Treatment Of Hypoparathyroidism Research Articles

SUN-520 Brain Calcinosis Syndrome Manifesting as Cerebellar Ataxia in a Chronic Hypoparathyroid Patient

BACKGROUND Chronic hypoparathyroidism in adults is usually secondary to previous thyroid surgery and is characterized by low calcuim and inappropriately low circulating PTH levels. The clinical presentation of hypoparathyroidism can vary with the serum calcium levels and chronicity of hypocalcemia. Hypoparathyroidism can cause intracranial calcifications but extensive intracranial calcifications are rare. Brain calcinosis syndrome is defined as bilateral calcium accumulation in the brain parenchyma, most often within the basal ganglia. Such intracranial calcifications occur in 0.3-1.5% of patients with hypoparathyroidism, often detected incidentally. The mechanism of intracranial calcification is not completely understood. Its occurrence with hypocalcemia suggests that increased calcium-phosphorus complex formation plays a role. THE CASE A 63-year old female was admitted due to dizziness. She had a fall prior confinement due to loss of consciousness lasting for less than 5 minutes, however, recovered afterwards. No head injury was detected at the referring hospital. She is hypertensive with good BP control on Amlodipine 2.5 mg and Losartan 50 mg taken once daily. She had total thyroidectomy for colloid adenoma 20 years ago, prescribed with Levothyroxine 100 mcg once daily but taken with poor compliance. She had episodes of cold intolerance, hoarseness, and weight gain. On examination, she was conscious and coherent. Blood pressure was 95/60 mm Hg, heart rate of 67 beats per minute. A midline neck scar from previous surgery was visible, no palpable neck mass or lymph nodes. Notable on the neurological examination were positive Rhomberg test and dysmetria evaluated by finger-to-nose test. Chvostek’s and Trosseau’s signs were negative. Motor, sensory and cranial nerve functions were intact. Plain cranial CT scan showed extensive cranial calcifications on both basal ganglia, corona radiata, brainstem and cerebellum. Blood tests revealed low levels of ionized calcium (0.91 mmol/L; N 1.12-1.32 mmol/L)), intact PTH (0.51 pg/ml; N 15-65 pg/ml), and FT4 (5.54 pmol/L; N 12-22 pmol/L). TSH was elevated (32.85 uIU/ml; N 0.27- 4.2 uIU/ml). Calcium with active vitamin D and levothyroxine were given. Physical rehabilitation initiated. Patient was eventually discharged improved, with decreased dizziness. CONCLUSION Basal ganglia calcifications present with diverse manifestations and include seizures, mental deterioration and disorders of the cerebellar or extrapyramidal function. Treatment usually involves calcium and vitamin D supplementation. Marked clinical improvement usually results from treatment of hypoparathyroidism. Measurement and monitoring of serum calcium, phosphorus and intact PTH is warranted. REFERENCE: Ramen C. Basak. A Case Report of Basal Ganglia Calcification - A Rare Finding of Hypoparathyroidism. Oman Med J. 2009 Jul; 24(3): 220-222.

OR30-1 Safety and Efficacy of Recombinant Human Parathyroid Hormone 1-84 for the Treatment of Adults with Chronic Hypoparathyroidism: Six-Year Results of the RACE Study

