Allosteric modulation and G-protein selectivity of the Ca2+-sensing receptor.

The calcium-sensing receptor (CaSR) is a family C G-protein-coupled receptor1 (GPCR) that has a central role in regulating systemic calcium homeostasis2,3. Here we use cryo-electron microscopy and functional assays to investigate the activation of human CaSR embedded in lipid nanodiscs and its coupling to functional Gi versus Gq proteins in the presence and absence of the calcimimetic drug cinacalcet. High-resolution structures show that both Gi and Gq drive additional conformational changes in the activated CaSR dimer to stabilize a more extensive asymmetric interface of the seven-transmembrane domain (7TM) that involves key protein-lipid interactions. Selective Gi and Gq coupling by the receptor is achieved through substantial rearrangements of intracellular loop 2 and the C terminus, which contribute differentially towards the binding of the two G-protein subtypes, resulting in distinct CaSR-G-protein interfaces. The structures also reveal that natural polyamines target multiple sites on CaSR to enhance receptor activation by zipping negatively charged regions between two protomers. Furthermore, we find that the amino acid L-tryptophan, a well-known ligand of CaSR extracellular domains, occupies the 7TM bundle of the G-protein-coupled protomer at the same location as cinacalcet and other allosteric modulators. Together, these results provide a framework for G-protein activation and selectivity by CaSR, as well as its allosteric modulation by endogenous and exogenous ligands.

Repurposing cinacalcet suppresses multidrug-resistant Staphylococcus aureus by disruption of cell membrane and inhibits biofilm by targeting IcaR.

BACKGROUND: MDR Staphylococcus aureus infections, along with the severity of biofilm-associated infections, continue to threaten human health to a great extent. It necessitates the urgent development of novel antimicrobial and antibiofilm agents. OBJECTIVES: To reveal the mechanism and target of cinacalcet as an antibacterial and antimicrobial agent for S. aureus. METHODS: Screening of non-antibiotic drugs for antibacterial and antibiofilm properties was conducted using a small-molecule drug library. In vivo efficacy was assessed through animal models, and the antibacterial mechanism was studied using quantitative proteomics, biochemical assays, LiP-SMap, BLI detection and gene knockout techniques. RESULTS: Cinacalcet, an FDA-approved drug, demonstrated antibacterial and antibiofilm activity against S. aureus, with less observed development of bacterial resistance. Importantly, cinacalcet significantly improved survival in a pneumonia model and bacterial clearance in a biofilm infection model. Moreover, the antibacterial mechanism of cinacalcet mainly involves the destruction of membrane-targeted structures, alteration of energy metabolism, and production of reactive oxygen species (ROS). Cinacalcet was found to target IcaR, inhibiting biofilm formation through the negative regulation of IcaADBC. CONCLUSIONS: The findings suggest that cinacalcet has potential for repurposing as a therapeutic agent for MDR S. aureus infections and associated biofilms, warranting further investigation.

The Effects of Parathyroidectomy vs Medical Treatments for Secondary Hyperparathyroidism in Patients Undergoing Dialysis: A Meta-Analysis.

OBJECTIVE: The management of secondary hyperparathyroidism in patients undergoing dialysis is debated, with uncontrolled parathyroid hormone (PTH) levels becoming more common despite the expanded use of medical treatments like cinacalcet. This study examines the clinical benefits of parathyroidectomy vs medical treatment in reducing mortality and managing key laboratory parameters in patients undergoing dialysis. METHODS: PubMed, Embase, Cochrane, Scopus, and Web of Science databases were searched for cohort studies or randomized controlled trials published before August 18, 2023. We included studies with comparative arms, specifically medical treatment vs surgical intervention. Patients with a history of kidney transplant were excluded. Outcomes were analyzed using hazard ratios (HRs) for mortality and weighted mean differences (WMD) for laboratory parameters. RESULTS: Twenty-three studies involving 24 398 patients were analyzed. The pooled meta-analysis has shown a significant reduction in all-cause (HR, 0.47; 95% confidence interval [CI], 0.35-0.61) and cardiovascular mortality (HR, 0.58; 95% CI, 0.40-0.84) for parathyroidectomy vs medical treatments. Subgroup analysis showed that parathyroidectomy was associated with a greater reduction in mortality in patients with a PTH level over 585 pg/mL (HR, 0.37; 95% CI, 0.24-0.58). No mortality difference was found when all patients in the medical group received cinacalcet alongside standard medical treatment (HR, 1.02; 95% CI, 0.49-2.11). Parathyroidectomy also led to a larger decrease in PTH (WMD, 1078 pg/mL; 95% CI, 587-1569), calcium (WMD, 0.86 mg/dL; 95% CI, 0.43-1.28), and phosphate (WMD, 0.74 mg/dL; 95% CI, 0.32-1.16). CONCLUSION: Parathyroidectomy may offer a survival advantage compared to medical management in patients with severe secondary hyperparathyroidism.

Comparative efficacy of sodium thiosulfate, bisphosphonates, and cinacalcet for the treatment of vascular calcification in patients with haemodialysis: a systematic review and network meta-analysis.

