Is severe hypocalcemia immediately life-threatening?

Identification of novel risk factors for postoperative severe hypocalcemia in patients with primary hyperparathyroidism undergoing parathyroidectomy: a case control study

BACKGROUND

Patients with primary hyperparathyroidism (PHPT) are at risk for severe hypocalcemia (SH) following parathyroidectomy (PTX), but limited data exist on the predictors of SH. We aimed to identify risk factors for early postoperative SH after PTX in patients with PHPT and to evaluate the predictive value of clinical parameters.

METHODS

A retrospective review of patients with PHPT who underwent PTX between January 2010 and December 2022 was performed. A total of 46 patients were included in the study, with 15 (32.6%) experiencing postoperative SH, 19 (41.3%) having calculi in the ureter or kidney, and 37 (80.4%) having osteoporosis. Patients were divided into SH and non-SH groups based on postoperative serum calcium levels. Preoperative biochemical indicators, bone turnover markers, and renal function parameters were analyzed and correlated with postoperative SH.

RESULTS

Statistically significant (P < 0.05) differences were found in preoperative serum calcium (serum Ca), intact parathyroid hormone, serum phosphorus (serum P), serum Ca/P, percentage decrease of serum Ca, total procollagen type 1 intact N-terminal propeptide, osteocalcin (OC), and alkaline phosphatase levels between the two groups. Multivariate analysis showed that serum P (odds ratio [OR] = 0.989; 95% confidence interval [95% CI] = 0.981-0.996; P = 0.003), serum Ca (OR = 0.007; 95% CI = 0.001-0.415; P = 0.017), serum Ca/P (OR = 0.135; 95% CI = 0.019-0.947; P = 0.044) and OC levels (OR = 1.012; 95% CI = 1.001-1.024; P = 0.036) were predictors of early postoperative SH. The receiver operating characteristic curve analysis revealed that serum P (area under the curve [AUC] = 0.859, P < 0.001), serum Ca/P (AUC = 0.735, P = 0.010) and OC (AUC = 0.729, P = 0.013) had high sensitivity and specificity.

CONCLUSION

Preoperative serum P, serum Ca/P and osteocalcin levels may identify patients with PHPT at risk for early postoperative SH after PTX.

Quantitative Assessment of Intracellular Effectors and Cellular Response in RAGE Activation

The review delves into the methods for the quantitative assessment of intracellular effectors and cellular response of Receptor for Advanced Glycation End products (RAGE), a vital transmembrane receptor involved in a range of physiological and pathological processes. RAGE bind to Advanced Glycation End products (AGEs) and other ligands, which in turn activate diverse downstream signaling pathways that impact cellular responses such as inflammation, oxidative stress, and immune reactions. The review article discusses the intracellular signaling pathways activated by RAGE followed by differential activation of RAGE signaling across various diseases. This will ultimately guide researchers in developing targeted and effective interventions for diseases associated with RAGE activation. Further, we have discussed how PCR, western blotting, and microscopic examination of various molecules involved in downstream signaling can be leveraged to monitor, diagnose, and explore diseases involving proteins with unique post-translational modifications. This review article underscores the pressing need for advancements in molecular approaches for disease detection and management involving RAGE.

Severe Hypocalcemia With Denosumab Among Older Female Dialysis-Dependent Patients

Importance

Dialysis-dependent patients experience high rates of morbidity from fractures, yet little evidence is available on optimal treatment strategies. Chronic kidney disease-mineral and bone disorder is nearly universal in dialysis-dependent patients, complicating diagnosis and treatment of skeletal fragility.

Objective

To examine the incidence and comparative risk of severe hypocalcemia with denosumab compared with oral bisphosphonates among dialysis-dependent patients treated for osteoporosis.

Design, Setting, and Participants

Retrospective cohort study of female dialysis-dependent Medicare patients aged 65 years or older who initiated treatment with denosumab or oral bisphosphonates from 2013 to 2020. Clinical performance measures including monthly serum calcium were obtained through linkage to the Consolidated Renal Operations in a Web-Enabled Network database.

Exposures

Denosumab, 60 mg, or oral bisphosphonates.