RACE is an open-label study that assessed the long-term safety and efficacy of recombinant human parathyroid hormone 1-84 (rhPTH[1-84]) for the treatment of hypoparathyroidism in adults (ClinicalTrials.gov identifier NCT01297309). Patients initially received 25 or 50 µg/day of rhPTH(1-84) subcutaneously, once daily, with stepwise dose adjustments of 25 µg (up or down) to a maximum of 100 µg/day. rhPTH(1-84) could be titrated and oral calcium (Ca) and calcitriol doses adjusted at any time during the study to maintain albumin-corrected serum Ca levels in the target range of 8.0-9.0 mg/dL. A composite efficacy endpoint was the proportion of patients who achieved at least a 50% reduction from baseline (BL) in oral Ca dose (or Ca ≤500 mg/day) and at least a 50% reduction from BL in calcitriol dose (or calcitriol ≤0.25 µg/day), while normalizing or maintaining albumin-corrected serum Ca compared with BL value and not exceeding the upper limit of normal for the central laboratory. Here, we present 6-year safety and efficacy data with descriptive summary statistics (mean ± SD). The study cohort consisted of 49 patients enrolled at 12 US centers (mean age, 48.1±9.78 years; 81.6% female); data from 34 patients (69.4%) who completed 72 months (M72) of treatment with rhPTH(1-84) as of July 17, 2018 are presented here. Oral Ca and calcitriol doses were reduced by 40.4% and 72.2% at M72, respectively, and albumin-corrected serum Ca levels were maintained within the target range (BL, 8.4±0.70 mg/dL; M72, 8.4±0.68 mg/dL). At M72, 22 of 34 patients (64.7%) achieved the composite efficacy endpoint. Urinary Ca excretion declined from above-normal at BL to within the normal range (BL, 356.7±200.37 mg/24 h; M72, 213.2±128.82 mg/24 h). Mean serum creatinine levels remained stable (BL, 1.0±0.21 mg/dL; M72, 0.9±0.21 mg/dL), as did estimated glomerular filtration rate (eGFR; BL, 77.7±17.67 mL/min/1.73 m2; M72, 79.4±18.39 mL/min/1.73 m2). Serum phosphorus levels declined from above-normal at BL to within normal range (BL, 4.8±0.58 mg/dL; M72, 4.0±0.62 mg/dL); calcium-phosphorus product levels also declined (BL, 42.1±6.35 mg2/dL2; M72, 33.7±5.01 mg2/dL2). Treatment-emergent adverse events and treatment-emergent serious adverse events were reported in 98.0% and 26.5% of patients, respectively; no new safety concerns were identified. Continuous use of rhPTH(1-84) over 6 years resulted in a favorable safety profile, was effective, and improved key measurements of mineral homeostasis, notably normalization of urinary calcium. Disclosures: All of the authors disclose a relationship with Shire: advisory board member, JPB, MAL, MM, DMS, TJV; consultant, JPB, BLC, MAL, MM, DMS, TJV; grant recipient, JPB, DD, MM, MP, DMS, MLW; employee, H-ML, NS; research investigator, JPB, HB, JR, DMS, TJV, MLW, NBW; speaker, JPB, HB, MLW, NBW. Funding: Shire

MANAGEMENT OF ENDOCRINE DISEASE: Hypoparathyroidism in pregnancy: review and evidence-based recommendations for management.

Purpose Review calcium homeostasis in pregnancy and provide evidence-based best practice recommendations for the management of hypoparathyroidism in pregnancy. Methods We searched MEDLINE, EMBASE and Cochrane databases from January 2000 to April 1, 2018. A total of 65 articles were included in the final review. Conclusions During pregnancy, calcitriol levels increase by two- to-three-fold resulting in enhanced intestinal calcium absorption. The renal filtered calcium load increases leading to hypercalciuria. PTHrP production by the placenta and breasts increases by three-fold, and this may lower the doses of calcium and calcitriol required during pregnancy in mothers with hypoparathyroidism. The literature however describes a wide variation in the required doses of calcium and calcitriol during pregnancy in hypoparathyroid mothers, with some women requiring higher doses of calcitriol, whereas others require lower doses. Close monitoring is necessary as hypercalcemia in the mother may suppress the fetal parathyroid gland development. Also hypocalcemia in the mother is harmful as it may result in secondary hyperparathyroidism in the fetus. This may be associated with demineralization of the fetal skeleton and the development of intrauterine fractures. Inadequate treatment of hypoparathyroidism may also result in uterine contractions and an increased risk of miscarriage. Treatment targets during pregnancy are to maintain a low normal serum calcium. Calcium, calcitriol and vitamin D supplements are safe during pregnancy. Close monitoring of the mother with a multidisciplinary team is advised for optimal care. If calcium homeostasis is well controlled during pregnancy, most women with hypoparathyroidism have an uncomplicated pregnancy and give birth to healthy babies.

Recombinant parathyroid hormone for hypoparathyroidism in children: a narrative review.