BACKGROUND: Up to now, there is no unequivocal intervention to mitigate vascular calcification (VC) in patients with hemodialysis. This network meta-analysis aimed to systematically evaluate the clinical efficacy of sodium thiosulfate, bisphosphonates, and cinacalcet in treating vascular calcification. METHODS: A comprehensive study search was performed using PubMed, Web of Science, the Cochrane Library, EMBASE and China National Knowledge Internet (CNKI) to collect randomized controlled trials (RCTs) of sodium thiosulfate, bisphosphonates, and cinacalcet for vascular calcification among hemodialysis patients. Then, network meta-analysis was conducted using Stata 17.0 software. RESULTS: In total, eleven RCTs including 1083 patients were qualified for this meta-analysis. We found that cinacalcet (SMD - 0.59; 95% CI [-0.95, -0.24]) had significant benefit on vascular calcification compared with conventional therapy, while sodium thiosulfate or bisphosphonates did not show such efficiency. Furthermore, as for ranking the efficacy assessment, cinacalcet possessed the highest surface under the cumulative ranking curve (SUCRA) value (88.5%) of lessening vascular calcification and was superior to sodium thiosulfate (50.4%) and bisphosphonates (55.4%). Thus, above results suggested that cinacalcet might be the most promising drug for vascular calcification treatment in hemodialysis patients. Mechanistically, our findings illustrated that cinacalcet reduced serum calcium (SMD - 1.20; 95% CI [-2.08, - 0.33]) and showed the tendency in maintaining the balance of intact Parathyroid Hormone (iPTH) level. CONCLUSIONS: This network meta-analysis indicated that cinacalcet appear to be more effective than sodium thiosulfate and bisphosphonates in mitigating vascular calcification through decreasing serum calcium and iPTH. And cinacalcet might be a reasonable option for hemodialysis patients with VC in clinical practice. SYSTEMATIC REVIEW REGISTRATION: [ http://www.crd.york.ac.uk/PROSPERO ], identifier [CRD42022379965].

Oral cinacalcet administration decreases serum ionized calcium and parathyroid hormone concentrations in healthy dogs.

Cinacalcet is an oral calcimimetic that has potential to non-invasively treat primary hyperparathyroidism in dogs (Canis lupis familiaris). There is minimal data assessing its efficacy in dogs. This study aimed to determine whether a single dose of cinacalcet decreases serum ionized calcium (iCa), total calcium (tCa), and parathyroid hormone (PTH) concentrations. Twelve dogs received a median dose of 0.49 mg/kg (range 0.30-0.69 mg/kg) cinacalcet per os. Venous blood samples were collected at time 0 (before cinacalcet administration), 3, 8, and 24 h following cinacalcet administration. PTH, iCa, and tCa concentrations were measured at each time point and compared to 0 hour concentrations. A significant (50%) decrease in serum PTH occurred at 3 h with a median PTH of 4.6 pmol/L (range 2.7-10.8) at baseline and 1.65 pmol/L (range 0.5-14.7) at 3 h; p = .005. A significant, but not clinically relevant, decrease in serum iCa from a median baseline of 1.340 mmol/L (range 1.32-1.41) to a 3 h median of 1.325 mmol/L (range 1.26-1.39), p = .043, was also observed. tCa concentrations were not different. This study showed that a single dose of cinacalcet leads to transient decreases in iCa and PTH concentrations in healthy dogs.

Pharmaceutical Management of Secondary Hyperparathyroidism and the Role of Surgery: A 5-Year Retrospective Study.

Background and Objectives: Secondary hyperparathyroidism (SHPT) poses a common condition among patients with chronic kidney disease (CKD) due to the chronic stimulation of the parathyroid glands as a result of persistently low calcium levels. As a first option for medical treatment, vitamin D receptor analogs (VDRAs) and calcimimetic agents are generally used. Apart from cinacalcet, which is orally taken, in recent years, another calcimimetic agent, etelcalcetide, is being administered intravenously during dialysis. Materials and Methods: In a 5-year retrospective study between 2018 and 2023, 52 patients undergoing dialysis were studied. The aim of this study is to highlight the possible effects and/or benefits that intravenously administered calcimimetic agents have on CKD patients. A total of 34 patients (65.4%) received cinacalcet and etelcalcetide while parathormone (PTH) and calcium serum levels were monitored on a monthly basis. Results: A total of 29 out of 33 patients (87.9%) that received treatment with etelcalcetide showed a significant decrease in PTH levels, which rose up to 57% compared to the initial values. None of the included patients needed to undergo parathyroidectomy (PTx) due to either extremely high and persistent PTH levels or severe side effects of the medications. It is generally strongly advised that parathyroidectomies should be performed by an expert surgical team. In recent years, a significant decrease in parathyroidectomies has been recorded globally, a fact that is mainly linked to the constantly wider use of new calcimimetic agents. This decrease in parathyroidectomies has resulted in an important decrease in complications occurring in cervical surgeries (e.g., perioperative hemorrhage and nerve damage). Conslusions: Despite the fact that these surgical complications cannot be easily compared to the pharmaceutical side effects, the recorded decrease in parathyroidectomies is considered to be notable, especially in cases of relapse where a difficult reoperation would be considered based on previously published guidelines.

Preparation of UV-cured cellulose nanocrystal-filled epoxidized natural rubber and its application in a triboelectric nanogenerator.