Main Outcomes and Measures

Severe hypocalcemia was defined as total albumin-corrected serum calcium below 7.5 mg/dL (1.88 mmol/L) or a primary hospital or emergency department hypocalcemia diagnosis (emergent care). Very severe hypocalcemia (serum calcium below 6.5 mg/dL [1.63 mmol/L] or emergent care) was also assessed. Inverse probability of treatment-weighted cumulative incidence, weighted risk differences, and weighted risk ratios were calculated during the first 12 treatment weeks.

Results

In the unweighted cohorts, 607 of 1523 denosumab-treated patients and 23 of 1281 oral bisphosphonate-treated patients developed severe hypocalcemia. The 12-week weighted cumulative incidence of severe hypocalcemia was 41.1% with denosumab vs 2.0% with oral bisphosphonates (weighted risk difference, 39.1% [95% CI, 36.3%-41.9%]; weighted risk ratio, 20.7 [95% CI, 13.2-41.2]). The 12-week weighted cumulative incidence of very severe hypocalcemia was also increased with denosumab (10.9%) vs oral bisphosphonates (0.4%) (weighted risk difference, 10.5% [95% CI, 8.8%-12.0%]; weighted risk ratio, 26.4 [95% CI, 9.7-449.5]).

Conclusions and Relevance

Denosumab was associated with a markedly higher incidence of severe and very severe hypocalcemia in female dialysis-dependent patients aged 65 years or older compared with oral bisphosphonates. Given the complexity of diagnosing the underlying bone pathophysiology in dialysis-dependent patients, the high risk posed by denosumab in this population, and the complex strategies required to monitor and treat severe hypocalcemia, denosumab should be administered after careful patient selection and with plans for frequent monitoring.

Management of Postthyroidectomy Hypoparathyroidism and Its Effect on Hypocalcemia-Related Complications: A Meta-Analysis

OBJECTIVE

The aim of this Meta-analysis is to evaluate the impact of different treatment strategies for early postoperative hypoparathyroidism on hypocalcemia-related complications and long-term hypoparathyroidism.

DATA SOURCES

Embase.com, MEDLINE, Web of Science Core Collection, Cochrane Central Register of Controlled Trials, and the top 100 references of Google Scholar were searched to September 20, 2022.

REVIEW METHODS

Articles reporting on adult patients who underwent total thyroidectomy which specified a treatment strategy for postthyroidectomy hypoparathyroidism were included. Random effect models were applied to obtain pooled proportions and 95% confidence intervals. Primary outcome was the occurrence of major hypocalcemia-related complications. Secondary outcome was long-term hypoparathyroidism.

RESULTS

Sixty-six studies comprising 67 treatment protocols and 51,096 patients were included in this Meta-analysis. In 8 protocols (3806 patients), routine calcium and/or active vitamin D medication was given to all patients directly after thyroidectomy. In 49 protocols (44,012 patients), calcium and/or active vitamin D medication was only given to patients with biochemically proven postthyroidectomy hypoparathyroidism. In 10 protocols (3278 patients), calcium and/or active vitamin D supplementation was only initiated in case of clinical symptoms of hypocalcemia. No patient had a major complication due to postoperative hypocalcemia. The pooled proportion of long-term hypoparathyroidism was 2.4% (95% confidence interval, 1.9-3.0). There was no significant difference in the incidence of long-term hypoparathyroidism between the 3 supplementation groups.

CONCLUSIONS

All treatment strategies for postoperative hypocalcemia prevent major complications of hypocalcemia. The early postoperative treatment protocol for postthyroidectomy hypoparathyroidism does not seem to influence recovery of parathyroid function in the long term.

Preoperative Vitamin D and Calcium Administration in Patients Undergoing Thyroidectomy: A Systematic Review and Meta-analysis of Randomized Controlled Trials

Objective

This systematic review and meta-analysis aimed to assess whether preoperative administration of calcium and vitamin D prevents postoperative hypocalcemia.

Data Sources

A computerized search in Medline, Embase, and CENTRAL databases was performed.

Review Methods

Trials comparing preoperative calcium and vitamin D administration with either placebo or nothing were eligible for inclusion. The primary outcomes were the occurrence of laboratory hypocalcemia, mean postoperative calcium level, and symptomatic hypocalcemia. The secondary outcomes were the development of permanent hypoparathyroidism and length of hospitalization. Continuous outcomes were represented as standardized mean difference (SMD), and dichotomous outcomes were represented as risk ratio (RR).

