settles within few months after thyroid surgery, but several patients require long-term supplementation with calcium/activated vitamin D. When PoSH persists beyond 6 months, it is considered 'chronic' or 'permanent', however, late recovery has been reported. The aim of this study was to determine the frequency of late recovery and explore factors predicting late recovery of parathyroid function.

Methods

Adult patients undergoing total/completion thyroidectomy between 2009 and 2018 were included in this retrospective cohort observational study. The records of patients with evidence of PoSH were reviewed to identify those with persisting PoSH at 6 months. Demographic, biochemical, surgical, pathological, and clinical follow-up data were collected and analysed.

Results

Out of 911 patients undergoing thyroidectomy, 270 were identified with PoSH. Of these, 192 were started on supplements and 138 (71.9%) recovered within 6 months. Of the remaining 54 patients, 35 had ongoing PoSH with median (range) follow-up of 3.4 (0.5-11.1) years. Nineteen patients were weaned off supplements and achieved remission at median (range) follow-up of 1.3 (0.6-4.8) years. All of those who recovered had a PTH of ≥1.6 pmol/L at 6 months. There was no difference in age, gender, diagnosis, type, and extent of surgery between those who did and did not show late recovery.

Conclusions

Recovery from PoSH is common beyond 6 months, raising the question whether a 6-month threshold to define 'long-term' PoSH is appropriate. The chances of recovery are high (~50%) in patients with PTH level ≥1.6 pmol/L at 6 months, where attempts at weaning may be focussed.

Good Clinical Practice of the Italian Society of Thalassemia and Haemoglobinopathies (SITE) for the Management of Endocrine Complications in Patients with Haemoglobinopathies

Background: The treatment of endocrinopathies in haemoglobinopathies is a continually expanding research area; therefore, recommendations supporting the appropriateness of treatments are a pressing need for the medical community. Methods: The Management Committee of SITE selected and gathered a multidisciplinary and multi-professional team, including experts in haemoglobinopathies and experts in endocrinopathies, who have been flanked by experts with methodological and organizational expertise, in order to formulate recommendations based on the available scientific evidence integrated by personal clinical experience. The project followed the systematic approach for the production of clinical practice guidelines according to the methodology suggested by the National Center for Clinical Excellence, Quality and Safety of Care (CNEC). Results: Out of 14 topics, 100 clinical questions were addressed, and 206 recommendations were elaborated on. The strength of recommendations, panel agreement, a short general description of the topic, and the interpretation of evidence were reported. Conclusions: Good Practice Recommendations are the final outcome of translational research and allow one to transfer to the daily clinical practice of endocrine complications in haemoglobinopathies.

European Expert Consensus on Practical Management of Specific Aspects of Parathyroid Disorders in Adults and in Pregnancy: Recommendations of the ESE Educational Program of Parathyroid Disorders

This European expert consensus statement provides recommendations for the diagnosis and management of primary hyperparathyroidism (PHPT), chronic hypoparathyroidism in adults (HypoPT), and parathyroid disorders in relation to pregnancy and lactation. Specified areas of interest and unmet needs identified by experts at the second ESE Educational Program of Parathyroid Disorders (PARAT) in 2019, were discussed during two virtual workshops in 2021, and subsequently developed by working groups with interest in the specified areas. PHPT is a common endocrine disease. However, its differential diagnosing to familial hypocalciuric hypercalcemia (FHH), the definition and clinical course of normocalcemic PHPT, and the optimal management of its recurrence after surgery represent areas of uncertainty requiring clarifications. HypoPT is an orphan disease characterized by low calcium concentrations due to insufficient PTH secretion, most often secondary to neck surgery. Prevention and prediction of surgical injury to the parathyroid glands are essential to limit the disease-related burden. Long-term treatment modalities including the place for PTH replacement therapy and the optimal biochemical monitoring and imaging surveillance for complications to treatment in chronic HypoPT, need to be refined. The physiological changes in calcium metabolism occurring during pregnancy and lactation modify the clinical presentation and management of parathyroid disorders in these periods of life. Modern interdisciplinary approaches to PHPT and HypoPT in pregnant and lactating women and their newborns children are proposed. The recommendations on clinical management presented here will serve as background for further educational material aimed for a broader clinical audience, and were developed with focus on endocrinologists in training.