Cellulose nanocrystal (CNC) is an abundant biopolymer possessing high strength and biodegradability. In the present work, the extraction of CNCs from Napier grass stems was carried out. The CNCs were subsequently modified by maleic anhydride, called M-CNC, before being incorporated into the epoxidized natural rubber (ENR). The compounds were later cured by ultraviolet (UV) irradiation under various conditions. The obtained optimum condition was then used to fabricate the biocomposites filled with various CNC and M-CNC loadings for triboelectric nanogenerator (TENG) performance measurements. Output voltage and current increased continuously with increasing filler loading. Regardless of the filler type, an increase in filler loading enhanced TENG output. ENR/M-CNC exhibited a superior TENG output to ENR/CNC due to the greater electron transfer capability of the biocomposites, as proven by the reduction in the ionization potential (IP) value obtained from the quantum calculation. In this study, ENR/M-CNC5 exhibited the maximum output voltage (80.3 V), current (7.4 µA), and power density (1.32 W/m2) at a load resistance of 9 MΩ.

Cellulose nanocrystals boosted hydrophobically associated self-healable conductive hydrogels for the application of strain sensors and electronic devices.

Currently, hydrogel-based flexible devices become hot areas for scientists in the field of electronic devices, artificial intelligence, human motion detection, and electronic skin. These devices show responses to external stimuli (mechanical signals) and convert them into electrical signals (resistance, current, and voltage). However, the applications of the hydrogel-based sensor are hampered due to low mechanical properties, high time response, low fatigue resistance, low self-healing nature, and low sensing range. Herein, a strain sensing conductive hydrogel constructed from the CNCs (cellulose nanocrystal) reinforced, in which acrylamide and butyl acrylate work as hydrophilic and hydrophobic monomers respectively. The incorporation of CNCs in the polymeric system has a direct effect on their mechanical properties. The hydrogel having a high amount of CNCs (C4), its fracture stress and fracture strain reached 371.2 kPa and 2108 % respectively as well as self-healing of C4 hydrogel Broke at 499 % strain and bore 197 kPa stress. The elastic behavior of the hydrogels was confirmed by the rheological parameter frequency sweep and strain amplitude. Besides this our designed hydrogel shows an excellent response to deformation with conductivity 420 mS m-1, shows response to small strain (10 %) and large (400 %) strain, and has excellent anti-fatigue resistance with continuous stretching for 700 s at 300 % strain, with 140 msec response time, and gauge factor 7.4 at 750 % strain. The C4 hydrogel can also work as electronic skin when it is applied to different joints like the finger, elbow, neck, etc. The prepared hydrogel can also work as an electronic pen when it is worn to a plastic pen cover.

Hereditary vitamin D resistant rickets (HVDRR) case series: phenotype, genotype, conventional treatment, and adjunctive cinacalcet therapy.

INTRODUCTION: Hereditary vitamin D resistant rickets (HVDRR) is a rare autosomal recessive disorder marked by end-organ resistance of 1,25-dihydroxyvitamin D secondary to various mutations in the vitamin D receptor gene. The currently accepted treatment modality involves bypassing the affected receptors in the gut with high-dose intravenous calcium. In a few limited case reports, cinacalcet, a calcimimetic, has been used as an adjunctive therapy. MATERIAL AND METHODS: Retrospective chart reviews were conducted to collect the clinical and biochemical data of 8 patients with HVDRR from 5 Saudi families. Four patients received only high-dose calcium, while the remaining 4 received adjuvant cinacalcet. Serum chemistry and PTH levels were measured before and during cinacalcet treatment. Gene sequencing was performed to identify the disease-causing mutation. RESULTS: All 8 patients exhibited alopecia and secondary hyperparathyroidism. Other clinical and biochemical features of rickets were present to varying degrees. Genetic analysis revealed 3 distinct mutations: a ligand-binding domain mutation in 3 unrelated patients, a ligand-binding domain mutation in 2 sisters, and a missense DNA-binding domain mutation in 3 brothers. While the overall response to therapy was variable, none of the 4 patients who received adjunctive cinacalcet developed hypocalcaemia, and there was some initial promise in improving serum PTH levels. CONCLUSIONS: This series provides new insight into the clinical and biochemical characteristics as well as treatment responses in Saudi children with HVDRR. The findings suggest that cinacalcet is a safe and potentially valuable adjuvant in this understudied population; however, further research is required to verify these results.

Combination of the CRAC Channel Inhibitor CM4620 and Galactose as a Potential Therapy for Acute Pancreatitis.

Acute pancreatitis (AP) is a life-threatening inflammatory disease with no specific therapy. Excessive cytoplasmic Ca2+ elevation and intracellular ATP depletion are responsible for the initiation of AP. Inhibition of Ca2+ release-activated Ca2+ (CRAC) channels has been proposed as a potential treatment, and currently, a novel selective CRAC channel inhibitor CM4620 (Auxora, CalciMedica) is in Phase 2b human trials. While CM4620 is on track to become the first effective treatment for AP, it does not produce complete protection in animal models. Recently, an alternative approach has suggested reducing ATP depletion with a natural carbohydrate galactose. Here, we have investigated the possibility of using the smallest effective concentration of CM4620 in combination with galactose. Protective effects of CM4620, in the range of 1-100 n m, have been studied against necrosis induced by bile acids, palmitoleic acid, or l-asparaginase. CM4620 markedly protected against necrosis induced by bile acids or asparaginase starting from 50 n m and palmitoleic acid starting from 1 n m. Combining CM4620 and galactose (1 m m) significantly reduced the extent of necrosis to near-control levels. In the palmitoleic acid-alcohol-induced experimental mouse model of AP, CM4620 at a concentration of 0.1 mg/kg alone significantly reduced edema, necrosis, inflammation, and the total histopathological score. A combination of 0.1 mg/kg CM4620 with galactose (100 m m) significantly reduced further necrosis, inflammation, and histopathological score. Our data show that CM4620 can be used at much lower concentrations than reported previously, reducing potential side effects. The novel combination of CM4620 with galactose synergistically targets complementary pathological mechanisms of AP.