Results

Nine trials that enrolled 1079 patients were found eligible. Postoperative laboratory hypocalcemia occurred less in patients who received preoperative calcium and vitamin D, but it was not statistically significant (RR = 0.77, 95% CI: 0.60-1.00; P = .05). Mean postoperative calcium level was significantly higher in the intervention group (SMD = 0.10, 95% CI: 0.07-0.12; P < .00001). The number of patients with symptomatic hypocalcemia was significantly lower in the intervention group (RR = 0.54, 95% CI: 0.38-0.76; P = .0005). There was no significant difference between the 2 groups in cases of permanent hypoparathyroidism and length of hospitalization.

Conclusion

Administration of calcium and vitamin D preoperatively achieves lower rates of postthyroidectomy symptomatic hypocalcemia in comparison with no intervention.

A symptom-based algorithm for calcium management after thyroid surgery: a prospective multicenter study

Objective

Evidence-based treatment guidelines for the management of postthyroidectomy hypocalcemia are absent. The aim of this study was to evaluate a newly developed symptom-based treatment algorithm including a protocolized attempt to phase out supplementation.

Methods

In a prospective multicenter study, patients were treated according to the new algorithm and compared to a historical cohort of patients treated with a biochemically based approach. The primary outcome was the proportion of patients receiving calcium and/or alfacalcidol supplementation. Secondary outcomes were calcium-related complications and predictors for supplementation.

Results

One hundred thirty-four patients were included prospectively, and compared to 392 historical patients. The new algorithm significantly reduced the proportion of patients treated with calcium and/or alfacalcidol during the first postoperative year (odds ratio (OR): 0.36 (95% CI: 0.23-0.54), P < 0.001), and persistently at 12 months follow-up (OR: 0.51 (95% CI: 0.28-0.90), P < 0.05). No severe calcium-related complications occurred, even though calcium-related visits to the emergency department and readmissions increased (OR: 11.5 (95% CI: 4.51-29.3), P <0.001) and (OR: 3.46 (95% CI: 1.58-7.57), P < 0.05), respectively. The proportional change in pre- to postoperative parathyroid hormone (PTH) was an independent predictor for supplementation (OR: 1.04 (95% CI: 1.02-1.07), P < 0.05).

Conclusions

Symptom-based management of postthyroidectomy hypocalcemia and a protocolized attempt to phase out supplementation safely reduced the proportion of patients receiving supplementation, although the number of calcium-related hospital visits increased. For the future, we envision a more individualized treatment approach for patients at risk for delayed symptomatic hypocalcemia, including the proportional change in pre- to post- operative PTH.

Severe hypocalcemia after denosumab treatment leading to refractory ventricular tachycardia and veno-arterial extracorporeal membrane oxygenation support: a case report

BACKGROUND

Severe hypocalcemia may lead to life-threatening arrhythmias. Denosumab is an effective treatment for osteoporosis that allows long intervals between doses. However, there is a risk of hypocalcemia in some patients. Due to the long half-life of denosumab, emergency physicians caring for patients presenting with symptoms of hypocalcemia may not be aware of the medication, and adverse effects may last longer.

CASE PRESENTATION

A 55-year-old woman with a history of systemic lupus erythematosus (SLE) and anxiety disorder called for an ambulance for symptoms of hyperventilation and muscle cramps. After evaluation at the local hospital, she developed pulseless ventricular tachycardia and was resuscitated by defibrillation by the hospital staff. After conversion to sinus rhythm, she was transported to a tertiary center. Upon arrival, pulseless ventricular tachycardia occurred again, and veno-arterial extracorporeal membrane oxygenation (ECMO) and intra-aortic balloon pumping (IABP) were implemented. Laboratory results showed severe hypocalcemia (corrected calcium level of 5.3 mg/dL) whereupon intravenous calcium supplementation was started. She had received the first dose of denosumab (60 mg) by subcutaneous injection 24 days prior to hospitalization. She was eventually weaned from ECMO and IABP support.