Identifying Clinical Characteristics of Hypoparathyroidism in Turkey: HIPOPARATURK-NET Study

Hypoparathyroidism is an orphan disease with ill-defined epidemiology that is subject to geographic variability. We conducted this study to assess the demographics, etiologic distribution, treatment patterns and complication frequency of patients with chronic hypoparathyroidism in Turkey. This is a retrospective, cross-sectional database study, with collaboration of 30 endocrinology centers located in 20 cities across seven geographical regions of Turkey. A total of 830 adults (mean age 49.6 ± 13.5 years; female 81.2%) with hypoparathyroidism (mean duration 9.7 ± 9.0 years) were included in the final analysis. Hypoparathyroidism was predominantly surgery-induced (n = 686, 82.6%). The insulting surgeries was carried out mostly due to benign causes in postsurgical group (SG) (n = 504, 73.5%) while patients in nonsurgical group (NSG) was most frequently classified as idiopathic (n = 103, 71.5%). The treatment was highly dependent on calcium salts (n = 771, 92.9%), calcitriol (n = 786, 94.7%) and to a lower extent cholecalciferol use (n = 635, 76.5%) while the rate of parathyroid hormone (n = 2, 0.2%) use was low. Serum calcium levels were most frequently kept in the normal range (sCa 8.5-10.5 mg/dL, n = 383, 46.1%) which might be higher than desired for this patient group. NSG had a lower mean plasma PTH concentration (6.42 ± 5.53 vs. 9.09 ± 7.08 ng/l, p < 0.0001), higher daily intake of elementary calcium (2038 ± 1214 vs. 1846 ± 1355 mg/day, p = 0.0193) and calcitriol (0.78 ± 0.39 vs. 0.69 ± 0.38 mcg/day, p = 0.0057), a higher rate of chronic renal disease (9.7% vs. 3.6%, p = 0.0017), epilepsy (6.3% vs. 1.6%, p = 0.0009), intracranial calcifications (11.8% vs. 7.3%, p < 0.0001) and cataracts (22.2% vs. 13.7%, p = 0.0096) compared to SG. In conclusion, postsurgical hypoparathyroidism is the dominant etiology of hypoparathyroidism in Turkey while the nonsurgical patients have a higher disease burden with greater need for medications and increased risk of complications than the postsurgical patients.

Practice patterns for chronic hypoparathyroidism: data from patients and physicians in France

CONTEXT

Recent guidelines have provided recommendations for the care of patients with chronic hypoparathyroidism. Very little is known about actual physicians' practices or their adherence to such guidelines.

OBJECTIVE

To describe the physicians' practice patterns and their compliance with international guidelines.

DESIGN

The cohort studies included were Épi-Hypo (118 physicians and 107 patients, from September 2016 to December 2019) and ePatients (110 patients, November 2019).

METHODS

Internet-based cohorts involving all settings at a nationwide level (France). Participants were (i) physicians treating patients with chronic hypoparathyroidism and patients with chronic hypoparathyroidism either participating in the (ii) Épi-Hypo study (Épi-Hypo 2019 patients), or (iii) Hypoparathyroidism France, the national representative association (ePatients).

RESULTS

The physicians' specialties were mainly endocrinology (61%), nephrology (28%), family medicine (2.5%), pediatrics (2.5%), rheumatology (2%), or miscellaneous (4%) and 45% were practicing in public universities. The median number of pharmaceutical drug classes prescribed was three per patient. The combination of active vitamin D and calcium salt was given to 59 and 58% of ePatients and Épi-Hypo 2019 patients, respectively. Eighty-five percent of ePatients and 87% of physicians reported monitoring plasma calcium concentrations at a steady state at least twice a year. In 32 and 26% of cases, respectively, ePatients and physicians reported being fully in accordance with international guidelines that recommend targeting symptoms, plasma calcium and phosphate values, and urine calcium excretion.

CONCLUSIONS

The care of patients with chronic hypoparathyroidism involves physicians with very different practices, so guidelines should include and target other specialists as well as endocrinologists. Full adherence to the guidelines is low in France.

Assessment of calcium and vitamin D medications adherence in patients with hypoparathyroidism after thyroidectomy

In this study, we found that patients with hypoparathyroidism had a problem with calcium medication compliance, and this problem increased with the duration of the disease. We also showed that patients are concerned about the possible side effects of drugs.