Glutathione-Based Photoaffinity Probe Identifies Caffeine as a Positive Allosteric Modulator of the Calcium-Sensing Receptor.

The calcium-sensing receptor (CaSR), abundantly expressed in the parathyroid gland and kidney, plays a central role in calcium homeostasis. In addition, CaSR exerts multimodal roles, including inflammation, muscle contraction, and bone remodeling, in other organs and tissues. The diverse functions of CaSR are mediated by many endogenous and exogenous ligands, including calcium, amino acids, glutathione, cinacalcet, and etelcalcetide, that have distinct binding sites in CaSR. However, strategies to evaluate ligand interactions with CaSR remain limited. Here, we developed a glutathione-based photoaffinity probe, DAZ-G, that analyzes ligand binding to CaSR. We showed that DAZ-G binds to the amino acid binding site in CaSR and acts as a positive allosteric modulator of CaSR. Oxidized and reduced glutathione and phenylalanine effectively compete with DAZ-G conjugation to CaSR, while calcium, cinacalcet, and etelcalcetide have cooperative effects. An unexpected finding was that caffeine effectively competes with DAZ-G's conjugation to CaSR and acts as a positive allosteric modulator of CaSR. The effective concentration of caffeine for CaSR activation (<10 µM) is easily attainable in plasma by ordinary caffeine consumption. Our report demonstrates the utility of a new chemical probe for CaSR and discovers a new protein target of caffeine, suggesting that caffeine consumption can modulate the diverse functions of CaSR.

Chronic Cinacalcet improves skin flap survival in rats: the suggested role of the nitric oxide pathway.

Cinacalcet is a calcimimetic medicine that has been used to treat secondary hyperparathyroidism and parathyroid cancer. Various studies have proposed the positive role of calcium and its receptor in skin wound healing. Furthermore, Cinacalcet interacts with other skin repair-related mechanisms, including inflammation and nitric oxide pathways. The present study evaluated the effect of Cinacalcet on the random-pattern skin flap survival. Eighty-four Wistar male rats were used. Multiple doses of Cinacalcet (30, 3, 1, 0.3, and 0.05 mg/kg) were used in 3 different routes of administration before the surgery. Histopathological evaluations, quantitative assessment of IL-6, TNF-α, and nitric oxide (NO), and the expression of calcium-sensing receptor (CaSR) and E-cadherin were evaluated in the skin tissue. To assess the role of NO, a NO synthase inhibitor, N-nitro-L-arginine methyl ester hydrochloride (L-NAME), was used, and histopathological effects were investigated. Cinacalcet pretreatment at the IP chronic 1 mg/kg dose significantly increased the skin flap survival rate and enhanced the NO tissue level compared to the control. However, the administration of L-NAME abolished its protective effects. IP Chronic 1 mg/kg of Cinacalcet could also decline the levels of IL-6 and TNF-α and also increase the expression of CaSR and E-cadherin in the flap tissue compared with the control group. Chronic Cinacalcet at 1 mg/kg could improve skin flap survival, probably mediated by the CaSR, NO, and inflammation-related pathways.

Familial hypocalciuric hypercalcemia as a differential diagnosis of primary hyperparathyroidism with negative images / Hipercalcemia hipocalciúrica familiar como diagnóstico diferencial de hiperparatiroidismo primario con imágenes negativas / Hipercalcemia hipocalciúrica familiar como diagnóstico diferencial de hiperparatireoidismo primário com imagens negativas

Introduction. Familial hypocalciuric hypercalcemia is a rare inherited calcium metabolism disorder in which an alteration of the parathyroid hormone secretion set-point causes hypercalcemia with relative hypocalciuria. Some data suggest that its prevalence is around 74.1 per 100,000 inhabitants. Often, patients are asymptomatic. However, they can develop mild symptoms and an overactive parathyroid adenoma, its main differential diagnosis. The objective was to describe a patient's case and highlight the importance of clinical suspicion and diagnosis to avoid unnecessary surgical neck explorations for parathyroid adenomas. Case report. This is the case of a 40-year-old man with a biochemical profile compatible with primary hyperparathyroidism with anatomical and functional images negative for adenoma and a calcium/creatinine clearance ratio below 0.001, considering familial hypocalciuric hypercalcemia. Genetic studies evidence a mutation in the calcium sensor receptor gene and confirm the diagnosis. Discussion. Familial hypocalciuric hypercalcemia's main differential diagnosis is an overactive parathyroid adenoma. For both, mild or no symptoms may be present; serum calcium exceeds the upper limit, and parathormone is more than 25pg/ml. The calcium/creatinine clearance ratio should be used to differentiate one from the other and avoid unnecessary surgical neck explorations. Besides the lack of information on this topic, evidence supports the use of calcimimetics to treat symptomatic hypercalcemia. Conclusions. Patients with mild hypercalcemia with parathyroid hormone readings above 25pg/ml and a calcium/creatinine clearance ratio below 0.001, or patients with primary hyperparathyroidism with negative imaging, should not undergo surgical neck explorations. In these cases, familial hypocalciuric hypercalcemia is a reliable diagnosis; Cinacalcet may be administered in cases of symptomatic hypercalcemia.