CONCLUSION

Cardiac arrest due to hypocalcemia is relatively rare but can be fatal. In the present case, hyperventilation may have acutely exacerbated pre-existing hypocalcemia, leading to ventricular tachycardia. The patient had a slightly decreased serum calcium level prior to denosumab. Close monitoring may be preferable after the primary dose of denosumab in selected patients. Emergency physicians caring for patients who may be suffering from symptoms/signs of hypocalcemia must be mindful of medications that have long half-lives and affect electrolyte balance when treating fatal arrhythmia due to hypocalcemia.

Risk Factor Analysis and Prediction of Severe Hypocalcemia after Total Parathyroidectomy without Auto-Transplantation in Patients with Secondary Hyperparathyroidism

OBJECTIVE

Our study aimed to develop and validate a nomogram to predict severe hypocalcemia (SH) before total parathyroidectomy (TPTX) without auto-transplantation in patients with secondary hyperparathyroidism.

METHODS

A total of 299 consecutive patients who underwent TPTX without transplantation for secondary hyperparathyroidism were selected from the General Hospital of Northern Theater Command between January 2013 and December 2021. Of these, patients who underwent surgery between January 2013 and December 2020 formed the training cohort (n = 208) to develop a nomogram, and those who underwent surgery thereafter formed the validation cohort (n = 91) to validate the performance of this nomogram. Univariate and multivariate logistic regression analyses were used to identify the risk factors associated with SH, and then, a nomogram was constructed.

RESULTS

The incidence of postoperative SH was 27.9% and 35.2% in the training and validation cohorts, respectively. The preoperative factors associated with SH were younger age, lower serum calcium (Ca) level, higher intact parathyroid hormone (iPTH) level, and higher serum alkaline phosphatase (ALP) level. Incorporating these 4 factors, the nomogram achieved good concordance indexes of 0.866 (95%CI, 0.816-0.916) and 0.867 (95% CI, 0.793-0.941) in predicting SH in the training and validation cohorts, respectively, and had well-fitted calibration curves. The positive predictive values of the nomogram were 64.7% (54.1%-78.4%) and 75.0% (58.6%-88.5%), and negative predictive values of the nomogram were 90.0% (82.9%-93.6%) and 86.4% (73.5%-94.0%) for the training and validation cohorts, respectively.

CONCLUSIONS

We developed and validated a nomogram for the prediction of SH in patients who underwent TPTX without auto-transplantation for secondary hyperparathyroidism. Our nomogram may facilitate the identification of high-risk SH in patients after TPTX and optimization of preoperative decision-making.

The Positive and Negative Effects of Calcium Supplementation on Mortality in Septic ICU Patients Depend on Disease Severity: A Retrospective Study from the MIMIC-III

Background. Calcium administration in septic patients with hypocalcemia is a controversial issue. The present study preliminarily investigated the effects of calcium supplementation on the length of hospitalization and mortality in septic ICU patients with different severities of hypocalcemia and disease. Method. A total of 5761 eligible septic patients, including 2689 who received calcium supplementation and 3072 who did not receive calcium supplementation, were extracted from the Medical Information Mart for Intensive Care III (MIMIC-III) database. The cofounding covariates between the calcium supplement and nonsupplement groups were balanced using the propensity score matching model. We compared the length of stay (LOS) in the ICU and hospital with 28-day and hospital mortality and stratified the analysis according to the sequential organ failure assessment (SOFA) score and ionized calcium (iCa) at the first ICU admission in the matched groups. Results. The results showed that iCa at the first ICU admission was associated with mortality in sepsis patients (HR: 0.421; 95% CI: 0.211∼0.837), but the lowest mortality rate was observed in patients with mild hypocalcemia. A total of 993 paired patients were included in the analysis after propensity score matching. Regardless of the SOFA score or presence of iCa, the LOS in the ICU was higher in the calcium supplement group than in the nonsupplement group. The survival analysis was stratified by the SOFA score and showed that calcium supplementation reduced mortality when the patient’s SOFA score was ≥8 ( $p=0.002$ ), and it worsened the outcome when the patient’s SOFA score was ≤4 ( $p=0.010$ ). It had no significant effect on patients with SOFA scores ranging from 5 to 7 ( $p=0.911$ ). Conclusion. Our results showed that mild hypocalcemia may be protective in septic patients, and calcium supplementation may have positive and negative effects on mortality depending on disease severity. The SOFA score may be a valuable clinical index for decisions regarding calcium administration.