INTRODUCTION

In this study, we aimed to evaluate adherence to active vitamin D and calcium replacement in patients with post-surgical hypoparathyroidism.

METHODS

To elucidate the medication adherence, we performed a questionnaire survey using the six-item "Medication adherence questionnaire"(MAQ). The first, second, and sixth questions reflect the motivation status of the patients whereas the third, fourth, and fifth questions reflect the knowledge about the medication that is received. The responses are scored and patients are classified regarding their motivation to and knowledge about the particular drug.

RESULTS

Totally, 64 patients (male: 12/female: 52; mean age 48.6±11.6 years) who had post-operative hypoparathyroidism were included in our study. Median disease durance was 60 months (min-max: 12-295 months). We found that motivation score of calcium usage was significantly lower compared to vitamin D usage (p<0.001). The calcium motivation score was reversely correlated with disease duration (r= -0.256 and p=0.046). The most common worry about calcium usage was nephrotoxicity, and the most common worries about calcitriol treatment were kidney damage and polyuria. One-third of the patients were taking oral calcium and calcitriol less than the recommended dose.

CONCLUSION

One-third of patients lack motivation to use calcium whereas half of the patients experiences anxiety about drug-related side effects. This is a preliminary study showing that vital calcium and active vitamin D intake may be interrupted due to side effect anxiety.

Association of Calcium and Phosphate Levels with Incident Chronic Kidney Disease in Patients with Hypoparathyroidism: A Retrospective Case-Control Study

OBJECTIVE

Reasons for the increased incidence of chronic kidney disease (CKD) in patients with chronic hypoparathyroidism are poorly understood. This study evaluated associations between levels of albumin-corrected serum calcium, serum phosphate, and calcium-phosphate product and the odds of CKD development in patients with chronic hypoparathyroidism.

DESIGN

A retrospective nested case-control study of adult patients with chronic hypoparathyroidism who had ≥1 prescription for calcitriol who developed CKD and matched controls who did not develop CKD were selected from the IBM® Explorys electronic medical record database. Patients. The study included a cohort of 300 patients for the albumin-corrected serum calcium analysis and 80 patients for the serum phosphate and calcium-phosphate product analyses. Measurements. We examined associations between albumin-corrected serum calcium, serum phosphate and calcium-phosphate product levels, and the risk of devloping CKD (defined as ≥2 outpatient estimated glomerular filtration values <60 mL/min/1.73 m² occuring ≥3 months apart or ≥1 diagnostic code for CKD stages 3-5).

RESULTS

Individuals who had ≥67% of albumin-corrected serum calcium measurements outside, above, or below the study-defined range (2.00-2.25 mmol/L [8.0-9.0 mg/dL]) had 3.5-, 2.9-, and 2.7-fold higher odds of developing CKD (adjusted odds ratios [95% CI]: 3.46 [1.82-6.56], 2.85 [1.30-6.28], and 2.68 [1.16-6.15]), respectively, compared with patients who had <33% of albumin-corrected calcium measurements in those ranges. There was no association between developing CKD and having any serum phosphate measurements or any calcium-phosphate product measurements above normal population ranges.

CONCLUSION

In adult patients with chronic hypoparathyroidism, a higher proportion of albumin-corrected calcium measurements outside of the 2.00-2.25 mmol/L (8.0-9.0 mg/dL) range was associated with higher odds of developing CKD.

Five-Year Estimated Glomerular Filtration Rate in Adults with Chronic Hypoparathyroidism Treated with rhPTH(1-84): A Retrospective Cohort Study

INTRODUCTION

Chronic hypoparathyroidism is associated with higher risk of developing chronic kidney disease compared with the general population. This study evaluated changes in estimated glomerular filtration rate (eGFR) over a 5-year period in adult patients with chronic hypoparathyroidism treated with recombinant parathyroid hormone (1-84), rhPTH(1-84), compared with a historical control cohort of patients who did not receive rhPTH(1-84).

METHODS

This retrospective cohort study included patients with chronic hypoparathyroidism treated with rhPTH(1-84) in the REPLACE (NCT00732615), RELAY (NCT01268098), RACE (NCT01297309), and HEXT (NCT01199614 and continuation study NCT02910466) clinical trials. A historical control cohort who did not receive parathyroid hormone but who had enrollment criteria similar to those for the clinical trials was selected from the IBM® Explorys electronic medical record database (January 2007-August 2019). Outcomes of interest were the annual rate of change in eGFR from baseline (i.e., eGFR slope) and the predicted eGFR change from baseline at years 1 through 5.