The conventional management of hypoparathyroidism in children involves the use of calcium and vitamin D analogs. This therapy effec-tively increases the serum calcium levels but worsens hypercalciuria and its consequences such as nephrocalcinosis and renal insuffi-ciency. Although replacement with the missing parathyroid hormone (PTH) is ideal and available for more than 2 decades, the reported concerns of osteosarcoma prohibited its use in children with open epiphyses. Nevertheless, the data accumulated over the past several years suggests that the fears of bone malignancies were probably overstated. With an aim to review the available data on recombinant PTH (rhPTH) use, we performed a literature search using international databases and identified 15 studies involving approximately 70 children with hypoparathyroidism due to various etiologies who received rhPTH1-34 for durations between 1 day and 13.5 years. All the studies appear to indicate that rhPTH1-34 therapy is an effective short and long-term strategy for treatment of hypoparathyroidism with better metabolic control, lesser effects on renal function and improved quality of life as compared to conventional therapy. A more significant conclusion is the safety of long-term use of rhPTH1-34 with no observed adverse skeletal effects so far. However, all studies mention the importance of a continued surveillance for adverse effects in the treated patients. This narrative review discusses the experi-ence of rhPTH1-34 use exclusively in children.

Treatment of severe idiopathic hypoparathyroidism: a case report

Hypoparathyroidism is a rare disorder characterized by parathyroid hormone (PTH) insufficiency, the development of hypocalcemia and alteration of bone tissue remodeling.
 The goal of treatment is to normalize the indicators of calcium-phosphorus metabolism and leveling of clinical manifestations. Standard treatment of hypoparathyroidism consists of oral calcium and active forms of vitamin D, in doses necessary to maintain calcium levels at the lower limit of the reference interval.
 Nevertheless, treatment of the disease exerts certain difficulties in clinical practice. At the same time, compensation of the hypoparathyroidism is necessary to prevent ectopic calcification. Daily subcutaneous delivery of PTH (1–84) and PTH (1–34) has emerged as a promising therapeutic tool. However, its use should be restricted to patients insufficiently controlled with the standard treatment with active vitamin D and calcium.
 We present a clinical case of idiopathic hypoparathyroidism with severe clinical presentation of hypocalcaemia and ectopic calcification. Idiopathic hypoparathyroidism is a consequence of autoimmune destruction of the parathyroid glands and is exhibited by excluding all known causes of hypoparathyroidism.
 PTH (1–34) treatment allowed reducing the dose of calcium and vitamin D and achieving compensation of the disease.

Conventional Treatment of Hypoparathyroidism.

The treatment of hypoparathyroidism depends on the severity of hypocalcemia, how rapidly the hypocalcemia developed, and the symptomatology. Chronic hypoparathyroidism is usually treated with oral supplementations, including calcium, calcitriol, or other active vitamin D analogs, and at times, thiazide diuretics. Although the standard therapy can adequately control patients with this disease, sometimes very high doses are required to maintain serum calcium levels in the normal range, with poor compliance and risk of long-term complications.

Advances in the treatment of hypoparathyroidism with PTH 1-34.

Hypoparathyroidism is a rare disorder of calcium metabolism which is treated with calcium and vitamin D analogs. Although conventional therapy effectively raises serum calcium, it bypasses the potent calcium reabsorption effects of PTH on the kidney which leads to hypercalciuria and an increased risk of nephrocalcinosis and renal insufficiency. Twenty-five years ago, we launched the first systematic investigation into synthetic human PTH 1-34 replacement therapy in both adults and children. These studies led to our current understanding of the complex nature of PTH 1-34 therapy and to the challenges we still face in our pursuit of a safe and effective physiologic replacement therapy for hypoparathyroidism. The normalization and minimal fluctuation of serum and urine calcium levels were the primary management goals. As the frequency of PTH 1-34 injections increased, the total daily dose required to normalize calcium homeostasis decreased and episodes of hypercalcemia and hypercalciuria diminished, producing a more physiologic biochemical profile. Twice-daily injections achieved simultaneous normalization of serum and urine calcium levels in many patients but the persistent elevation of bone markers and the difficulty in reducing urine calcium to normal levels in the more severe cases, suggested an alternative to PTH 1-34 injections was needed. The studies with PTH 1-34 delivered by insulin pump represent an important advance in the management of hypoparathyroidism. PTH 1-34 delivered by insulin pump normalized serum and urine calcium and markers of bone turnover. Additionally, pump delivery of PTH 1-34 produced stable magnesium values within the normal range and reduced magnesium excretion. Currently, PTH 1-34 delivery by pump is the only alternative to PTH injections that has been tested in both adults and children and proven to achieve a physiologic biochemical profile.

