A review of drug-induced hypocalcemia

Does the use of bisphosphonates during pregnancy affect fetal outcomes? A systematic review

PURPOSE

This systematic review aimed to determine the effects of maternal exposure to bisphosphonates (BPs) during pregnancy on neonatal outcomes. It aimed to disclosfe the impact of BPs on neonates and identify aspects that require further investigation.

METHODS

A comprehensive search of PubMed, Science Direct, LILACS, EMBASE, and Web of Science was conducted until August 2022, with no time restrictions. The selection criteria included studies published in English that evaluated pregnant women who were exposed to BPs.

RESULTS

From an initial pool of 2169 studies, 13 met the inclusion criteria for this systematic review. These studies collectively included 106 women (108 pregnancies) who were exposed to BPs either before orduring pregnancy. A summary of the key characteristics of the selected studies and the risk of bias assessment are provided. Exposure to BPs occurs at various stages of pregnancy, with different indications for BP treatment. The most frequently reported neonatal outcomes were spontaneous abortion, congenital malformations, hypocalcemia, preterm birth, and low birth weight.

CONCLUSION

Although previous reports have linked BPs before or during pregnancy with adverse neonatal outcomes, these associations should be interpreted with caution. Given the complexity of these findings, further research is necessary to provide more definitive insights to guide clinical decisions regarding the use of BPs in pregnant women.

Renal calcium and magnesium handling during pregnancy: modeling and analysis

Pregnancy is associated with elevated demand of most nutrients, with many trace elements and minerals critical for the development of fetus. In particular, calcium (Ca2+) and magnesium (Mg2+) are essential for cellular function, and their deficiency can lead to impaired fetal growth. A key contributor to the homeostasis of these ions is the kidney, which in a pregnant rat undergoes major changes in morphology, hemodynamics, and molecular structure. The goal of this study is to unravel the functional implications of these pregnancy-induced changes in renal handling of Ca2+ and Mg2+, two cations that are essential in a healthy pregnancy. To achieve that goal, we developed computational models of electrolyte and water transport along the nephrons of a rat in mid and late pregnancy. Model simulations reveal a substantial increase in the reabsorption of Mg2+ along the proximal tubules and thick ascending limbs. In contrast, the reabsorption of Ca2+ is increased in the proximal tubules but decreased in the thick ascending limbs, due to the lower transepithelial concentration gradient of Ca2+ along the latter. Despite the enhanced transport capacity, the marked increase in glomerular filtration rate results in elevated urinary excretions of Ca2+ and Mg2+ in pregnancy. Furthermore, we conducted simulations of hypocalcemia and hypomagnesemia. We found that hypocalcemia lowers Ca2+ excretion substantially more than Mg2+ excretion, with this effect being more pronounced in virgin rats than in pregnant ones. Conversely, hypomagnesemia reduces the excretion of Mg2+ and Ca2+ to more similar degrees. These differences can be explained by the greater sensitivity of the calcium-sensing receptor (CaSR) to Ca2+ compared with Mg2+.NEW & NOTEWORTHY A growing fetus' demands of minerals, notably calcium and magnesium, necessitate adaptations in pregnancy. In particular, the kidney undergoes major changes in morphology, hemodynamics, and molecular structure. This computational modeling study provides insights into how these pregnancy-induced renal adaptation impact calcium and magnesium transport along different nephron segments. Model simulations indicate that, despite the enhanced transport capacity, the marked increase in glomerular filtration rate results in elevated urinary excretions of calcium and magnesium in pregnancy.

Assessment of Vitamin D Status in Primary Hyperparathyroidism Patients: A Retrospective Study

BACKGROUND

Primary hyperparathyroidism (PHPT), a condition that manifests in various clinical forms, is a significant health concern. Normocalcemic primary hyperparathyroidism (NPHPT) is characterized by normal calcemia despite elevated parathyroid hormone (PTH) levels. Vitamin D deficiency can contribute to the clinical spectrum and complexity of NPHPT. Low vitamin D levels can elevate PTH, making it difficult to distinguish between NPHPT and secondary hyperparathyroidism. Additionally, it might mask hypercalcemia, leading to an underestimation of the disease severity. Our study aims to shed light on these complexities by investigating normocalcemic and hypercalcemic PHPT patient's clinical, hormonal, and biochemical patterns, including their vitamin D status.    Materials: In this retrospective study, we enrolled 60 PHPT patients with autonomous parathyroid function confirmed using a combination of ultrasonography, radionuclide scan, and parathyroid function index calculation. We evaluated the albumin-corrected calcemia, calciuria, PTH, 25(OH)D level, serum phosphate, bone mineral density, and major clinical symptoms (fracture, nephrolithiasis). A comparative analysis and a correlation study were performed between normo- and hypercalcemic and vitamin D-deficient and vitamin D-non-deficient groups.

RESULTS

 The median age was 62 years, 51.66% (31/60) being normocalcemic and 46.66% (29/60) presenting a deficient 25(OH)D level. In the group with 25(OH)D below 20 ng/mL, we observed a reduced level of albumin-corrected calcemia, without a significant increase of PTH compared to the adequate 25(OH)D level group. The frequency of the NPHPT and the risk of fracture were significantly higher in the deficient 25(OH)D group (20/60, 33.33% and 8/60, 13.33%) than in the adequate one (11/60, 18.33% and 1/60, 1.66%) with OR=4.7 (p<0.004) and OR=9.7 (p<0.027), respectively. We also found a positive correlation between PTH and adenoma size, the parathyroid function index and adenoma size, as well as PTH and phosphate levels. However, the correlation between 25(OH)D and phosphate levels was negative and moderate (rho=-0.504, p<0.001), adding a new layer of complexity to our understanding of these relationships.

CONCLUSION

Our study provided significant insight into the link between vitamin D status and normocalcemic PHPT. We found that vitamin D-deficient patients with normocalcemic PHPT have an increased fracture risk, which requires meticulous monitoring and possible supplementation with vitamin D. This should be done carefully to avoid exacerbating hypercalcemia or hypercalciuria. Further research is needed to refine these management strategies and deepen our understanding of the complex relationships between the analyzed parameters.

Diagnosis and treatment of Paget's disease of bone: position paper from the Italian Society of Osteoporosis, Mineral Metabolism and Skeletal Diseases (SIOMMMS)

INTRODUCTION

Paget's disease of bone is a focal skeletal disorder causing bone deformities and impairing bone quality. Despite the prevalence of asymptomatic cases is increasing, the progression of the disease can lead to invalidating complications that compromise the quality of life. Doubts on clinical and therapeutic management aspects exist, although beneficial effects of antiresorptive drugs, particularly bisphosphonates are known. However, limited information is available from randomized controlled trials on the prevention of disease complications so that somewhat contrasting positions about treatment indications between expert panels from the main scientific societies of metabolic bone diseases exist. This task force, composed by expert representatives appointed by the Italian Society of Osteoporosis, Mineral Metabolism and Skeletal Diseases and members of the Italian Association of Paget's disease of bone, felt the necessity for more specific and up to date indications for an early diagnosis and clinical management.

METHODS

Through selected key questions, we propose evidence-based recommendations for the diagnosis and treatment of the disease. In the lack of good evidence to support clear recommendations, available information from the literature together with expert opinion of the panel was used to provide suggestions for the clinical practice.