RESULTS

The study comprised 72 adult patients with chronic hypoparathyroidism treated with rhPTH(1-84) and 176 control patients who did not receive rhPTH(1-84). Over 5 years, eGFR remained stable in the rhPTH(1-84) cohort, whereas eGFR declined at a rate of 1.67 mL/min/1.73 m² per year in the control cohort (P < 0.001 for eGFR slope in the control cohort). At 5 years, predicted eGFR in the rhPTH(1-84) cohort increased from baseline by 1.21 mL/min/1.73 m², whereas eGFR in the control cohort declined by 10.36 mL/min/1.73 m², after adjusting for baseline variables. The difference in eGFR slopes between the cohorts over 5 years was 1.37 mL/min/1.73 m² per year (95% CI 0.62-2.13; P < 0.001).

CONCLUSION

Long-term treatment with rhPTH(1-84) was associated with stable eGFR compared with eGFR decline in the controls not treated with rhPTH(1-84). Preservation of renal function conferred by rhPTH(1-84) may benefit patients with chronic hypoparathyroidism by reducing risk of long-term renal complications.

The PARADIGHM (physicians advancing disease knowledge in hypoparathyroidism) registry for patients with chronic hypoparathyroidism: study protocol and interim baseline patient characteristics

BACKGROUND

The PARADIGHM registry of adult and pediatric patients with chronic hypoparathyroidism evaluates the long-term safety and effectiveness of treatment with recombinant human parathyroid hormone, rhPTH(1-84), and describes the clinical disease course under conditions of routine clinical practice. In this first report, we detail the registry protocol and describe the baseline characteristics of two adult patient cohorts from an interim database analysis. One cohort after study entry were prescribed rhPTH(1-84), and the other cohort received conventional therapy of calcium and active vitamin D.

METHODS

An observational study of patients with chronic hypoparathyroidism in North America and Europe, collecting data for ≥10 years per patient. Main outcome measures were baseline patient demographics, clinical characteristics, medications, and disease outcome variables of symptoms, biochemical parameters, and health assessments. Baseline is the enrollment assessment for all variables except biochemical measurements in patients treated with rhPTH(1-84); those measurements were the most recent value before the first rhPTH(1-84) dose. Exclusion criteria applied to the analysis of specified outcomes included pediatric patients, patients who initiated rhPTH(1-84) prior to enrollment, and those who received rhPTH(1-34). Clinically implausible biochemical outlier data were excluded.

RESULTS

As of 30 June 2019, data of 737 patients were analyzed from 64 centers; 587 (80%) were women, mean ± SD age 49.1±16.45 years. At enrollment, symptoms reported for patients later prescribed rhPTH(1-84) (n=60) and those who received conventional therapy (n=571), respectively, included fatigue (51.7%, 40.1%), paresthesia (51.7%, 29.6%), muscle twitching (48.3%, 21.9%), and muscle cramping (41.7%, 33.8%). Mean serum total calcium, serum phosphate, creatinine, and estimated glomerular filtration rate were similar between cohorts. Health-related quality of life (HRQoL) 36-item Short Form Health Survey questionnaire scores for those later prescribed rhPTH(1-84) were generally lower than those for patients in the conventional therapy cohort.

CONCLUSIONS

At enrollment, based on symptoms and HRQoL, a greater percentage of patients subsequently prescribed rhPTH(1-84) appeared to have an increased burden of disease than those who received conventional therapy despite having normal biochemistry measurements. PARADIGHM will provide valuable real-world insights on the clinical course of hypoparathyroidism in patients treated with rhPTH(1-84) or conventional therapy in routine clinical practice.

TRIAL REGISTRATION

EUPAS16927, NCT01922440.

Hypoparathyroidism and pseudohypoparathyroidism in pregnancy: an Italian retrospective observational study

Background

Hypoparathyroidism (HypoPT) or pseudo-hypoparathyroidism (pseudo-HypoPT) during pregnancy may cause maternal and fetal/neonatal complications. In this regard, only a few case reports or case series of pregnant or lactating women have been published. The purpose of this study was to describe clinical and biochemical course, pharmacological management, and potential adverse events during pregnancy and post-partum in pregnant women with HypoPT or pseudo-HypoPT. This was a retrospective, observational, multicenter, study involving nine Italian referral centers for endocrine diseases affiliated with the Italian Society of Endocrinology and involved in “Hypoparathyroidism Working Group”.