Feasibility of autologous plasma gel for tonsil-derived stem cell therapeutics in hypoparathyroidism

Hypoparathyroidism is a deficiency of the parathyroid hormone (PTH) in the body. We previously reported the possibility of treating it using tonsil-derived mesenchymal stem cells (TMSCs) differentiated into PTH-releasing cells. The purpose of this study was to evaluate the feasibility of using autologous plasma gel as scaffold material in treatment of hypoparathyroidism with TMSC. We obtained plasma by venous sampling of autologous blood and centrifuged and fabricated the plasma gel using a sinusoidal pattern heating machine. After we created the hypoparathyroidism animal model, we administered undifferentiated TMSCs and TMSCs differentiated into parathyroid cells at each rat dorsum by intramuscular injection with and without the plasma gel. In the plasma gel groups, intact PTH was detected from on day 21 after TMSC injection; we did not detect intact PTH in the groups that were only transplanted with TMSCs during the entire experimental period. Serum calcium was higher and phosphorous was lower in the TMSC with plasma gel groups than in the groups with TMSCs alone. We detected PTH and chromogranin A in the TMSC-plasma gel-transplanted areas on immunohistochemistry and immunofluorescence stain. Plasma gel can be considered as a cell-delivery scaffold for treating hypoparathyroidism with tonsil-derived mesenchymal stem cells.

Development of a Novel Human Parathyroid Hormone Receptor 1 (hPTHR1) Agonist (CH5447240), a Potent and Orally Available Small Molecule for Treatment of Hypoparathyroidism

During the course of derivatization of HTS hit 4a, we have identified a novel small-molecule hPTHR1 agonist, 1-(3,5-dimethyl-4-(2-((2-((1 R,4 R)-4-methylcyclohexyl)-4-oxo-1,3,8-triazaspiro[4.5]dec-1-en-8-yl)sulfonyl)ethyl)phenyl)-1-methylurea (CH5447240, 14l). Compound 14l exhibited a potent in vitro hPTHR1 agonist effect with EC20 of 3.0 μM and EC50 of 12 μM and showed excellent physicochemical properties, such as high solubility in fasted state simulated intestinal fluid and good metabolic stability in human liver microsomes. Importantly, 14l showed 55% oral bioavailability and a significantly elevated serum calcium level in hypocalcemic model rats.

Treatment of hypoparathyroidism with the recombinant parathyroid hormone (1—34) in a female patient with type 1 autoimmune polyglandular syndrome: the first experience in the Russian Federation

Hypoparathyroidism is one of the major symptoms of type 1 autoimmune polyglandular syndrome. Currently, vitamin D preparations are the treatment of choice for hypoparathyroidism of any etiology. The treatment with these medications is quite effective to normalize and maintain calcium level. The world experience in application of the recombinant parathyroid hormone for the treatment of hypoparathyroidism is very limited and indications for its use are not determined. However, there are increasingly more publications reflecting the experience in treatment of patients with hypoparathyroidism with the parathyroid hormone.
 Type 1 autoimmune polyglandular syndrome is characterized by multiform clinical manifestations and for this reason it is often difficult to achieve compensation using replacement therapy. Autoimmune enteropathy often develops, which leads to severe malabsorption of nutrients and drugs in the intestine and inefficient replacement therapy, which necessitates a special approach and additional recommendations for the treatment of these patients with combined pathology of several organs and systems. This article describes the first Russian experience in the use of teriparatide pump therapy in a female patients with hypoparathyroidism as a part of severe autoimmune polyglandular syndrome.

Diagnosis and treatment of hypoparathyroidism: a position statement from the Brazilian Society of Endocrinology and Metabolism.