Introducción. La hipercalcemia hipocalciúrica familiar es un trastorno hereditario poco común del metabolismo del calcio en donde una alteración del punto de ajuste de la secreción de hormona paratiroidea ocasiona hipercalcemia con hipocalciuria relativa. Algunos datos sugieren que su prevalencia es de alrededor de 74.1 por 100,000 habitantes. Los pacientes muchas veces son asintomáticos. Sin embargo, pueden desarrollar síntomas leves y un adenoma paratiroideo hiperactivo, que representa su principal diagnóstico diferencial. El objetivo fue describir el caso de un paciente y resaltar la importancia de la sospecha y el diagnóstico clínico para evitar exploraciones quirúrgicas cervicales innecesarias en búsqueda de adenomas paratiroideos. Reporte de caso. Este es el caso de un hombre de 40 años con un perfil bioquímico compatible con hiperparatiroidismo primario, con imágenes anatómicas y funcionales negativas para adenoma, además de una relación de depuración de calcio/creatinina menor a 0.001, con consideración de hipercalcemia hipocalciúrica familiar. Los estudios genéticos evidencian una mutación en el gen del receptor sensor del calcio y confirman el diagnóstico. Discusión. El principal diagnóstico diferencial de la hipercalcemia hipocalciúrica familiar es un adenoma paratiroideo hiperactivo. En ambos casos, es posible que no haya síntomas o que estos sean leves; el calcio sérico excede al límite superior, y la paratohormona es mayor de 25pg/ml. Se debe usar la relación de depuración de calcio/creatinina para diferenciar entre estas patologías y evitar exploraciones quirúrgicas cervicales innecesarias. Aparte de la falta de información sobre este tema, la evidencia apoya el uso de calciomiméticos para tratar la hipercalcemia sintomática. Conclusiones. Los pacientes con hipercalcemia leve, con valores de hormona paratiroidea mayores de 25pg/ml y con una relación de depuración de calcio/creatinina menor de 0.001, o los pacientes con hiperparatiroidismo primario con imágenes negativas, no deben ser sometidos a exploraciones quirúrgicas cervicales. En estos casos, la hipercalcemia hipocalciúrica familiar representa un diagnóstico confiable; se puede administrar Cinacalcet en casos de hipercalcemia sintomática.

Introdução. A hipercalcemia hipocalciúrica familiar é um distúrbio hereditário raro do metabolismo do cálcio, no qual uma alteração no ponto de ajuste da secreção do hormônio da paratireóide causa hipercalcemia com hipocalciúria relativa. Alguns dados sugerem que sua prevalência gira em torno de 74.1 por 100,000 habitantes. Os pacientes geralmente são assintomáticos. No entanto, eles podem desenvolver sintomas leves e um adenoma de paratireoide hiperativo, que representa seu principal diagnóstico diferencial. O objetivo foi descrever o caso de um paciente e destacar a importância da suspeita clínica e do diagnóstico para evitar exploração cirúrgica cervical desnecessária em busca de adenomas de paratireoide. Relato de caso. É o caso de um homem de 40 anos com perfil bioquímico compatível com hiperparatireoidismo primário, com imagens anatômicas e funcionais negativas para adenoma, além de relação depuração de cálcio/creatinina menor que 0.001, considerando hipercalcemia hipocalciúrica familiar. Estudos genéticos revelam uma mutação no gene receptor da sensibilidade ao cálcio e confirmam o diagnóstico. Discussão. O principal diagnóstico diferencial da hipercalcemia hipocalciúrica familiar é um adenoma de paratireoide hiperativo. Em ambos os casos, os sintomas podem estar ausentes ou leves; o cálcio sérico excede o limite superior e o hormônio da paratireóide é superior a 25pg/ml. A relação depuração de cálcio/creatinina deve ser usada para diferenciar entre essas patologias e evitar exploração cirúrgica cervical desnecessária. Além da falta de informações sobre esta questão, as evidências apoiam o uso de calcimiméticos para tratar a hipercalcemia sintomática. Conclusões. Pacientes com hipercalcemia leve, com valores de hormônio da paratireóide maiores que 25pg/ml e uma relação de depuração de cálcio/creatinina menor que 0.001, ou pacientes com hiperparatireoidismo primário com imagens negativas, não devem ser submetidos a exploração cirúrgica cervical. Nesses casos, a hipercalcemia hipocalciúrica familiar representa um diagnóstico confiável; Cinacalcet pode ser administrado em casos de hipercalcemia sintomática.