Results

This study identified a cohort of 28 women (followed between 2005 and 2018) with HypoPT (n = 25, 84% postsurgical, 16% idiopathic/autoimmune) and pseudo-HypoPT (n = 3). In HypoPT women, the mean calcium carbonate dose tended to increase gradually from the first to third trimester (+ 12.6%) in pregnancy. This average increase in the third trimester was significantly greater compared to the pre-pregnancy period (p value = 0.03). However, analyzing the individual cases, in 44% the mean calcium dosage remained unchanged throughout gestation. Mean calcitriol doses tended to increase during pregnancy, with a statistically significant increase between the third trimester and the pre-pregnancy period (p value = 0.02). Nevertheless, analyzing the individual cases, in the third trimester most women with HypoPT (64%) maintained the same dosage of calcitriol compared to the first trimester. Both mean calcium carbonate and calcitriol doses tended to decrease from the third trimester to the post-partum six months. Most identified women (~ 70%) did not display maternal complications and (~ 90%) maintained mean serum albumin-corrected total calcium levels within the low-to-mid normal reference range (8.5 ± 0.8 mg/dl) during pregnancy. The main complications related to pregnancy period included: preterm birth (n = 3 HypoPT women), and history of miscarriages (n = 6 HypoPT women and n = 2 pseudo-HypoPT women).

Conclusion

This study shows that mean serum albumin-corrected total calcium levels were carefully monitored during pregnancy and post-pregnancy, with limited evaluation of other biochemical parameters, such as serum phosphate, 24 h urinary calcium, 25-OH vitamin D, and creatinine clearance. To avoid complications in mothers affected by (HypoPT) or (pseudo-HypoPT) and offspring, intense biochemical, clinical and pharmacological monitoring during pregnancy and breastfeeding is highly recommended.

Rapidly Developing Cataract in Young Adult Patients: Always a Matter for Further Evaluation

A cataract in the young age group is uncommon and it is usually secondary to eye trauma, intraocular inflammation, uncontrolled diabetes mellitus, and hypoparathyroidism. We report a case of a rapidly developing cataract over two years in a 21-year-old female with extensive intracranial calcification due to primary hypoparathyroidism.

Chronic hypocalcemia due to underlying hypoparathyroidism results in cataract. Extensive bilateral intracranial calcification involving basal ganglia and white matter has been rarely reported in the literature. It occurs due to the chronic deposition of calcium-phosphorus complexes.

We would like to highlight that cataract in young patients is always a matter for further evaluation. Clinicians and ophthalmologists should be aware of hypoparathyroidism as a cause of bilateral cataracts. Early diagnosis of primary hypoparathyroidism can save patients from many complications.

[Registries of parathyroid glands diseases in the Russian Federation]

The most important and effective way to organize nationwide the healthcare, as well as monitoring and routing for patients with endocrine diseases, is the creation of an unified medical record (Endocard). The Endocard is also aimed at maximizing the opportunity for professionals and researchers on various scientific issues. Registries are the potential informational and analytical platform to achieve this goal. They include the basic information on the epidemiological and clinical features of the most severe diseases such as diabetes mellitus. Given the lack of large-scale epidemiological data on the parathyroid glands pathology - primary hyperparathyroidism and hypoparathyroidism - the registers of these diseases that collects a common dataset and clinician and patient reported outcomes are of particular interest.

[Review of clinical practice guidelines for hypoparathyroidism]