RESULTS AND CONCLUSION

Description of the evidence quality and support of the strength of the statements was provided on each of the selected key questions. The diagnosis of PDB should be mainly based on symptoms and the typical biochemical and radiological features. While treatment is mandatory to all the symptomatic cases at diagnosis, less evidence is available on treatment indications in asymptomatic as well as in previously treated patients in the presence of biochemical recurrence. However, given the safety and long-term efficacy of potent intravenous bisphosphonates such as zoledronate, a suggestion to treat most if not all cases at the time of diagnosis was released.

Predictive factors for severe outcomes in substance abuse-related emergency visits: A 5-year retrospective analysis at a medical center in Taiwan

BACKGROUND

Substance abuse is a considerable medical issue worldwide, yet current surveillance systems in Taiwan offer limited insights into the clinical characteristics and outcomes of substance abuse patients. This study aimed to delineate the epidemiology of emergency department visits related to substance abuse at a hospital in Taiwan and to identify factors predictive of severe complications or mortality.

METHODS

A retrospective analysis was conducted on substance abuse-related emergency department visits at a medical center in Taiwan between 2009 and 2013. Eligible participants were individuals aged 20 or older who had confirmed substance abuse through urinalysis. Variables such as patient demographics, substances abused, clinical characteristics, and outcomes were collected. Severe outcomes were defined as admission to the intensive care unit, requirement for endotracheal intubation, or in-hospital death. Logistic regression models were employed to identify factors contributing to severe outcomes.

RESULTS

The cohort consisted of 623 patients, of whom 64.0% were female and 67.1% were aged between 20 and 49 years. Benzodiazepines were detected in 75.3% of patients, while z-drugs (specifically zopiclone, zolpidem, or zaleplon) were found in 27.8%. Depressants, stimulants, and hallucinogens were present in 14.9%, 10.6%, and 0.6% of the cases, respectively. Of the patient, 121 (19.4%) experienced severe outcomes, including 116 (18.6%) intensive care unit admissions, 73 (11.7%) intubations, and 11 (1.8%) in-hospital deaths. Multivariable logistic regression analysis revealed multiple predictors of severe outcomes, such as emergency department triage level, aspiration pneumonia, leukocytosis, abnormal hepatic function, abnormal renal function, hypernatremia, and hypocalcemia.

CONCLUSION

In Taiwan, benzodiazepines emerged as the most prevalent substance of abuse among emergency department visitors, and a significant proportion of these patients experienced severe outcomes. Continuous monitoring of severe outcome predictors is essential for enhanced understanding and management.

[Exercise therapy and basic treatment for osteoporosis]

Physical training is an important component in the prophylaxis of osteoporosis and the prevention of fractures. Physical training not only has a direct effect on muscle strength and muscular performance, but also on the risk of falling and the fear of falling. Therefore, physical training is also an integral part of the basic treatment for osteoporosis. The recommendations for basic treatment are an adequate intake of nutrients, including protein in particular. The intake of calcium and vitamin D in sufficient quantities is also important and, in the case of specific drug therapy, also to avoid side effects and to ensure the therapeutic effect. This article summarizes the recommendations of the updated S3 guideline on the diagnosis and treatment of osteoporosis and explains the background for the recommendations included.

Micronutrients and Nutrition Status of School-Aged Children in Indonesia

Micronutrient deficiencies (MNDs) in school-aged children are still a major health problem in Indonesia. This study was designed to examine the status of micronutrients and their relationship to the nutritional status of children aged 5-12 years since an up-to-date database on the micronutrient status of children aged 5-12 years is needed. Data from the 2018 Indonesian Basic Health Research (Riskesdas) were used in this study, with 2456 subjects for analysis. Micronutrient analysis was carried out, including iron status (ferritin, C reactive protein (CRP)), levels of zinc, vitamin D, calcium, and vitamin A (retinol) in school-aged children (5-12 years). The ELISA measurement was applied to measure CRP, ferritin, and vitamin D. Zinc levels were analysed with atomic absorbance spectroscopy (AAS). Moreover, high-performance liquid chromatography (HPLC) was applied to calculate vitamin A. In addition, stunting and thinness data were also obtained from the Riskesdas study. The results showed that the prevalence of stunting and thinness in school-aged children was 11.4% and 9.2%, respectively, showing that the stunting prevalence in the city was lower than in the village (4.5% vs. 6.9%, P = 0.000, respectively). In addition, the prevalence of MNDs in Indonesian children was 13.4%, 19.7%, 4.2%, 3%, and 12.7% for ferritin, zinc, calcium, vitamin A, and vitamin D, respectively. The mean serum level of vitamin A and zinc was significantly lower in stunted children compared to normal school children (P = 0.010 and P = 0.014). The serum concentration of vitamin D was significantly lower in overweight children compared to thin and normal children (P = 0.000). Serum values of ferritin, zinc, and vitamin A were significantly higher in overweight children compared to thin and normal children (P = 0.000). A poor correlation was observed between the z-score of height-for-age (HAZ) and the levels of zinc (r = 0.089, P = 0.000), vitamin A (r = 0.105, P = 0.000), and vitamin D (-0.073, P = 0.000). In addition, very weak correlations between z-scores of body mass index-for-age (BAZ) and the serum concentrations of ferritin (0.091, P = 0.000), zinc (r = 0.115, P = 0.000), vitamin A (r = 0.137, P = 0.000), and vitamin D (r = -0.112, P = 0.000) were also seen. In conclusion, school-aged children in Indonesia experienced stunting, thinness, and micronutrient deficiency. Furthermore, stunting and thinness were also related to micronutrient deficiencies.

Using sequential pharmacotherapy for the treatment of osteoporosis: an update of the literature

INTRODUCTION

Osteoporosis, which is characterized by compromised bone density and heightened susceptibility to fractures, is a substantial public health concern, especially among the aging population. Underdiagnosis, undertreatment, and therapy non-adherence contribute to its impact. Anabolic and dual-action agents like teriparatide, abaloparatide, and romosozumab have emerged as effective treatments, allowing rapid gains in bone mineral density (BMD) and reducing fracture risk. However, administering treatments in the correct order is paramount, with an 'anabolic first' approach gaining traction for patients at high risk of fractures. This strategy involves starting anabolic therapies, followed by antiresorptive agents as maintenance therapy. It is important to note that the effectiveness of anabolic agents differs between treatment-naive and previously treated patients: tailored treatment approaches are therefore necessary. This comprehensive strategy adheres to clinical guidelines, emphasizing individualized care, early intervention, and patient-centered management to mitigate the burden of osteoporosis and enhance patients' quality of life.

AREA COVERED

The aim of this review is to summarize recent evidence on the sequential treatment of osteoporosis and to provide recommendations on the best treatment strategies.

EXPERT OPINION

Effective treatments, such as anabolic agents, are key in high-risk patients, who require an 'anabolic first' approach. Sequential therapy, specifically tailored to a patient's history, can help to optimize prevention and management of fractures.

Drug treatment strategies for Paget's disease: relieving pain and preventing progression

INTRODUCTION

Paget's disease of bone (PDB) is a focal bone disorder caused by a marked dysregulation of osteoblasts and osteoclasts in basic multicellular units, leading to abnormal and disorganized deposition of collagen fibers (the so-called "woven bone"). Therefore, pagetic bones are increased in size, and at increased risk for bone pain, deformities, fractures, osteoarthritis, and, more rarely, neoplastic degeneration.

AREAS COVERED

In this review we revise the available information concerning the pharmacological treatment of PDB.