Objective To present an update on the diagnosis and treatment of hypoparathyroidism based on the most recent scientific evidence. Materials and methods The Department of Bone and Mineral Metabolism of the Sociedade Brasileira de Endocrinologia e Metabologia (SBEM; Brazilian Society of Endocrinology and Metabolism) was invited to prepare a document following the rules set by the Guidelines Program of the Associação Médica Brasileira (AMB; Brazilian Medical Association). Relevant papers were retrieved from the databases MEDLINE/PubMed, LILACS, and SciELO, and the evidence derived from each article was classified into recommendation levels according to scientific strength and study type. Conclusion An update on the recent scientific literature addressing hypoparathyroidism is presented to serve as a basis for the diagnosis and treatment of this condition in Brazil.

Repurposing a novel parathyroid hormone analogue to treat hypoparathyroidism.

Human parathyroid hormone (PTH) is critical for maintaining physiological calcium homeostasis and plays an important role in the formation and maintenance of the bone. Full-length PTH and a truncated peptide form are approved for treatment of hypoparathyroidism and osteoporosis respectively. Our initial goal was to develop an improved PTH therapy for osteoporosis, but clinical development was halted. The novel compound was then repurposed as an improved therapy for hypoparathyroidism. A longer-acting form of PTH was synthesised by altering the peptide to increase cell surface residence time of the bound ligand to its receptor. In vitro screening identified a compound, which was tested in an animal model of osteoporosis before entering human trials. This compound was subsequently tested in two independent animal models of hypoparathyroidism. The peptide identified, LY627-2K, exhibited delayed internalization kinetics. In an ovariectomy-induced bone loss rat model, LY627-2K demonstrated improved vertebral bone mineral density and biomechanical properties at skeletal sites and a modest increase in serum calcium. In a Phase I clinical study, dose-dependent increases in serum calcium were reproduced. These observations prompted us to explore a second indication, hypoparathyroidism. In animal models of this disease, LY627-2K restored serum calcium, comparing favourably to treatment with wild-type PTH. We summarize the repositioning of a therapeutic candidate with substantial preclinical and clinical data. Our results support its repurposing and continued development, from a common indication (osteoporosis) to a rare disease (hypoparathyroidism) by exploiting a shared molecular target. This article is part of a themed section on Inventing New Therapies Without Reinventing the Wheel: The Power of Drug Repurposing. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v175.2/issuetoc.

Impact of intercurrent illness on calcium homeostasis in children with hypoparathyroidism: a case series.

BackgroundHypoparathyroidism is characterised by hypocalcaemia, and standard management is with an active vitamin D analogue and adequate oral calcium intake (dietary and/or supplements). Little is described in the literature about the impact of intercurrent illnesses on calcium homeostasis in children with hypoparathyroidism.MethodsWe describe three children with hypoparathyroidism in whom intercurrent illnesses led to hypocalcaemia and escalation of treatment with alfacalcidol (1-hydroxycholecalciferol) and calcium supplements.ResultsThree infants managed with standard treatment for hypoparathyroidism (two with homozygous mutations in GCMB2 gene and one with Sanjad-Sakati syndrome) developed symptomatic hypocalcaemia (two infants developed seizures) following respiratory or gastrointestinal illnesses. Substantial increases in alfacalcidol doses (up to three times their pre-illness doses) and calcium supplementation were required to achieve acceptable serum calcium concentrations. However, following resolution of illness, these children developed an increase in serum calcium and hypercalciuria, necessitating rapid reduction to pre-illness dosages of alfacalcidol and oral calcium supplementation.ConclusionIntercurrent illness may precipitate symptomatic hypocalcaemia in children with hypoparathyroidism, necessitating increase in dosages of alfacalcidol and calcium supplements. Close monitoring is required on resolution of the intercurrent illness, with timely reduction of dosages of active analogues of vitamin D and calcium supplements to prevent hypercalcaemia, hypercalciuria and nephrocalcinosis.

Sustained release of parathyroid hormone via in situ cross-linking gelatin hydrogels improves the therapeutic potential of tonsil-derived mesenchymal stem cells for hypoparathyroidism.