Judicialização do cinacalcete no estado do Rio de Janeiro / Judicialization of cinacalcet in Rio de Janeiro State

Objetivo: Analisar a judicialização do cinacalcete no estado do Rio de Janeiro e estimar o seu impacto no orçamento do estado do Rio de Janeiro no ano de 2015. Métodos: Estudo transversal descritivo que analisou os pareceres técnicos emitidos pelo Núcleo de Assessoria Técnica em Ações de Saúde do Tribunal de Justiça do Rio de Janeiro entre 2009 e 2016. Realizou-se uma busca no banco de licitações da Secretaria de Estado de Saúde do Rio de Janeiro para encontrar o valor pago por esse medicamento em 2015. Resultados: Entre 2009 e 2015, esse núcleo elaborou 23.852 pareceres, com 1.553 relacionados ao cinacalcete, sendo 359 em 2015. Entre os autores, 88% residiam na capital deste estado, 50,4% eram mulheres, 46% tinham renda entre 1 e 3 salários mínimos. A decisão judicial foi favorável ao autor em 100% dos processos. Conclusão: Em 2015, foram gastos cerca de 3,7 milhões de reais para compra desse medicamento, o que equivale a 2,5% dos recursos destinados à assistência farmacêutica do estado do Rio de Janeiro neste ano, caracterizando um elevado impacto no orçamento da saúde

Objective: Analyze the judicialization of cinacalcet in Rio de Janeiro and estimate its impact on the budget of Rio de Janeiro State in 2015. Methods: It is a cross sectional study that analyzed the technical reports issued by the Technical Advisory Core of the Court of Justice in Rio de Janeiro between 2009 and 2016. It was realized a search in the bids database of Health Secretary of Rio de Janeiro state to define the value spent for this drug in 2015. Results: Between 2009 and 2015, the Core Technical Advisory prepared 23,852 reports, 1,553 of them related to cinacalcet, 359 in 2015. Among the authors, 88% were living in the capital of Rio de Janeiro, 50.4% were women, 46% with income between 1 and 3 minimum wages. The court decision was favorable to the author in 100% of the processes. Conclusion: In 2015, about R$ 3.7 million were spent, which is equivalent to 2.5% of the resources destined to pharmaceutical assistance in Rio de Janeiro at that year, causing a high impact in the health's budget

Therapy for persistent hypercalcemic hyperparathyroidism post-renal transplant: cinacalcet versus parathyroidectomy / Tratamento do hiperparatireoidismo hipercalcêmico persistente pós-transplante renal: cinacalcete versus paratireoidectomia

ABSTRACT Background: Persistent hyperparathyroidism post-transplant is associated with increases in the incidence of cardiovascular events, fractures, and deaths. The aim of this study was to compare both therapeutic options available: parathyroidectomy (PTX) and the calcimimetic agent cinacalcet. Methods: A single center retrospective study including adult renal transplant recipients who developed hypercalcemia due to persistent hyperparathyroidism. Inclusion criteria: PTH > 65 pg/mL with serum calcium > 11.5 mg/dL at any time after transplant or serum calcium persistently higher than 10.2 mg/dL one year after transplant. Patients treated with cinacalcet (n=46) were compared to patients treated with parathyroidectomy (n=30). Follow-up period was one year. Clinical and laboratory data were analyzed to compare efficacy and safety of both therapeutic modalities. Results: PTX controlled calcemia faster (month 1 x month 6) and reached significantly lower levels at month 12 (9.1±1.2 vs 9.7±0.8 mg/dL, p < 0.05); PTX patients showed significantly higher levels of serum phosphate (3.8±1.0 vs 2.9±0.5 mg/dL, p < 0.05) and returned PTH to normal levels (45±51 pg/mL). Cinacalcet, despite controlling calcium and phosphate in the long term, decreased but did not correct PTH (197±97 pg/mL). The proportion of patients that remained with PTH above normal range was 95% in the cinacalcet group and 22% in the PTX group. Patients treated with cinacalcet had better renal function (creatinine 1.2±0.3 vs 1.7±0.7 mg/dL, p < 0.05). Conclusions: Surgical treatment was superior to cinacalcet to correct the metabolic disorders of hyperparathyroidism despite being associated with worse renal function in the long term. Cinacalcet proved to be a safe and well tolerated drug.

RESUMO Introdução: O hiperparatireoidismo persistente pós-transplante está associado a aumento na incidência de eventos cardiovasculares, fraturas e óbitos. O objetivo deste estudo foi comparar as opções terapêuticas disponíveis: paratireoidectomia (PTX) e o agente calcimimético cinacalcete. Métodos: Estudo retrospectivo de um único centro incluiu pacientes transplantados renais adultos que desenvolveram hipercalcemia devido a hiperparatireoidismo persistente. Critérios de inclusão: PTH > 65 pg/mL com cálcio sérico > 11,5 mg/dL a qualquer momento após o transplante, ou cálcio sérico persistentemente superior a 10,2 mg/dL um ano após o transplante. Os pacientes tratados com cinacalcete (n = 46) foram comparados aos pacientes tratados com paratireoidectomia (n = 30). O período de acompanhamento foi de um ano. Dados clínicos e laboratoriais foram analisados para comparar a eficácia e a segurança de ambas as modalidades terapêuticas. Resultados: a PTX controlou a calcemia mais rapidamente (mês 1 x mês 6) e atingiu níveis significativamente mais baixos no mês 12 (9,1 ± 1,2 v.s. 9,7 ± 0,8 mg/dL, p < 0,05); pacientes submetidos à PTX apresentaram níveis significativamente mais altos de fósforo sérico (3,8 ± 1,0 v.s. 2,9 ± 0,5 mg/dL, p < 0,05) e retornaram aos níveis normais de PTH (45 ± 51 pg/mL). O cinacalcete, apesar de controlar o cálcio e o fósforo no longo prazo, diminuiu, mas não corrigiu o PTH (197 ± 97 pg/mL). A proporção de pacientes que permaneceram com PTH acima da faixa normal foi de 95% no grupo cinacalcete e 22% no grupo PTX. Os pacientes tratados com cinacalcete apresentaram melhor função renal (creatinina 1,2 ± 0,3 v.s. 1,7 ± 0,7 mg/dL, p < 0,05). Conclusões: O tratamento cirúrgico foi superior ao cinacalcete para corrigir os distúrbios metabólicos do hiperparatireoidismo, apesar de estar associado a pior função renal no longo prazo. Cinacalcete provou ser um medicamento seguro e bem tolerado.