EXPERT OPINION

PDB progresses slowly within the affected skeletal sites and, if untreated, often leads to bone overgrowth, with bone pain, deformity and a likely increased risk of complications. Thus, the primary goal of treatment is the restoration of a normal bone turnover, in order to relieve bone pain or other symptoms and possibly prevent the complications. PDB long remained a poorly treatable disorder until the discovery of antiresorptive agents such as calcitonin first and bisphosphonates (BPs) later. With the recent development of potent intravenous BPs like zoledronate, allowing a better control of disease activity over the long term with a single infusion, has contributed to a marked improvement of the clinical management of this invalidating disorder.

Loss of Seizure Control in a Patient With Vitamin D Deficiency and Phenytoin-Induced Hypocalcemia

Phenytoin is a widely used antiseizure drug with well-documented side effects, including hypocalcemia, particularly in patients with concomitant vitamin D deficiency. Decreased serum calcium levels can induce seizures. In stabilized patients under long-term anticonvulsant treatment with phenytoin, loss of seizure control is rare but has been reported. This report illustrates a case of a 69-year-old woman under treatment with phenytoin for more than 10 years, who presented persistent hypocalcemia despite calcium correction, and seizures refractory to treatment with four combined antiepileptic drugs. She also presented with low vitamin D and elevated parathyroid hormone levels. Only when phenytoin administration was stopped it was possible to correct hypocalcemia and achieve seizure control. This case illustrates the need for regular monitoring and supplementation with calcium and vitamin D for patients under prolonged treatment with phenytoin. The proposed mechanism for phenytoin-induced hypocalcemia is reviewed. When installed, hypocalcemia can be resistant to supplementation until phenytoin is stopped, and in rare cases may lead to loss of seizure control.

Prothrombotic state and calcium deficiency in early pregnancy are risk factors for gestational diabetes mellitus: a retrospective cohort study

OBJECTIVES

To investigate whether the prothrombotic state (PTS), calcium deficiency and iron deficiency anemia (IDA) in early pregnancy is associated with the risk of gestational diabetes mellitus (GDM).

METHODS

We conducted a retrospective cohort study, including consecutive pregnant women tested for PTS, calcium deficiency and IDA before 20 weeks' gestation between September 1, 2017 and March 21, 2021. For routine prenatal care, pregnant women underwent a 75-g oral glucose tolerance test (OGTT) to make a GDM diagnosis during 24-28 weeks of gestation. Testing data and relevant clinical information were obtained from Shenzhen Baoan Women's and Children's Hospital. To estimate GDM risk of exposures (PTS, calcium deficiency and IDA) in early pregnancy, we used logistic regression to obtain odds ratio (OR) adjusted for maternal age, parity, family history of diabetes and pre-pregnancy body mass index.

RESULTS

The cohort included 8396 pregnant women with complete data of exposures and GDM outcomes. Baseline characteristics were not comparable between exposure and control groups. PTS (adjusted OR 2.38, 95% CI 1.61-3.52) or calcium deficiency (adjusted OR 1.23, 95% CI 1.02-1.49) in early pregnancy was independently associated with increased GDM risk after adjusting covariates. There was no significant association between IDA status and GDM risk (adjusted OR 0.86, 95% CI 0.63-1.18).

CONCLUSIONS

PTS and calcium deficiency in early pregnancy may be independent risk factors of GDM. These findings need further validation in well-designed prospective cohorts.

Interactions between Food and Drugs, and Nutritional Status in Renal Patients: A Narrative Review

Drugs and food interact mutually: drugs may affect the nutritional status of the body, acting on senses, appetite, resting energy expenditure, and food intake; conversely, food or one of its components may affect bioavailability and half-life, circulating plasma concentrations of drugs resulting in an increased risk of toxicity and its adverse effects, or therapeutic failure. Therefore, the knowledge of these possible interactions is fundamental for the implementation of a nutritional treatment in the presence of a pharmacological therapy. This is the case of chronic kidney disease (CKD), for which the medication burden could be a problem, and nutritional therapy plays an important role in the patient’s treatment. The aim of this paper was to review the interactions that take place between drugs and foods that can potentially be used in renal patients, and the changes in nutritional status induced by drugs. A proper definition of the amount of food/nutrient intake, an adequate definition of the timing of meal consumption, and a proper adjustment of the drug dosing schedule may avoid these interactions, safeguarding the quality of life of the patients and guaranteeing the effectiveness of drug therapy. Hence, a close collaboration between the nephrologist, the renal dietitian, and the patient is crucial. Dietitians should consider that food may interact with drugs and that drugs may affect nutritional status, in order to provide the patient with proper dietary suggestions, and to allow the maximum effectiveness and safety of drug therapy, while preserving/correcting the nutritional status.

Iatrogenic Toxicities in the Intensive Care Unit

Drug-induced iatrogenic toxicities are common in critically ill patients and have been associated with increased morbidity and mortality. Early recognition and management of iatrogenic toxicities is essential; however, the diagnosis is usually complicated by the underlying critical illness, comorbidities, and administration of multiple medications. This article reviews several types of iatrogenic toxicities associated with medications that are commonly used in critically ill patients. The mechanism of the iatrogenic toxicities, clinical presentation, and diagnosis, as well as management are discussed.

High concentrations of calcium suppress osteogenic differentiation of human periodontal ligament stem cells in vitro

Background/purpose

Periodontal ligament stem cells (PDLSCs)-based regeneration therapy has received attention for its potential alternative applications in hard tissue and tooth. However, the environmental diversity of oral cavity that regulates PDLSCs differentiation has made it difficult to develop. Therefore, we investigated how high calcium concentrations in the oral environment influence osteogenic differentiation of human PDLSCs (hPDLSCs).

Materials and methods

hPDLSCs collected from human molars were isolated and cultured with CaCl₂. First, multi lineage differentiation potentials to osteogenic, chondrogenic, and adipogenic cells were investigated. Then, the effects of CaCl₂ on both alkaline phosphatase (ALP) activity and bone mineralization were analyzed and the expression of mRNA and protein for osteogenic marker was explored. Further, luciferase assay was performed to evaluate CaCl₂ could regulate the transcriptional activity on osteogenic differentiation in hPDLSCs

Results

CaCl₂ treatment at normal to high concentrations showed similar suppression of ALP activity, while mineralized nodule formation was decreased by CaCl₂ treatment dose-dependently without affecting proliferation or cytotoxicity in hPDLSCs. We also observed that CaCl₂ treatment repressed the mRNA expression and protein abundance of osteogenic genes and transcriptional factors. Notably, repression of the Runx2 level was significant, and CaCl₂ treatment inhibited Runx2-mediated transcriptional activity on the osteoblast-specific element (OSE) and ALP promoters.

Conclusion

High concentrations of calcium negatively regulate osteogenic differentiation of hPDLSCs, by repressing osteogenic gene expressions and transcriptional activity. Therefore, these conditions may be applicable to determine the physiologically appropriate concentration of calcium.

Acute effect of hydrocortisone for respiratory deterioration in preterm infants: Oxygenation, ventilation, vital signs, and electrolytes

BACKGROUND

Preterm infants with severe bronchopulmonary dysplasia require rescue therapy with glucocorticoids, and hydrocortisone is increasingly replacing dexamethasone. The standard for rescue therapy is unclear.

AIM

To quantify the short-term effects of respiratory rescue hydrocortisone of 4 mg/kg/day for 3 days.

STUDY DESIGN

Retrospective single-center study.

SUBJECTS

Ventilator-dependent infants born at <28 weeks of gestation with an increased oxygen demand to maintain the target oxygen saturation at 88% to 95% >1 week after birth.

OUTCOME MEASURES

Ventilator settings, SpO₂/FiO₂ ratio, heart rate, and blood parameters within 24 h before and 228 h after starting hydrocortisone.