Hypoparathyroidism is a rare disorder characterized by the absent or inappropriately decreased serum parathyroid hormone in the parathyroid glands, which is accompanied by impaired calcium-phosphorus metabolism.The main etiology of hypoparathyroidism remains damage or removal of the parathyroid glands during neck surgery. In view of the incidence of thyroid cancer, primary hyperparathyroidism and other pathologies of the neck organs, which radical treatment can lead to the parathyroid gland impairment, an increased number of patients with hypoparathyroidism is expected. Autoimmune hypoparathyroidism is the second most common form of the disease, usually occurring as part of type 1 autoimmune polyglandular syndrome. Autoimmune hypoparathyroidism usually occurs in childhood and is characterized by a severe course of the disease, especially in the case of concomitant malabsorption syndrome.Chronic hypoparathyroidism of any etiology requires lifelong multicomponent therapy, as well as careful monitoring and an individual approach to choose the optimal treatment strategy. In the absence of adequate follow-up, the risks of long-term complications significantly increase, particularly in the renal, cardiovascular systems; in the soft tissues and in the brain, it could lead to visual disturbances; pathology of the musculoskeletal system with a decreased bone remodeling and a potential risk of fractures, as well as to the neurocognitive disorders and an impaired health-related quality of life.Timely diagnosis, rational medical therapy and management strategy may reduce the risks of short-term and long-term complications, frequency of hospitalizations and disability of patients, as well as improve the prognosis.This review covers the main issues of Russian guidelines for the management of chronic hypoparathyroidism, approved in 2021, including laboratory and instrumental evaluation, treatment approaches and follow-up. This guidelines also include the recommendations for special groups of patients: with acute hypocalcemia, hypoparathyroidism during pregnancy.

[The Russian registry of chronic hypoparathyroidism and clinical decision support system integration]

According to available research, chronic hypoparathyroidism is a relatively rare disease characterized by low serum calcium levels and the absence or deficiency of parathyroid hormone. The chronic course of the disease is associated with the multicomponent medical therapy, careful dynamic monitoring to reduce the risks of various complications in different organs and systems as well as disability and mortality.The Russian registry of patients with chronic postsurgical and nonsurgical hypoparathyroidism has started its work in 2020, based on data of the Endocrinology Research Centre. The main goals of the Registry are the assessment of the actual prevalence, incidence of hypoparathyroidism, the key epidemiological characteristics, the analysis of the clinical features and medical therapy of chronic hypoparathyroidism in Russian Federation.This article covers all objectives of this project, the methodology for maintaining the registry of chronic postsurgical and nonsurgical hypoparathyroidism, the analytical possibilities of its use, including the integration of a decision support system designed to help specialists in real clinical practice follow the algorithms for diagnosis and treatment of the disease, approved by clinical guidelines.The registry of chronic postsurgical and nonsurgical hypoparathyroidism is located on a single platform for the registers of endocrinopathies, regulated by the Endocrinology Research Centre (http://gipopt.clin-reg.ru/).

Therapy with PTH 1-34 or calcitriol and calcium in diverse etiologies of hypoparathyroidism over 27 years at a single tertiary care center

OBJECTIVE

Hypoparathyroidism has heterogeneous genetic and acquired etiologies with a broad spectrum of severity. Herein we describe the clinical outcomes of the largest cohort of hypoparathyroid patients reported to date, who were followed over 27-years.

DESIGN

Pooled analysis of current and past studies describing the differential responses to PTH 1-34 injections vs conventional therapy among the varied hypoPT etiologies.

METHODS

192 participants (ages 2-74 years) with hypoparathyroidism who received either calcitriol and calcium or PTH 1-34 by subcutaneous injection.

RESULTS

Among the 4 main etiologic categories of hypoparathyroidism (autoimmune polyglandular failure type 1, activating mutation of the calcium receptor, surgical, and idiopathic hypoparathyroidism), we reveal significant differences in PTH 1-34 dose requirements, prevalence of nephrocalcinosis, biomarkers of mineral homeostasis, and pharmacodynamic profiles. Serum 1,25-dihydroxyvitamin D₃ increased significantly (P < 0.001) and 25-hydroxyvitamin D levels decreased during PTH 1-34 injections compared to calcitriol therapy (P < 0.01). Post-surgical patients achieved consistently lower urine calcium excretion over long-term PTH 1-34 therapy compared to conventional therapy (p < 0.001), but this was not achieved in the other etiologies. At study entry, patients had a high prevalence of renal insufficiency and nephrocalcinosis which were directly related to the duration of hypoparathyroidism (P < 0.03). Renal function remained stable during participation in our studies for both PTH 1-34 and conventional therapies.

CONCLUSIONS

We conclude that the effects and dose-response of PTH 1-34 treatment differ according to the etiology of hypoparathyroidism. Postsurgical hypoPT maintained mean serum calcium levels in the mid- to low-normal range while concurrently maintaining normal mean urine calcium during long-term twice-daily PTH 1-34 therapy.