Biomimetic parathyroid regeneration with sustained release of parathyroid hormone (PTH) into the blood stream is a considerable challenge in hypoparathyroidism treatment. We recently reported that tonsil-derived mesenchymal stem cells (TMSCs), if these cells were both differentiated in vitro before implantation and incorporated into a scaffold Matrigel, are a good cell source for parathyroid regeneration in a parathyroidectomized (PTX) animal model. Here, we present a new strategy for improved clinical application that enhances the sustained release of PTH by controlling mechanical stiffness using in situ-forming gelatin-hydroxyphenyl propionic acid (GH) hydrogels (GHH). Differentiated TMSCs (dTMSCs) embedded in a GHH with a strength of 4.4kPa exhibited the best sustained release of PTH and were the most effective in hypoparathyroidism treatment, showing improved blood calcium homeostasis compared with Matrigel-embedded dTMSCs. Interestingly, undifferentiated control TMSCs (cTMSCs) also released PTH in a sustained manner if incorporated into GHH. Collectively, these findings may establish a new paradigm for parathyroid regeneration that could ultimately evolve into an improved clinical application. Copyright © 2017 John Wiley & Sons, Ltd.

Update on recent progress in vitamin D research. Vitamin D treatment for hypoparathyroidism.

The patients with hypoparathyroidism have been treated with active vitamin D(ie, alfacalcidol and calcitriol). Parathyroid hormone(PTH)increases extracellular calcium concentration partly through the activation of vitamin D, and active vitamin D corrects hypocalcemia mainly by increasing intestinal calcium abosorption. PTH coordinately increases blood calcium level with vitamin D in bone and kidney, however, renal tubular reabsorption of calcium is regulated by PTH-dependent mechanism. Hypercalciuria is an complication of long-term vitamin D treatment for PTH-deficient hypoparathyroidism.

Efficacy of Teriparatide in Patients with Hypoparathyroidism: A Prospective, Open-label Study.

Context:Conventional treatment of hypoparathyroidism with calcium, Vitamin D analogs, and thiazide diuretics is often suboptimal, and these patients have poor quality of life. Teriparatide (parathyroid hormone 1–34 [PTH (1–34)]), an amide of PTH, is widely available for the use in osteoporosis; however, its use in hypoparathyroidism is limited.Aims:The aim of this study is to evaluate the efficacy of PTH (1–34) in the treatment of patients with hypoparathyroidism.Settings and Design:This was a prospective, open-label interventional study in a tertiary care hospital of Indian Armed Forces.Subjects and Methods:All patients with hypoparathyroidism presented to the endocrinology outpatient department were included and were exhibited injection PTH (1–34) 20 μg twice daily that was gradually reduced to 10 μg twice daily along with calcium, active Vitamin D (alfacalcidol), and hydrochlorothiazide. Oral calcium and alfacalcidol doses were also reduced to maintain serum calcium within normal range. The quality of life (QOL) score was calculated using RAND 36 QOL questionnaire at baseline and termination of the study.Statistical Analysis Used:Paired t-test was used to calculate pre- and post-treatment variables.Results:Eight patients (two males) were included in this study having mean age of 35.8 years. PTH (1–34) treatment led to the improvement in serum calcium (6.81–8.84 mg/dl), phosphorous (5.8–4.2 mg/dl), and 24 h urinary calcium excretion (416–203.6 mg). Parameters of QOL showed the improvement in overall QOL, physical performance, energy, and fatigue scores. No major adverse events were noted.Conclusions:Treatment of hypoparathyroidism with PTH (1–34) leads to improvement in calcium profile, reduction in hypercalciuria, and improvement in QOL, whereas it is safe and well tolerated.

Hypoparathyroidism: etiology, clinical manifestation, current diagnostics and treatment