RESULTS

Twenty-five infants (median gestational age, 25.1 weeks) received hydrocortisone at a median age of 16 days. The median pre-therapy SpO₂/FiO₂ was 297 (interquartile range, 265-320) and began to rise after 12 h of administration, reaching 307 (interquartile range, 278-335). The increase in SpO₂/FiO₂ peaked from the third day to 3 days after therapy (median range, 341-356). SpO₂/FiO₂ decreased thereafter and remained unchanged from 6 and 7 days after therapy (median range, 304-314). The pCO₂ level (median range, 49-53 mmHg) did not change significantly. The heart rate significantly decreased from -4 to -6 beats/min from the first day to 1 day after therapy. Systolic blood pressure increased by a median of 4 to 8 mmHg after therapy. Blood electrolytes and glucose were similar after therapy.

CONCLUSION

Rescue hydrocortisone administration improved oxygenation without particular adverse effects at the stage of respiratory deterioration in preterm infants.

Predictors for development of denosumab-induced hypocalcaemia in cancer patients with bone metastases determined by ordered logistic regression analysis

This retrospective study was undertaken to identify predictors for the development of hypocalcaemia even with prophylactic administration of calcium and vitamin D, and to help guide future strategies to improve the safety, efficacy, and QOL of patients receiving denosumab. Between January 2016 and February 2020, a total of 327 advanced cancer patients at our hospital who were receiving denosumab were enrolled. Variables associated with the development of hypocalcaemia were extracted from the clinical records. The level of hypocalcaemia was evaluated using CTCAE version 5. Multivariate ordered logistic regression analysis was performed to identify predictors for the development of hypocalcaemia. Optimal cut off thresholds were determined using ROC analysis. Values of P < 0.05 (2-tailed) were considered significant. 54 patients have developed hypocalcemia (≥ Grade 1). Significant factors identified included concomitant use of vonoprazan [odds ratio (OR) = 3.74, 95% confidence interval (CI) 1.14–12.26; P = 0.030], dexamethasone (OR = 2.45, 95%CI 1.14–5.42; P = 0.022), pre-treatment levels of serum calcium (OR = 0.27, 95%CI 0.13–0.54; P < 0.001), ALP/100 (OR = 1.04, 95%CI 1.01–1.07; P = 0.003), and haemoglobin (OR = 0.79, 95%CI 0.68–0.93; P = 0.004). ROC curve analysis revealed that the threshold for pre-treatment levels of serum calcium was ≤ 9.3 mg/dL, ALP was ≥ 457 U/L, and haemoglobin was ≤ 10.4 g/dL. In conclusion, concomitant use of vonoprazan or dexamethasone, and pre-treatment levels of serum calcium (low), ALP (high) and haemoglobin (low) were identified as significant predictors for the development of denosumab-induced hypocalcaemia.

A Simple-to-Use Score for Identifying Individuals at High Risk of Denosumab-Associated Hypocalcemia in Postmenopausal Osteoporosis: A Real-World Cohort Study

Since denosumab-associated hypocalcemia occurs infrequently, data on its incidence and risk factors are limited. We aimed to evaluate risk factors and develop a useful score for identifying individuals at risk of denosumab-associated hypocalcemia. In this retrospective cohort, 790 consecutive female patients who received 60 mg denosumab at least once between 2016 and 2017 were analyzed. Based on biochemical records from a large-scale single-center, mild and moderate hypocalcemia were defined as albumin-corrected calcium (cCa) levels < 8.5 and < 8.0 mg/dL (< 2.12 and < 2.0 mmol/L), respectively. Mild and moderate hypocalcemia were observed in 8.2% and 1.0% patients, respectively. Patients who developed mild hypocalcemia had lower baseline cCa (8.9 vs. 9.3 mg/dL and 2.22 vs. 2.32mmo/L) and estimated glomerular filtration rate (75.0 vs. 83.2 mL/min/1.73 m²) and more frequent loop diuretic use (10.8% vs. 4.4%; all p < 0.05). In multivariate analysis, low baseline cCa (OR 1.29; 95% CI 1.20-1.40) and chronic kidney disease (CKD) stages 3b-5 were associated with elevated mild hypocalcemia risk (OR 2.92; 95% CI 1.38-6.20). Loop diuretics use was associated with mild hypocalcemia (OR 2.61; 95% CI 1.11-6.18) by univariate analysis, independent of baseline cCa and CKD stage. A scoring approach identified two risk groups: (1) patients without CKD (eGFR ≥ 45) and cCa < 8.5 mg/dL (2.12 mmol/L) and (2) patients with CKD (eGFR < 45) and cCa < 9.5 mg/dL (2.37 mmol/L).

Hypocalcemic Seizure Due to Vitamin D Deficiency

Aim

To emphasize the importance of vitamin D supplementation.

Background

The incidence of vitamin D deficiency has been increasing worldwide, probably due to decreased exposure to sunlight and unbalanced diet. Severe hypocalcemia following vitamin D deficiency is rather uncommon, and this leading to seizures in adults is a rare scenario.

Case description

This is the case of a 70-year-old female, a known case of coronary artery disease, who presented with one episode of seizure. Computed tomography of her brain revealed diffuse age-related atrophic changes, and electroencephalogram showed diffuse cerebral dysfunction. She was found to have severe hypocalcemia with secondary hyperparathyroidism due to vitamin D deficiency. Vitamin D bolus was given along with calcium correction, following which she improved.

Conclusion

There are a few reports of hypocalcemic seizures among children; however, the incidence is rare among adults. Calcium and vitamin D supplementation forms the mainstay of treatment.

Clinical significance

Hypocalcemic seizure is uncommon, especially among adults. Vitamin D deficiency resulting in hypocalcemic seizure, to the best of our knowledge, is an unreported scenario. This case highlights the importance of vitamin D supplementation in those with reduced sunlight exposure.

How to cite this article

Manappallil RG, Krishnan R, Veetil PP, Nambiar H, Karadan U, Anil R, et al. Hypocalcemic Seizure Due to Vitamin D Deficiency. Indian J Crit Care Med 2020;24(9):882-884.

Celiac disease and bone health: is there a gap in the management of postmenopausal osteoporosis?

Malabsorption due to celiac disease (CD) may contribute to postmenopausal osteoporosis. This study aimed to survey participants with CD regarding their bone density, fractures, and bone-preserving medications; to compare tolerance of bone-preserving medications in participants with and without CD; and to review the evidence for CD screening and osteoporosis therapies in the setting of CD. We recruited 131 participants with CD and 102 participants without CD. Of those with CD, 87% were diagnosed in adulthood and 40% had no recognized gastrointestinal symptoms. In 21% CD was diagnosed after the diagnosis of osteoporosis and in 9% after a fracture. No difference was found in the tolerability of bone medications between participants with CD and those without. Review of the literature found that, although monitoring of bone health is recommended for patients with CD, screening for CD is not generally accepted for patients with osteoporosis, although studies of the prevalence of CD in osteoporosis had incomplete ascertainment methods. There is a lack of well-conducted studies and therefore insufficient data for the efficacy and tolerability of bone medication in CD. In conclusion, both CD and menopause lead to bone loss. Identifying CD in postmenopausal women should lead to modification of osteoporosis management.