Safety and Efficacy of Radiofrequency Ablation of Thyroid Nodules-Expanding Treatment Options in the United States

CONTEXT

Radiofrequency ablation (RFA) has only recently gained popularity in the United States for treatment of thyroid nodules (TNs), with a limited number of patients having undergone the procedure in this country.

OBJECTIVE

To evaluate the safety and efficacy of RFA of TNs performed in an outpatient setting in the United States.

METHODS

This is a retrospective, single-center study of 53 patients who underwent RFA of 58 TNs between November 2018 and January 2021. The reduction in volume of nodule, cosmetic and symptomatic improvement, effect on thyroid function, and complications following RFA were assessed.

RESULTS

Eleven out of 53 patients were excluded from the analysis. A total of 47 benign TNs (23 nonfunctioning thyroid nodules [NFTNs] and 24 autonomously functioning thyroid nodules [AFTNs]), were assessed after RFA. The median reduction in volume was 70.8% after a median follow-up period of 109 days, with symptomatic and cosmetic improvement (P < 0.0001). Compared with larger nodules, smaller nodules had greater volume reduction (P = 0.0266). RFA improved thyrotropin (TSH) in AFTNs (P value = 0.0015) and did not affect TSH in NFTNs (P value = 0.23). There were no major complications; however, 1 patient had self-limited local bleeding and another had transient voice change that recovered in 6 months.

CONCLUSION

RFA is a safe and efficacious treatment for symptomatic NFTNs and AFTNs in our population and is especially effective for smaller nodules. RFA should be considered an alternative for TNs in patients who cannot or do not want to undergo surgery.

Burden of illness in patients with chronic hypoparathyroidism not adequately controlled with conventional therapy: a Belgium and the Netherlands survey

PURPOSE

To determine the burden of illness in patients with not adequately controlled chronic hypoparathyroidism receiving conventional therapy in Belgium and the Netherlands.

METHODS

Data were generated from a cross-sectional, two-part online survey where endocrinologists from both countries and nephrologists from Belgium were invited by phone to participate. Part 1 included collecting data on general management of patients with hypoparathyroidism. In Part 2, physicians were requested to provide data on one or two current cases of patients with chronic hypoparathyroidism not adequately controlled on conventional therapy. Data collected included aetiology of hypoparathyroidism, clinical manifestations, comorbidities, results of laboratory and other investigations used for diagnosis and screening for complications, therapy received, and physician's perception of impaired quality of life (QoL).

RESULTS

Thirty-six endocrinologists and 29 nephrologists from Belgium and 28 endocrinologists from the Netherlands participated in the survey. Data included clinical symptoms, biochemical parameters, and QoL for 97 current patients with not adequately controlled chronic hypoparathyroidism on conventional therapy. Median duration of not adequately controlled hypoparathyroidism was 2.2 years, range 0.17-20.0. Most patients had neuromuscular (85%) and/or neurological (67%) symptoms, 71% had abnormal biochemical parameters, 10% were overweight, and physicians perceived that 71% had impaired QoL. Most frequently reported comorbidities included hypertension (25%), renal comorbidity (20%), diabetes mellitus (12%), and dyslipidaemia (11%).

CONCLUSION

Patients with chronic hypoparathyroidism not adequately controlled on conventional therapy experience a substantial burden of illness, mainly due to persistence of symptoms and presence of multiple comorbidities.

Changes in treatment needs for chronic postoperative hypoparathyroidism during initiation of conventional treatment compared to stable phase of treatment

INTRODUCTION

In our clinical experience, need for doses of active vitamin D and calcium supplements changes during the period following a diagnosis of postsurgical hypoparathyroidism (HypoPT), but only sparse data are available. In the present study, we aimed to investigate the magnitude of changes in need for activated vitamin D (alfacalcidol) and calcium supplements during initiation of therapy as well as time to be expected until a stable phase was achieved. Furthermore, we determined the frequency of (unexpected) episodes of hypo- and hypercalcaemia after reaching a steady state for alfacalcidol and calcium.

METHODS

Retrospective study of twenty-four patients with chronic postsurgical HypoPT (>6 months) diagnosed from 2016 to 2018. Data were extracted from medical records on doses of alfacalcidol and calcium as well as ionized plasma calcium levels (P-Ca2+) from time of diagnosis and until 86 weeks after surgery.