Parathyroidectomy for dialysis patients in the era of calcimimetics: The surgeons' point of view

Calcimimetics is a new drug for lowering serum parathyroid hormone (PTH), calcium and phosphate in patients with hyperparathyroidism (HPT) on long-term dialysis. It became available on market in 2006. The impact of calcimimetics on the treatment by parathyroidectomy (PTx) was reviewed from the surgeons' point of view. Cure of renal HPT by calcimimetics is not feasible, but calcimimetics can improve preoperative cardiac ventricle ejection fractions by lowering serum PTH. Heart failure is not necessarily a contraindication for PTx. PTx should be done before irreversible organ damage occurs. Limb gangrenes is an ominous sign and should be prevented by frequent checkup for peripheral arterial circulation. The impact of renal osteodystrophy on the quality of life and as indirect cause of mortality deserves more attention in patients with renal HPT. Delayed referral to PTx leads to more complicated patients. A consensus between nephrologists and surgeons about propitious timing for PTx is necessary. Future prospect on the surgical treatment of renal HPT is proposed. Supplemental figure; http://links.lww.com/ASAIO/A782.

Type I Brugada-Like Pattern with Arrhythmia in Severe Anemia

Introduction

Brugada syndrome (BrS) has been described as an inherited cardiac disorder due to gene mutations, which contributes to sudden cardiac death, especially in Southeast Asians. Brugada phenocopy, which has the same pattern caused by etiologies such as metabolic disorder, is potentially reversible and avoids unnecessary implantable medical devices.

Case Presentation

We reported a rare case of Brugada phenocopy in a 60-years-old Indonesian male with severe anemia and a history of chronic urinary tract bleeding and hemorrhoid. Brugada phenocopy, widely known as BrS look-alike, has been linked to sodium, potassium, and calcium channel dysfunction. This condition is uncommon and has been related to metabolic conditions such as anemia. Iron deficiency anemia induces ischemia in the myocardium and degrades the calcium channels. During the transfusion, hypocalcemia precipitates temporary arrhythmia with right ventricular outflow tract origin, which reverts after the hypocalcemia has been treated.

Conclusion

Due to the possibility of altered ion channels and how rarely hypocalcemia induces arrhythmia, this makes understanding the pathogenesis of Brugada phenocopy essential. Though caution is necessary, early recognition can improve prognosis as Brugada phenocopy is potentially reversible.

Association of hypocalcemia with in-hospital mortality and complications in patients with acute pulmonary embolism: results from the 2017 Nationwide Inpatient Sample

Background

Acute pulmonary embolism (PE) is a common cause for hospitalization associated with significant mortality and morbidity. Disorders of calcium metabolism are a frequently encountered medical problem. The effect of hypocalcemia is not well defined on the outcomes of patients with PE. We aimed to identify the prognostic value of hypocalcemia in hospitalized PE patients utilizing the 2017 Nationwide Inpatient Sample (NIS).

Methods

In this retrospective study, we selected patients with a primary diagnosis of Acute PE using ICD 10 codes. They were further stratified based on the presence of hypocalcemia. We primarily aimed to compare in-hospital mortality for PE patients with and without hypocalcemia. We performed multivariate logistic regression analysis to adjust for potential confounders. We also used propensity‐matched cohort of patients to compare mortality.

Results

In the 2017 NIS, 187,989 patients had a principal diagnosis of acute PE. Among the above study group, 1565 (0.8%) had an additional diagnosis of hypocalcemia. 12.4% of PE patients with hypocalcemia died in the hospital in comparison to 2.95% without hypocalcemia. On multivariate regression analysis, PE and hypocalcemia patients had 4 times higher odds (aOR-4.03, 95% CI 2.78–5.84, p < 0.001) of in-hospital mortality compared to those with only PE. We observed a similarly high odds of mortality (aOR = 4.4) on 1:1 propensity-matched analysis. The incidence of acute kidney injury (aOR = 2.62, CI 1.95–3.52, p < 0.001), acute respiratory failure (a0R = 1.84, CI 1.42–2.38, p < 0.001), sepsis (aOR = 4.99, CI 3.08–8.11, p < 0.001) and arrhythmias (aOR = 2.63, CI 1.99–3.48, p < 0.001) were also higher for PE patients with hypocalcemia.