Electrolyte Disorders Induced by Antineoplastic Drugs

The use of antineoplastic drugs has a central role in treatment of patients affected by cancer but is often associated with numerous electrolyte derangements which, in many cases, could represent life-threatening conditions. In fact, while several anti-cancer agents can interfere with kidney function leading to acute kidney injury, proteinuria, and hypertension, in many cases alterations of electrolyte tubular handling and water balance occur. This review summarizes the mechanisms underlying the disturbances of sodium, potassium, magnesium, calcium, and phosphate metabolism during anti-cancer treatment. Platinum compounds are associated with sodium, potassium, and magnesium derangements while alkylating agents and Vinca alkaloids with hyponatremia due to syndrome of inappropriate antidiuretic hormone secretion (SIADH). Novel anti-neoplastic agents, such as targeted therapies (monoclonal antibodies, tyrosine kinase inhibitors, immunomodulators, mammalian target of rapamycin), can induce SIADH-related hyponatremia and, less frequently, urinary sodium loss. The blockade of epidermal growth factor receptor (EGFR) by anti-EGFR antibodies can result in clinically significant magnesium and potassium losses. Finally, the tumor lysis syndrome is associated with hyperphosphatemia, hypocalcemia and hyperkalemia, all of which represent serious complications of chemotherapy. Thus, clinicians should be aware of these side effects of antineoplastic drugs, in order to set out preventive measures and start appropriate treatments.

Hypocalcemia in cancer patients: An exploratory study

Introduction

Calcium has several physiological functions and when it registers abnormal serum levels those functions may be impacted with potentially severe consequences. There is much research on hypercalcemia in cancer patients, but there are no recent studies on the prevalence of hypocalcemia in those patients. However, there has been an evolution in oncology, namely, new drugs that may directly or indirectly result in hypocalcemia. The primary aim was to explore the association of hypocalcemia with the diverse types of cancer. The secondary aim was to study the influence that hypocalcemia might have on survival.

Methods

Review of the records of patients ≥18 years old, with total calcium <2.0 mmol/L measured in 2013 in a cancer center.

Results

Eight hundred twenty-nine patients were included. Four hundred thirty-nine (53%) were male. The median age was 63 years. The most frequent cancer diagnoses were hematological 196 (24%) and colorectal 111 (13%). Six hundred thirty-eight patients had measured serum albumin, with a median of 25.5 g/L (14-47). When corrected for albumin level, calcium was in the normal range in 210 (33%) cases. The median survival of patients with corrected calcium lower than normal was 479 days (95% confidence interval [CI]: 309-649) and that of patients with normal corrected calcium was 62 days (95% CI: 33-91), P < .001. In a multivariate analysis, age, primary cancer, and albumin were significantly associated with survival.

Conclusion

Hypocalcemia is associated with several types of cancer. A low calcium level is not by itself a factor of a poor prognosis since other factors seem to be more important.

Paradoxical deterioration in seizure control due to anticonvulsant-induced hypocalcaemia

Hepatic cytochrome P450 enzyme induction is associated with certain antiepileptic drugs (AEDs) and may result in hypocalcaemia secondary to vitamin D deficiency. We report a case of a 44-year-old man with a history of epilepsy, who presented with breakthrough seizures after having previously been seizure-free for 11 years. Investigations revealed severe hypocalcaemia with a corrected calcium of 1.7 mmol/L. His phenytoin dose was increased, and he was started on calcium supplementation. He was discharged with a corrected calcium level of 2.05 mmol/L but was readmitted 1 week later with further seizures and a corrected calcium of 1.89 mmol/L. 25-hydroxyvitamin D was low. AED-induced hypocalcaemia was suspected, which had been made paradoxically worse by the increase in phenytoin dose. Alfacalcidol was prescribed and he was switched from phenytoin to levetiracetam with resolution of hypocalcaemia and no further seizures. The authors recommend screening for calcium and vitamin D deficiency in patients on enzyme-inducing AEDs.

Effect of fatty acids from ethanol extract of Moringa oleifera seeds on kidney function impairment and oxidative stress induced by gentamicin in rats

Gentamicin, an aminoglycoside drug, used for the treatment of Gram-negative bacterial infections. Despite its potency against bacterial infections, its clinical use is limited owing to nephrotoxicity effect. However, the study investigated the nephroprotective effect of fatty acids from ethanolic extract of Moringa oleifera seeds (EEMOS) against gentamicin-induced kidney injury in rats. Forty-five male Wistar rats, 100-160 g, were divided into 5 groups as follows: Group 1 (control), 5 rats, received 0.2 ml/100 g/day of propylene glycol orally for 28 days. Group 2, 10 rats, received 100 mg/kg/day (i.p) of gentamicin (GENT) for 8 days. Group 3-5, 10 rats each, treated with EEMOS orally for 28 days at graded doses of 100, 200 and 400 mg/kg respectively after GENT treatment. Twenty four after treatment, five rats from each group were sacrificed. The remaining 5 rats were sacrificed after 2 weeks recovery period from the drugs. The result showed that GENT elicited polyuria, elevated plasma creatinine, urea, and lower plasma electrolytes and creatinine clearance levels. Measurements of 24 h urinary output demonstrated marked decrease in creatinine and potassium levels in the GENT-treated group, whereas sodium level remain unchanged. Also, GENT caused significant decrease in superoxide dismutase and an increase in malondialdehyde levels in the kidney of the rats. Histopathological examination revealed evidence of necrosis of the kidney. Treatment with EEMOS significantly ameliorated the alterations caused by GENT in the plasma, urine and kidney homogenate of the rats. Hence, the mono- and poly-unsaturated fatty acids present in EEMOS were responsible for its renoprotective ability.

Long QT and death in hospitalized patients with acute exacerbation of chronic obstructive pulmonary disease is not related to electrolyte disorders

Objectives: COPD is the fourth-leading cause of mortality worldwide. Prolonged QTc has been found to be a long-term negative prognostic factor in ambulatory COPD patients. The aim of this study was to evaluate the extent of prolonged-QTc syndrome in COPD patients upon admission to an internal medicine department, its relationship to hypomagnesemia, hypokalemia, and hypocalcemia, and the effect of COPD treatment on mortality during hospital stay.

Methods: This prospective cohort study evaluated COPD patients hospitalized in an internal medicine department. The study evaluated QTc, electrolyte levels, and known risk factors during hospitalization of COPD patients.

Results: A total of 67 patients were recruited. The median QTc interval was 0.441 seconds and 0.434 seconds on days 0 and 3, respectively. Prolonged QTc was noted in 35.8% of patients on admission and 37.3% on day 3 of hospitalization. The median QTc in the prolonged-QTc group on admission was 0.471 seconds and in the normal-QTc group 0.430 seconds. There was no significant difference in age, sex, electrolyte levels, renal function tests, or blood gases on admission between the two groups. Mortality during the hospital stay was significantly higher in the prolonged-QTc group (3 deaths, 12%) than in the normal QTc group (no deaths) (P=0.04). A subanalysis was performed, removing known causes for prolonged QTc. We found no differences in age, electrolytes, or renal functions. There was a small but significant difference in bicarbonate levels.

Conclusion: Our findings demonstrated that there was no correlation between QTc prolongation in hospitalized COPD patients and electrolyte levels, comorbidities, or relevant medications. A higher rate of mortality was noted in patients with prolonged QTc in comparison to normal QTc. As such, it is suggested that prolonged QTc could serve as a negative prognostic factor for mortality during hospitalization in COPD patients.