RESULTS

Patients were treated with alfacalcidol and calcium in order to maintain a stable concentration of P-Ca2+. Our data demonstrated a great variation in treatment needs until 11 weeks after surgery, where the mean doses of alfacalcidol stabilize, while calcium doses stabilized a bit earlier. After the stable phase had emerged, 21 out of 24 patients continued to have one or more episodes of spontaneous hypo- or hypercalcaemia.

CONCLUSIONS

Patients with chronic HypoPT attain a steady state for alfacalcidol 11 weeks after the diagnosis. Continuous monitoring of P-Ca2+ is of continued importance after reaching steady state due to a high frequency of spontaneous hypo- or hypercalcaemia.

Basal Ganglia Calcification Is Associated With Local and Systemic Metabolic Mechanisms in Adult Hypoparathyroidism

CONTEXT

Hypoparathyroidism is characterized by low serum calcium, increased serum phosphorus, and inappropriately low or decreased serum parathyroid hormone, which may be associated with soft tissue calcification in the basal ganglia of the brain.

OBJECTIVE

To assess the prevalence and factors involved in the pathophysiology of basal ganglia calcification (BGC) in the brain in chronic hypoparathyroidism and to evaluate proposed pathophysiologic mechanisms.

DESIGN

Case-control study with retrospective review of medical records over 20 years.

SETTING

Single academic medical center.

PATIENTS

142 patients with chronic hypoparathyroidism and computed tomography (CT) head scans followed between January 1, 2000 and July 9, 2020, and 426 age- and sex-matched controls with CT head scans over the same interval.

INTERVENTIONS

None.

MAIN OUTCOME MEASURES

Demographic, biochemical, and CT head imaging findings, with semiquantitative assessment of volumetric BGC.

RESULTS

The study found that 25.4% of 142 patients followed for a median of 17 years after diagnosis of chronic hypoparathyroidism had BGC, which developed at a younger age than in controls. BGC was 5.1-fold more common in nonsurgical patients and less common in postsurgical patients. Low serum calcium and low calcium/phosphate ratio correlated with BGC. Neither serum phosphorus nor calcium × phosphate product predicted BGC. Lower serum calcium was associated with greater volume of BGC. The extent of BGC varied widely, with nonsurgical patients generally having a greater volume and distribution of calcification.

CONCLUSIONS

BGC is associated with low serum calcium and low serum calcium/phosphate ratio, which may be related to severity of the disease, its etiology, or duration of treatment.

Canadian national hypoparathyroidism registry: an overview of hypoparathyroidism in Canada

PURPOSE

To evaluate the epidemiology, presentation and management of hypoparathyroidism in Canada. Hypoparathyroidism is associated with significant morbidity and poor quality of life. We present baseline results from the Canadian National Hypoparathyroidism Registry, a prospective observational study evaluating hypoparathyroidism in Canada.

METHODS

Our study enrolled 130 patients with hypoparathyroidism. Patients were followed every 6 months with clinical and lab assessments. We present baseline data in this manuscript.

RESULTS

Seventy percent (91/130) of patients had postsurgical hypoparathyroidism, 30% (39/130) of patients had nonsurgical hypoparathyroidism due to autoimmune, genetic or idiopathic causes, and a molecular diagnosis was confirmed in 11 of these 39 patients. Pseudohypoparathyroidism was confirmed in 4/39 patients, DiGeorge syndrome in 2/39 patients, Barakat syndrome with a mutation in the GATA3 gene in 1/39, and activating mutations of the CASR gene in 3/39 patients with nonsurgical hypoparathyroidism. Renal complications with nephrocalcinosis or nephrolithiasis were present in 27% (14/52) of patients with postsurgical disease and 17% (4/24) of patients with nonsurgical hypoparathyroidism. Basal ganglia calcification was noted on imaging in 15% (n = 5/34) of patients with postsurgical hypoparathyroidism and 37% (n = 7/19) of patients with nonsurgical hypoparathyroidism.

CONCLUSIONS

Hypercalciuria was more commonly seen in those with renal complications of nephrocalcinosis, nephrolithiasis or CKD, and hyperphosphatemia was more commonly seen in those with basal ganglia calcification. Hospitalization occurred in 28% of those with postsurgical hypoparathyroidism and 46% of those with nonsurgical hypoparathyroidism. Hypoparathyroidism is associated with significant morbidity. Effective strategies to reduce the short-and long-term complications of hypoparathyroidism need to be developed and evaluated.