Un caso de hipercalcemia hipocalciúrica de causa genética en niño prepúber / Genetic hypercalcemic hypocalciuria in a prepubertal boy

Un paciente de 12 años consultó por vómitos recurrentes asociados con cefaleas, con varios episodios durante 7 meses, y retraso ponderal secundario a esa sintomatología. Había recibido previamente un tratamiento con antibióticos e inhibidores de la bomba de protones, por diagnóstico de gastritis a Helicobacter pylori, después de biopsia gástrica realizada durante una videoendoscopía digestiva alta. Se desconoce su historia familiar porque es hijo adoptivo. Al examen físico el paciente estaba adelgazado, sin tumoración a nivel de cuello; presentaba genitales prepuberales. Como el paciente continuó con vómitos cíclicos recurrentes, siguieron exámenes complementarios donde se constató en 2 oportunidades hipercalcemia (13,2-13,6 mg/dl), acompañada de hipofosfatemia (2,7 mg/dl). Con un diagnóstico presuntivo de hiperparatiroidismo primario se realizaron dosajes de laboratorio: calcemia total e iónica elevada (12,1 y 5,6mg/dl respectivamente), fosfatemia baja (2,8 mg/dl), fosfatasa alcalina sérica normal (151 mU/ml), PTH sérica normal (47,1 pg/ml), 25(OH)vitamina D sérica adecuada (22 ng/ml). La ecografía de glándulas tiroides y paratiroides mostró una imagen redondeada hipoecoica, avascular, de 4 mm axial por 4 mm cefalocaudal, por 3 mm ánteroposterior en topografía paratiroidea derecha, planteándose la posibilidad de hipertrofia paratiroidea versus adenopatía. Se realizó estudio de paratiroides por imágenes: centellograma con 99mTc-MIBI y PET-CT con 18F-colina, pero no se constató captación anormal. Se realizaron nuevos estudios de laboratorio: en orina de 24 horas el calcio era de 19 mg, el cociente calcio/creatinina urinaria 0,03 mg/mg, la reabsorción tubular de fósforo normal (82%) y el cociente de las tasas de depuración de calcio y creatinina muy bajo (0,00046). El CTX sérico era bajo. El diagnóstico clínico fue de hipercalcemia hipocalciúrica; ante la falta de antecedentes familiares, se realizó un estudio de posibles mutaciones puntuales en el gen del receptor de calcio (CaSR), hallándose la presencia en heterocigosis de la mutación p.Arg185Gln (p.R185Q) en la posición 554 (c.554G>A) del exón 4 del gene CaSR. Esto implica el cambio de una arginina por glutamina en el codón 185 de la proteína, y confirma el origen genético de la hipercalcemia hipocalciúrica en nuestro paciente. La edad ósea era de 12 años, y se indicó un tratamiento con testosterona i.m. a bajas dosis para acelerar el desarrollo puberal; luego de 4 aplicaciones mensuales su talla se ha incrementado en 4 cm y su peso en 3 kg. Una aplicación subcutánea de denosumab (60 mg) no controló la hipercalcemia. Continuó por un año con hipoorexia y un episodio de vómitos por semana, pero actualmente tiene buen apetito y excelente tolerancia digestiva. Se le ha prescripto cinacalcet oral (AU)

A 12-year-old patient who consulted for recurrent vomiting associated with headaches, with several episodes for 7 months, and low body weight. The patient had previously received treatment with antibiotics and proton pump inhibitors, due to gastritis with Helicobacter pylori, after gastric biopsy performed during videoendoscopy. His family history is unknown because he is an adopted son. At physical examination the patient was thin, without neck tumor; he had prepubertal genitalia. As he patient continued with recurrent vomiting, he was admitted for further evaluation. Laboratory studies revealed hypercalcemia (13.2-13.6 mg/dl), accompanied by hypophosphatemia (2.7 mg/dl). With a presumptive diagnosis of primary hyperparathyroidism, complementary determinations were performed: total and high total and ionized serum calcium (12.1 and 5.6 mg/dl, respectively), normal serum alkaline phosphatase (151 mU/ml), and PTH (47.1 pg/ml), and normal serum 25(OH) vitamin D (32 ng/ml). The ultrasonography of thyroid and parathyroid glands showed a rounded hypoechoic, avascular image, 4 mm in diameter in the lower right parathyroid topography. A parathyroid imaging studies were performed: scintigraphy with 99mTc-MIBI and PET-CT with 18F-choline, but no abnormal uptake was observed. New laboratory studies were carried out: in 24-hour urine the calcium was 19 mg, the urinary calcium/creatinine ratio was 0.03 mg/mg, the tubular reabsorption of phosphorus was normal (82%) and the ratio of clearances rates of calcium and creatinine very low (0.00046). Serum CTX was low. The clinical diagnosis was hypocalciuric hypercalcemia; in the absence of a family history, a study of possible point mutations in the calcium receptor gene (CaSR) was carried out; there was a heterozygous mutation: p.Arg185Gln (p.R185Q) at position 554 (c.554G)>A) of exon 4 of the CaSR gene. This involves the exchange of an arginine for glutamine at codon 185 of the protein, and confirms the genetic origin of the hypocalciuric hypercalcemia in our patient. Bone age was 12 years, and a treatment with testosterone i.m. at low doses to accelerate pubertal development was started; after 4 monthly applications height has increased by 4 cm and weight by 3 kg. Loss of appetite and a weekly episode of postprandial vomiting continued during one yeas, but now his appetite is normal and vomiting has subsided. A subcutaneous application of denosumab (60 mg) did not control hypercalcemia. He has been prescribed oral cinacalcet (AU)