Correlation between hypocalcemia and acute exacerbation of chronic obstructive pulmonary disease in the elderly

Introduction: Acute exacerbation of chronic obstructive pulmonary disease (AECOPD) is an important disease of hospitalized elderly patients, who often have electrolyte imbalances. This study was performed to analyze total serum calcium levels in elderly patients with AECOPD and identify the correlation between hypocalcemia and AECOPD. Methods: 153 elderly patients with AECOPD served as the observation group, and 115 healthy elderly people undergoing physical examinations served as the control group. Differences in the corrected serum calcium, albumin (ALB), and neutrophil/lymphocyte ratio (NLR) were analyzed between the observation and control groups before and after treatment. The incidence of hypocalcemia was compared among patients at different ages and with different pulmonary function classifications before treatment. The relationship between hypocalcemia and respiratory infection was analyzed. Differences in the pretreatment NLR, ALB, logarithm of the serum C-reactive protein level (LogCRP), and hospital stay were compared between patients with and without hypocalcemia. Results: The corrected serum calcium level (P < 0.001), NLR (P = 0.001) and albumin level (P < 0.001) were significantly different among the pretreatment group, post-treatment group, and control group. The serum calcium level, LogCRP, and NLR were significantly lower after than before treatment (P < 0.05). Significant differences in the incidence of hypocalcemia were found among patients of different ages (P = 0.002). The respiratory infection rate (P < 0.001), hospital stay (P < 0.001), NLR (P = 0.007), and LogCRP (P < 0.001) was higher in patients with than without hypocalcemia. However, the albumin level was lower in patients with than without hypocalcemia (P < 0.001). Conclusions: In elderly patients with AECOPD, hypocalcemia may be related to the disease progression, respiratory infection rate, and hospital stay of patients with AECOPD.

Efficacy of tamoxifen for the treatment of severe equine asthma

Background

Tamoxifen, a selective estrogen receptor modulator, decreased airway neutrophilia and improved clinical signs in an experimental model of equine asthma, and induced neutrophilic apoptosis in vitro.

Hypothesis/Objectives

Tamoxifen reduces airway neutrophilia and improves lung function in severe asthmatic horses.

Animals

Twelve severe asthmatic horses from a research herd.

Methods

Randomized controlled blinded study design. The effects of a 12‐day oral treatment with tamoxifen (0.22 mg/kg, q24h) or dexamethasone (0.06 mg/kg, q24h) on lung function, endoscopic tracheal mucus score and bronchoalveolar lavage fluid cytology were compared.

Results

Tamoxifen significantly improved the pulmonary resistance (R_L; mean reduction of 1.15 cm H₂O/L/s [CI: 0.29‐2.01, P = .007] on day 13), but had no effect on the other variables evaluated. Dexamethasone normalized lung function (mean reduction of R_L of 2.48 cm H₂O/L/s [CI: 1.54‐3.43, P < .0001] on day 13), without affecting airway neutrophilia.

Conclusions and Clinical Importance

Results of this study do not support the use of tamoxifen at the dose studied as an antineutrophilic medication in the treatment of asthmatic horses in chronic exacerbation.

Incidence of hypocalcemia and hypercalcemia in hospitalized patients: Is it changing?

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Disorders of calcium metabolism are frequently encountered in clinical practice.

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Hypocalcemia accounted for 27.72% and hypercalcemia for 4.74% of inpatients.

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Incidence of hypo- and hypercalcemia changed over time.

Disorders of calcium metabolism are frequently encountered in routine clinical practice. However limited data are available on the epidemiology of hypocalcemia and hypercalcemia in hospitalized patients. Our aim was to evaluate the frequency of hypocalcemia and hypercalcemia in hospitalized patients.

This is a retrospective study based on the laboratory results of all hospitalized subjects (n = 12,334) whose calcemia was determined between January 1st, 2011 and December 31st, 2014. Measurements of serum calcium were carried out by a single centralized laboratory. Hypocalcemia was defined as serum calcium levels <8.2 mg/dl and hypercalcemia as serum calcium levels >10.4 mg/dl. Albumin correction was applied to adjust serum calcium values.

Overall, hypocalcemia accounted for 27.72% (n = 3420) and hypercalcemia for 4.74% (n = 585) of the 12,334 inpatients. The highest prevalence of hypocalcemia was found in patients over 65 yr. (n = 2097, 61.31%) vs. younger subjects, while the highest prevalence of hypercalcemia was observed in patients aged 0–18 yr. (n = 380, 64.95%). Hypocalcemia was more often encountered in males (n = 1952, 57.07%) while no gender differences were found regarding hypercalcemia. Incidence of hypocalcemia changed over time varying from 35.42% (n = 1061) in 2011 to 21.93% (n = 672) in 2014 (r = −0.98; p = 0.01). Differently, incidence of hypercalcemia did not significantly increase significantly from 3.47% (n = 104) in 2011 to 6.92% (n = 211) in 2014 (r = 0.94; p = 0.052).

Despite increased awareness about electrolytes disturbance, physicians should consider calcium levels because of life-threatening consequences associated to hypo- and hypercalcemia. Patient’s gender and age could be associated to a different risk of calcium disturbance in hospitalized patients.

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.

Severe diabetic ketoacidosis complicated by hypocapnic seizure

In clinical practice, seizures independent of hypoglycemia are observed in patients with type 1 diabetes mellitus (T1DM) more frequently than expected by chance, suggesting a link. However, seizures during management of diabetic ketoacidosis (DKA) have generally been considered a bad prognostic factor, and usually associated with well-known biochemical or neurological complications. We present the case of a 17-year-old girl with known T1DM managed for severe DKA complicated by hypocapnic seizure. We review the literature on this rare occurrence as well as outline other possible differentials to consider when faced with the alarming combination of DKA and seizure.

Incidence, severity and prognosis associated with hypernatremia in dogs and cats

Background

Hypernatremia has been associated with substantial morbidity and death in human patients. The incidence and importance of hypernatremia in dogs and cats has not been determined.

Hypothesis/Objectives

To describe the incidence of and prognosis associated with hypernatremia in dogs and cats at a university teaching hospital.

Animals

A total of 16,691 dogs and 4,211 cats with measured blood or serum sodium concentration.

Methods

Retrospective study. Medical records of animals with a blood or serum sodium concentration measured during a 60‐month period were reviewed to determine the severity of hypernatremia and its associated case fatality rate. Cases with moderate (11–15 mmol/L above the reference range) or severe hypernatremia (≥16 mmol/L above the reference range) were further reviewed.

Results

A total of 957 dogs (5.7%) and 338 cats (8.0%) were diagnosed with hypernatremia. Case fatality rates of dogs and cats with hypernatremia was 20.6 and 28.1%, respectively compared to 4.4 and 4.5% with a normal blood or serum sodium concentration (P < .0001). The magnitude of hypernatremia was linearly associated with a higher case fatality rate (P < .0001). Hypernatremia was associated with a higher case fatality rate than hyponatremia. Among the animals with moderate or severe hypernatremia, 50% of dogs and 38.5% of cats presented with community‐acquired hypernatremia, and 50% of dogs and 61.5% of cats developed hospital‐acquired hypernatremia.

Conclusions and clinical importance

Hypernatremia was found infrequently in this population but was associated with increased case fatality rates in dogs and cats. Presence and severity of hypernatremia might be useful as a prognostic indicator.