Conclusion

PE patients with hypocalcemia have higher in-hospital mortality than those without hypocalcemia. The in-hospital complications were also higher, along with longer length of stay.

The Effect of Calcium Ions on Mechanosensation and Neuronal Activity in Proprioceptive Neurons

Proprioception of all animals is important in being able to have coordinated locomotion. Stretch activated ion channels (SACs) transduce the mechanical force into electrical signals in the proprioceptive sensory endings. The types of SACs vary among sensory neurons in animals as defined by pharmacological, physiological and molecular identification. The chordotonal organs within insects and crustaceans offer a unique ability to investigate proprioceptive function. The effects of the extracellular environment on neuronal activity, as well as the function of associated SACs are easily accessible and viable in minimal saline for ease in experimentation. The effect of extracellular [Ca2+] on membrane properties which affect voltage-sensitivity of ion channels, threshold of action potentials and SACs can be readily addressed in the chordotonal organ in crab limbs. It is of interest to understand how low extracellular [Ca2+] enhances neural activity considering the SACs in the sensory endings could possibly be Ca2+ channels and that all neural activity is blocked with Mn2+. It is suggested that axonal excitability might be affected independent from the SAC activity due to potential presence of calcium activated potassium channels (K(Ca)) and the ability of Ca2+ to block voltage gated Na+ channels in the axons. Separating the role of Ca2+ on the function of the SACs and the excitability of the axons in the nerves associated with chordotonal organs is addressed. These experiments may aid in understanding the mechanisms of neuronal hyperexcitability during hypocalcemia within mammals.

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.

Dyselectrolytemia-management and implications in hemodialysis (Review)

Hemodialysis is a method for the renal replacement therapy followed by series of acute and chronic complications. Dyselectrolytemia appears in patients undergoing dialysis through mechanisms related to the chronic kidney disease and/or to the dialysis therapy and for this group of patients it is associated with an increase of morbidity and mortality. The dialysate has a standard composition, which can be modified according to the patient's characteristics. During hemodialysis patients are exposed to 18,000-36.000 litres of water/year, and the water purity along with the biochemical composition of the dialysate are essential. The individualization of the dialysis prescription is recommended for each patient and it has an important role in preventing the occurrence of dyselectrolyemia. The individualization of the treatment prescription according to the blood constants of each patient is the prerogative of the nephrologist and the association of the electrolyte imbalances with the patients cardiovascular mortality explains the importance of paying special attention to them.

Diagnosis and management of hypocalcemia

The aim of this clinical narrative review is to summarize and critically appraise the literature on the differential diagnosis of hypocalcemia and to provide its correct management. Calcium is essential for muscle contraction and neurotransmitter release, but clinical manifestations of hypocalcaemia (serum calcium level <8 mg/dl; 2.12 mmol/L) may involve almost any organ and system and may range from asymptomatic to life-threating conditions. Disorders causing hypocalcemia can be divided into parathyroid hormone (PTH) and non-PTH mediated. The most frequent cause of hypocalcemia is postsurgical hypoparathyroidism, while a more comprehensive search for other causes is needed for appropriate treatment in the non PTH-mediated forms. Intravenous calcium infusion is essential to raise calcium levels and resolve or minimize symptoms in the setting of acute hypocalcemia. Oral calcium and/or vitamin D supplementation is the most frequently used as treatment of chronic hypocalcemia. In hypoparathyroidism, providing the missing hormone with the use of the recombinant human (rh) PTH(1-84) has been recently approved both by the Food and Drug Administration (FDA) and the European Medicines Agency (EMA). This new therapy has the advantage of being effective for correcting serum calcium levels and significantly reducing the daily requirements of calcium and active vitamin D supplements. However, due to the high cost, a strict selection of candidates to this therapy is necessary. More challenging is the long-term hypocalcemia treatment, due to its associated complications. The development of long-acting recombinant human PTH will probably modify the management of chronic hypoparathyroidism in the future.