Parathyroid hormone (PTH) is the main regulator of calcium and phosphorus metabolism. PTH deficiency or tissue resistance to its effects results in hypoparathyroidism characterized by low serum calcium and elevated serum phosphate levels. The most common is post-operative hypoparathyroidism caused by an inadvertent damage or removal of the parathyroid glands, deterioration of blood supply to the neck region, most often during thyroid surgery. The second common form of the disease is the autoimmune one related with immune destruction of parathyroid cells. Less frequent causes of hypoparathyroidism include a variety of genetic syndromes, mitochondrial genome defects, and hypomagnesemia. The main signs and symptoms of hypoparathyroidism are related to hypocalcaemia and hyperphosphatemia land result in increased neuromuscular irritability and general autonomic reactivity, with finger and toe tingling, muscle cramps, tonic seizures, laryngo- and bronchospasm, and neurosis. These symptoms are closely associated with serum calcium levels; their severity depends on the degree of hypocalcaemia. Laboratory parameters confirming the diagnosis of hypoparathyroidism are hypocalcaemia, hyperphosphatemia, and reduced serum PTH. Treatment of hypoparathyroidism involves management of hypocalcaemic crisis and maintenance therapy. Acute hypocalcaemia, a potentially life-threatening condition, is treated as an emergency with intravenous calcium combined with oral calcium and active vitamin D. Standard chronic treatment for hypoparathyroidism is based on oral calcium and active metabolites of vitamin D / vitamin D analogs and is aimed at the balance between optimal low-normal serum calcium concentrations and normocalciuria. Worsening hypercalciuria is often underestimated by specialists, although it can cause severe renal problems, such as nephrocalcinosis and neprolithiasis. Hypoparathyroidism is one of the few endocrine deficiencies for which replacement treatment with recombinant PTH is not widely used. Replacement therapy with recombinant human PTH is a promising area, especially in severe clinical cases, refractory to conventional treatment.

CLINICAL CASE OF TERIPARATIDE USE FOR THE TREATMENT OF POSTOPERATIVE HYPOPARATHYROIDISM WITH UNCONTROLLED HYPOCALCEMIA COMBINED WITH SEVERE OSTEOPOROSIS

The development of postsurgical hypoparathyroidism is the most frequent complication of thyroidectomy and radical surgical procedures on the neck. Hypoparathyroidism is a disorder characterized by hypocalcemia, parathyroid hormone (PTH) deficiency, and abnormal bone remodeling. Standard treatment of hypoparathyroidism consists of oral calcium and active forms of vitamin D. However, some patients fail to achieve the normalization of calcium levels with this therapy. We present a clinical case of postsurgical hypoparathyroidism with severe clinical presentation of hypocalcaemia treated with recombinant human PTH 1-34 - teriparatide.

Identification of an orally active small-molecule PTHR1 agonist for the treatment of hypoparathyroidism.

Parathyroid hormone (PTH) is essential for calcium homeostasis and its action is mediated by the PTH type 1 receptor (PTHR1), a class B G-protein-coupled receptor. Hypoparathyroidism and osteoporosis can be treated with PTH injections; however, no orally effective PTH analogue is available. Here we show that PCO371 is a novel, orally active small molecule that acts as a full agonist of PTHR1. PCO371 does not affect the PTH type 2 receptor (PTHR2), and analysis using PTHR1–PTHR2 chimeric receptors indicated that Proline 415 of PTHR1 is critical for PCO371-mediated PTHR1 activation. Oral administration of PCO371 to osteopenic rats provokes a significant increase in bone turnover with limited increase in bone mass. In hypocalcemic rats, PCO371 restores serum calcium levels without increasing urinary calcium, and with stronger and longer-lasting effects than PTH injections. These results strongly suggest that PCO371 can provide a new treatment option for PTH-related disorders, including hypoparathyroidism.

Microencapsulation of Parathyroid Cells for the Treatment of Hypoparathyroidism.

Cell encapsulation is an alternative to avoid rejection of grafted tissue, thus bringing an interesting alternative in cell therapy. It is particularly relevant in ailments where only the implant of small quantities of tissues is warranted. In such circumstances, the use of immunosuppressive therapy in patients implanted with tissues from donors is debatable, yet unavoidable at present in order to prevent rejection and/or sensitization of the host to the tissue, in turn jeopardizing the success of successive implants. Hence, a new line of thought, which aims to provide an immunoprivileged site for the grafted tissue, while at the same time insure its nutrition, as well as its survival and continued function, appears as a most attractive possibility. To achieve these goals, cells or tissues harvested for transplant could be encapsulated in biologically compatible matrices. Among the matrices currently in existence, sodium alginate is the most widely used polymer for tissue encapsulation.In the present chapter, we present a technique used to encapsulate parathyroid tissue, for use as cell transplant therapy in patients with secondary hypoparathyroidism. With this procedure, implanted tissue survives and remains functional for up to 18 months.