Electrolyte disorders associated with the use of anticancer drugs

The use of anticancer drugs is beneficial for patients with malignancies but is frequently associated with the occurrence of electrolyte disorders, which can be hazardous and in many cases fatal. The review presents the electrolyte abnormalities that can occur with the use of anticancer drugs and provides the related mechanisms. Platinum-containing anticancer drugs induce hypomagnesemia, hypokalemia and hypocalcemia. Moreover, platinum-containing drugs are associated with hyponatremia, especially when combined with large volumes of hypotonic fluids aiming to prevent nephrotoxicity. Alkylating agents have been linked with the occurrence of hyponatremia [due to syndrome of inappropriate antidiuretic hormone secretion (SIADH)] and Fanconi's syndrome (hypophosphatemia, aminoaciduria, hypouricemia and/or glucosuria). Vinca alkaloids are associated with hyponatremia due to SIADH. Epidermal growth factor receptor monoclonal antibody inhibitors induce hypomagnesemia, hypokalemia and hypocalcemia. Other, monoclonal antibodies, such as cixutumumab, cause hyponatremia due to SIADH. Tyrosine kinase inhibitors are linked to hyponatremia and hypophosphatemia. Mammalian target of rapamycin inhibitors induce hyponatremia (due to aldosterone resistance), hypokalemia and hypophosphatemia. Other drugs such as immunomodulators or methotrexate have been also associated with hyponatremia. The administration of estrogens at high doses, streptozocin, azacitidine and suramin may induce hypophosphatemia. Finally, the drug-related tumor lysis syndrome is associated with hyperphosphatemia, hyperkalemia and hypocalcemia. The prevention of electrolyte derangements may lead to reduction of adverse events during the administration of anticancer drugs.

Parameters of Calcium Metabolism Fluctuated during Initiation or Changing of Antipsychotic Drugs

OBJECTIVE

Serum parameters of calcium homeostasis were measured based on previously published evidence linking osteoporotic fractures and/or bone/mineral loss with antipsychotics.

METHODS

Prospective, four-week, time-series trial was conducted and study population consisted of patients of both genders, aged 35-85 years, admitted within the routine practice, with acute psychotic symptoms, to whom an antipsychotic drug was either introduced or substituted. Serial measurements of serum calcium, phosphorous, magnesium, 25(OH)D, parathyroid hormone, calcitonin, osteocalcin and C-telopeptide were made from patient venous blood samples.

RESULTS

Calcium serum concentrations significantly decreased from baseline to the fourth week (2.42±0.12 vs. 2.33±0.16 mmol/L, p=0.022, n=25). The mean of all calcemia changes from the baseline was -2.6±5.7% (-24.1 to 7.7) with more decreases than increases (78 vs. 49, p=0.010) and more patents having negative sum of calcemia changes from baseline (n=28) than positive ones (n=10) (p=0.004). There were simultaneous falls of calcium and magnesium from baseline (63/15 vs. 23/26, p<0.001; OR=4.75, 95% CI 2.14-10.51), phosphorous (45/33 vs. 9/40, p<0.001; 6.06, 2.59-14.20) and 25(OH)D concentrations (57/21 vs. 13/35, p<0.001; 7.31, 3.25-16.42), respectively. Calcemia positively correlated with magnesemia, phosphatemia and 25(OH)D values. Parathyroid hormone and C-telopeptide showed only subtle oscillations of their absolute concentrations or changes from baseline; calcitonin and osteocalcin did not change. Adjustment of final calcemia trend (depletion/accumulation) for relevant risk factors, generally, did not change the results.

CONCLUSION

In patients with psychotic disorders and several risks for bone metabolism disturbances antipsychotic treatment was associated with the decrease of calcemia and changes in levels of the associated ions.

Severe hypocalcemia and life-threatening ventricular arrhytmias: case report and proposal of a diagnostic and therapeutic algorithm

Hypocalcemia is frequent in the setting of endocrine disorders, bone diseases and renal failure. When hypocalcemia is severe it can predispose to life-threatening ventricular arrhythmias; in such cases a rapid admission to hospital and a prompt correction of electrolyte imbalance are needed. We report the case of an old patient suffering from renal failure that was admitted to our cardiac step-down unit because of severe hypocalcemia associated with ventricular arrhythmias. Hypocalcemia was promptly treated and an endocrinologic consult was requested for investigating the causes of this electrolyte imbalance. Our experience suggests the creation of a new synergy between cardiologists and endocrinologists that led us to build a simple and schematic algorithm for the diagnosis and treatment of hypocalcemia.

Hypocalcaemia in patients with metastatic bone disease treated with denosumab

BACKGROUND

This analysis was performed to further characterise treatment-emergent hypocalcaemia in patients with bone metastases receiving denosumab.

METHODS

Laboratory abnormalities and adverse events of hypocalcaemia in patients with metastatic bone disease were analysed using data from three identically designed phase 3 trials of subcutaneous denosumab 120 mg (n = 2841) versus intravenous zoledronic acid 4 mg (n = 2836).

RESULTS

The overall incidence of laboratory events of hypocalcaemia grade ⩾ 2 was higher with denosumab (12.4%) than with zoledronic acid (5.3%). Hypocalcaemia events were primarily grade 2 in severity and usually occurred within the first 6 months of treatment. Patients who reported taking calcium and/or vitamin D supplements had a lower incidence of hypocalcaemia. Prostate cancer or small-cell lung cancer, reduced creatinine clearance and higher baseline bone turnover markers of urinary N-telopeptide of type I collagen (uNTx; > 50 versus ⩽ 50 nmol/mmol) and bone-specific alkaline phosphatase (BSAP; > 20.77 μg/L [median] versus ⩽ 20.77 μg/L) values were important risk factors for developing hypocalcaemia. The risk associated with increased baseline BSAP levels was greater among patients who had > 2 bone metastases at baseline versus those with ⩽ 2 bone metastases at baseline.

CONCLUSION

Hypocalcaemia was more frequent with denosumab versus zoledronic acid, consistent with denosumab's greater antiresorptive effect. Low serum calcium levels and potential vitamin D deficiency should be corrected before initiating treatment with a potent osteoclast inhibitor, and corrected serum calcium levels should be monitored during treatment. Adequate calcium and vitamin D intake appears to substantially reduce the risk of hypocalcaemia.

Organic anxiety in a woman with breast cancer receiving denosumab

Hypocalcemia can induce heterogeneous psychiatric manifestations, and its etiology can be multifactorial. Herein, we describe a patient who had previously undergone resection of parathyroid glands, who presented with extreme anxiety and hypocalcemia after denosumab treatment for cancer-related bone metastasis. The anxiety subsided soon after correction of her serum calcium level. When denosumab is prescribed for patients with predisposing factors of hypocalcemia, such as hypoparathyroidism, clinicians should be aware of symptomatic hypocalcemia.

Endocrine check-up in adolescents and indications for referral: A guide for health care providers

The American Academy of Pediatrics recommends that young people between the ages of 11 and 21 years should be seen annually by their pediatricians, since annual checkups can be an important opportunity for health evaluation and anticipatory guidance. Parents of infants and young children are accustomed to regularly visiting a pediatrician for their child's checkups. Unfortunately, when children reach the teen years, these annual checkups may decrease in frequency. In routine check-ups and medical office visits, particular attention should be paid to the possibility of a developmental or endocrine disorder. Early diagnosis and treatment may prevent medical complications in adulthood and foster age-appropriate development. Our purpose is to acquaint readers with the concept, based on current scientific understanding, that some endocrine disorders may be associated with a wide range of deleterious health consequences including an increased risk of hypertension and hyperlipidemia, increased risk of coronary artery disease, type 2 diabetes, significant anxiety and lack of self-esteem. Understanding the milestones and developmental stages of adolescence is essential for pediatricians and all other health providers who care for adolescents. Treating adolescents involves knowledge of a variety of medical, social and legal information; in addition, close working relationships must be established within the adolescent's network to create an effective care system. In summary, we underline the importance of a periodic endocrine checkup in adolescents in order to identify endocrine problems early and develop an approach to treatment for those patients who need help during this time. Indications for endocrine referral for professional and other healthcare providers are also included. These lists are clearly not intended to be comprehensive, but will hopefully serve as a guide for specific clinical circumstances.