The impact of cinacalcet in the mineral metabolism markers of patients on dialysis with severe secondary hyperparathyroidism / Impacto de cinacalcete em marcadores do metabolismo mineral de pacientes em diálise portadores de hiperparatireoidismo secundário grave

Abstract Introduction: Treating secondary hyperparathyroidism (SHPT), a common condition associated with death in patients with chronic kidney disease, is a challenge for nephrologists. Calcimimetics have allowed the introduction of drug therapies no longer based on phosphate binders and active vitamin D. This study aimed to assess the safety and effectiveness of cinacalcet in managing chronic dialysis patients with severe SHPT. Methods: This retrospective study included 26 patients [age: 52 ± 12 years; 55% females; time on dialysis: 54 (4-236) months] on hemodialysis (N = 18) or peritoneal dialysis (N = 8) with severe SHPT (intact parathyroid hormone (iPTH) level > 600 pg/mL) and hyperphosphatemia and/or persistent hypercalcemia treated with cinacalcet. The patients were followed for 12 months. Their serum calcium (Ca), phosphorus (P), alkaline phosphatase (ALP), and iPTH levels were measured at baseline and on days 30, 60, 90, 180, and 365. Results: Patients with hyperphosphatemia (57.7%), hypercalcemia (23%), or both (19.3%) with iPTH > 600 pg/mL were prescribed cinacalcet. At the end of the study, decreases were observed in iPTH (1348 ± 422 vs. 440 ± 210 pg/mL; p < 0.001), Ca (9.5 ± 1.0 vs. 9.1 ± 0.6 mg/dl; p = 0.004), P (6.0 ± 1.3 vs. 4.9 ± 1.1 mg/dl; p < 0.001), and ALP (202 ± 135 vs. 155 ± 109 IU/L; p = 0.006) levels. Adverse events included hypocalcemia (26%) and digestive problems (23%). At the end of the study, 73% of the patients were on active vitamin D and cinacalcet. Three (11.5%) patients on peritoneal dialysis did not respond to therapy with cinacalcet, and their iPTH levels were never below 800 pg/mL. Conclusion: Cinacalcet combined with traditional therapy proved safe and effective and helped manage the mineral metabolism of patients with severe SHPT.

Resumo Introdução: O tratamento do hiperparatireoidismo secundário (HPTs), patologia comum e associada à mortalidade na doença renal crônica, é um desafio para o nefrologista. Advento dos calcimiméticos propiciou terapêutica medicamentosa diferente da usual, baseada em quelantes de fósforo e vitamina D ativa. O objetivo deste estudo foi avaliar segurança e efetividade de cinacalcete no controle do HPTs grave de pacientes em diálise crônica. Métodos: Estudo retrospectivo 26 pacientes [idade: 52 ± 12 anos; 55% mulheres; tempo em diálise: 54 (4-236) meses], em hemodiálise (N = 18) ou diálise peritoneal (N = 8), com HPTs grave (nível de paratormônio intacto (PTHi) > 600 pg/mL), com hiperfosfatemia e/ou hipercalcemia persistentes, em tratamento com cinacalcete. Período de seguimento de 12 meses. Avaliados níveis séricos de cálcio (Ca), fósforo (P), fosfatase alcalina (FA) e PTHi no início do seguimento, 30, 60, 90, 180 e 365 dias. Resultados: Indicações para início do cinacalcete: hiperfosfatemia (57,7%), hipercalcemia (23%), ou ambos (19,3%) com PTH > 600 pg/mL. Ao final do seguimento, observada redução dos níveis PTHi (1348 ± 422 vs. 440 ± 210 pg/mL; p < 0,001), Ca (9,5 ± 1,0 vs. 9,1 ± 0,6 mg/dl; p = 0,004), P (6,0 ± 1,3 vs. 4,9 ± 1,1 mg/dl; p < 0,001) e FA (202 ± 135 vs. 155 ± 109 UI/L; p = 0,006). Eventos adversos: hipocalcemia (26%) e queixas digestivas (23%). No fim do estudo, 73% pacientes utilizavam vitamina D ativada associada ao cinacalcete. Três (11,5%) pacientes, todos em DP, não responderam ao cinacalcete, mantendo níveis PTHi > 800 pg/mL. Conclusão: Utilização de cinacalcete, associado à terapia tradicional, em pacientes com HPTs grave foi segura, eficiente e associada a melhor controle do metabolismo mineral.