Diabetes mellitus and electrolyte disorders

Diabetic patients frequently develop a constellation of electrolyte disorders. These disturbances are particularly common in decompensated diabetics, especially in the context of diabetic ketoacidosis or nonketotic hyperglycemic hyperosmolar syndrome. These patients are markedly potassium-, magnesium- and phosphate-depleted. Diabetes mellitus (DM) is linked to both hypo- and hyper-natremia reflecting the coexistence of hyperglycemia-related mechanisms, which tend to change serum sodium to opposite directions. The most important causal factor of chronic hyperkalemia in diabetic individuals is the syndrome of hyporeninemic hypoaldosteronism. Impaired renal function, potassium-sparing drugs, hypertonicity and insulin deficiency are also involved in the development of hyperkalemia. This article provides an overview of the electrolyte disturbances occurring in DM and describes the underlying mechanisms. This insight should pave the way for pathophysiology-directed therapy, thus contributing to the avoidance of the several deleterious effects associated with electrolyte disorders and their treatment.

The role of the gastrointestinal tract in calcium homeostasis and bone remodeling

While skeletal biology was approached in a rather isolated fashion in the past, an increasing understanding of the interplay between extraskeletal organs and bone remodeling has been obtained in recent years. This review will discuss recent advances in the field that have shed light on how the gastrointestinal tract and bone relate to each other. In particular, the importance of the GI tract in maintaining calcium homeostasis and skeletal integrity will be reviewed as impaired gastric acid production represents a major public health problem with possible implications for sufficient calcium absorption. Osteoporosis, the most prevalent bone disease worldwide, is caused not only by intrinsic defects affecting bone cell differentiation and function but also by a large set of extrinsic factors including hormonal disturbances, malnutrition, and iatrogenic drug application. Given the skeletal requirements of calcium, amino acids, and energy for bone turnover and renewal, it is not surprising that the gastrointestinal (GI) tract is of major importance for skeletal integrity.

Ionized hypocalcemia is an early event and is associated with organ dysfunction in children admitted to the intensive care unit

PURPOSE

The purpose was to determine the frequency and risk factors of ionized hypocalcemia and to evaluate this disturbance as a predictor of mortality in a pediatric intensive care unit (ICU).

MATERIALS AND METHODS

In a prospective cohort study, 337 children admitted consecutively to an ICU were monitored regarding serum ionized calcium concentrations during the first 10 days of admission. The following variables were analyzed as independent of hypocalcemia: age; malnutrition; sepsis; Pediatric Index of Mortality 2; first 3 days organ dysfunction score (Pediatric Logistic Organ Dysfunction); and use of steroids, furosemide, and anticonvulsants. Hypocalcemia was defined as a serum ionized calcium concentration less than 1.15 mmol/L.

RESULTS

The rate of hypocalcemia was 77.15%. In a multivariate model, higher Pediatric Logistic Organ Dysfunction scores during the first 3 days of ICU stay were independently associated with hypocalcemia (odds ratio, 2.24; 95% confidence interval, 1.23-4.07; P=.008). Medications associated with hypocalcemia were furosemide (dose≥2 mg/[kg d]) and methylprednisolone (dose≥2 mg/[kg d]). No significant association was found between hypocalcemia and 10-day mortality.

CONCLUSIONS

Ionized hypocalcemia is common during the ICU stay, particularly in the first 3 days of admission. This disturbance was not found to be a predictor of mortality, but it is independently associated with more severe organ dysfunction.

Extracellular magnesium and calcium reduce myotonia in ClC-1 inhibited rat muscle

Loss-of-function mutations in the ClC-1 Cl(-) channel trigger skeletal muscle hyperexcitability in myotonia congenita. For reasons that remain unclear, the severity of the myotonic symptoms can vary markedly even among patients with identical ClC-1 mutations, and may become exacerbated during pregnancy and with diuretic treatment. Since both these conditions are associated with hypomagnesemia and hypocalcemia, we explored whether extracellular Mg(2+) and Ca(2+) ([Mg(2+)]o and [Ca(2+)]o) can affect myotonia. Experimental myotonia was induced in isolated rat muscles by ClC-1 inhibition and effects of [Mg(2+)]o or [Ca(2+)]o on myotonic contractions were determined. Both cations dampened myotonia within their physiological concentration ranges. Thus, myotonic contractile activity was 6-fold larger at 0.3 than at 1.2 mM [Mg(2+)]o and 82-fold larger at 0.3 than at 1.27 mM [Ca(2+)]o. In intracellular recordings of action potentials, the threshold for action potential excitation was raised by 4-6 mV when [Mg(2+)]o was elevated from 0.6 to 3 mM, compatible with an increase in the depolarization of the membrane potential necessary to activate the Na(+) channels. Supporting this notion, mathematical simulations showed that myotonia went from appearing with normal Cl(-) channel function to disappearing in the absence of Cl(-) channel function when Na(+) channel activation was depolarized by 6 mV. In conclusion, variation in serum Mg(2+) and Ca(2+) may contribute to phenotypic variation in myotonia congenita patients.

Hypoparathyroidism in pregnancy

Pregnancy and lactation are associated with remarkable changes in calcium homeostasis, resulting from pregnancy-induced alterations in the production, metabolism and excretion of calcium and calcitropic hormones. Therefore, the clinical course of disorders affecting the parathyroid glands during pregnancy and lactation is often atypical. As the symptoms experienced by patients with parathyroid disorders are not specific, their diagnosis during gestation and breastfeeding may be sometimes very difficult. If left untreated, parathyroid disorders may pose a significant risk to the mother and fetus associated with increased perinatal and maternal morbidity and mortality. Hypoparathyroidism is a disorder rarely observed during pregnancy, resulting in most cases from surgical thyroidectomy. In our article, we present the case of a 32-year-old female with primary hypoparathyroidism diagnosed for the first time during pregnancy. We describe in details the treatment strategies undertaken in this patient and their impact on the outcome of pregnancy and lactation.

Medication-induced hypophosphatemia: a review

Hypophosphatemia (serum phosphorus concentration <2.5 mg/dl, 0.8 mmol/l), although rare in the general population, is commonly observed in hospitalized patients and may be associated with drug therapy. In fact, hypophosphatemia frequently develops in the course of treatment with drugs used in every-day clinical practice including diuretics and bisphosphonates. Proper diagnostic approach of patients with low serum phosphorus concentrations should involve a detailed medical history with special attention to the recent use of medications. The clinical manifestations of drug-induced hypophosphatemia are usually mild but might also be severe and potentially life-threatening. This review aims at a thorough understanding of the underlying pathophysiological mechanisms and risk factors of drug therapy-related hypophosphatemia thus allowing prevention and effective intervention strategies.

Endocrine and metabolic emergencies: hypocalcaemia

Hypocalcaemia is a common electrolyte disturbance, especially in the inpatient setting. There are a wide variety of causes of hypocalcaemia and correct management depends on the underlying diagnosis. However, acute hypocalcaemia is associated with significant morbidity and mortality and should be managed as a medical emergency. Chronic care of the hypocalcaemic patient is also briefly described, as this is an important opportunity to reduce further admissions related to both hypocalcaemic and hypercalcaemic presentations.