Hypercalcemia: a consultant's approach

Calcifediol and paricalcitol as adjunctive therapies for HSV-1 keratitis and corneal perforation: A case report

RATIONALE

Herpes simplex virus 1 establishes a latent infection in trigeminal ganglia. Reactivation causes cold sores, as well as viral keratitis. The purpose of this study was to report potential benefits of using active vitamin D receptor ligands (VDR-agonists) as adjunctive therapies for the treatment of infectious corneal perforations, and prevention of HSV recurrence.

PATIENT CONCERNS

A 57-year-old female with a past history of episodic, poorly-healing, corneal erosions, recurring orolabial herpetic lesions, as well as PCR-confirmed recurrences of herpes simplex keratitis presented with a burning sensation and slight pain in the right eye. Examination indicated HSV keratitis. Topical antibiotic and oral antiviral treatments were prescribed. Despite these standard-of-care treatments, a perforated corneal ulcer ensued.

DIAGNOSES

Corneal perforation associated with HSV-1 keratitis recurrence, later confirmed by PCR analysis of corneal scrapings.

INTERVENTIONS

Corneal perforation was treated with a human fibrin glue, fortified with multilayered amniotic membrane transplant, as well as a therapeutical contact lens. Following surgery, calcifediol and paricalcitol were started as oral adjunctive therapies in an attempt to boost tissue regeneration and innate-immunity within the slow-healing cornea. Anterior segment optical-coherence tomography was used to measure corneal thickness. Frequent follow-ups with various specialists allowed for comprehensive patient evaluation, and meticulous screening for any signs indicating potential HSV-1 recurrence.

OUTCOMES

Following calcifediol-paricalcitol therapy corneal thickening, and re-epithelization ensued. During combined calcifediol-paricalcitol therapy, the patient has had no recurrence of herpes simplex keratitis, or orolabial herpes lesions.

LESSONS

Corneal stabilization avoided a high-risk, full-thickness corneal transplantation, facilitating future cataract surgery, and allowing for some degree of visual recovery in this eye.

The identification and correction of pseudohypercalcemia

Background

We found that a subset of patients with monoclonal gammopathy exhibited hypercalcemia without apparent causes or clinical manifestations In a cohort of 289 monoclonal gammopathy patients, 2.4% presented with such atypical hypercalcemia, with one notable case exhibiting normal ionized calcium levels, suggesting the presence of pseudohypercalcemia.

Objective

The aim of this study is to elucidate the factors contributing to pseudohypercalcemia in monoclonal gammopathy and to develop a novel globulin-corrected calcium formula for clinical application.

Methods

This observational study enrolled 110 monoclonal gammopathy patients from our center. An additional 33 patients were recruited to validate the newly proposed formula. Univariate analysis identified potential risk factors. And multivariate logistic regression identified definitive influential factors. The determined influential factors were utilized to develop a formula by multiple linear regression, which was validated by a paired t-test and the Youden index.

Results

This study found that globulin was a risk factor for pseudohypercalcemia. It revealed that pseudohypercalcemia should be considered in patients with globulin levels ≥61 g/L (P=0.014). Both albumin and globulin were confirmed as independent factors associated with bound calcium. Given that, we developed a formula to correct ionized calcium levels, which was consistent with ionized calcium tested by blood gas analysis. The diagnostic accuracy of the new formula (Youden index is 0.906) is better than the traditional formula (Youden index is 0.906). Interestingly, all monoclonal immunoglobulin types, except for light chains, showed an equal propensity to develop pseudohypercalcemia (P=0.306). It also showed a linear correlation between IgA, IgG, and IgM and bound calcium.

Conclusion

This study confirmed that elevated globulin affects serum total calcium and offered the threshold of globulin ≥ 61 g/L in the differential diagnosis of peudohypercalcemia from hypercalcemia. The new formula based on albumin and globulin was developed, which was verified to be better than the traditional formula for correctly diagnosing hypercalcemia. In addition, we found that neither light chains nor heavy chains of monoclonal immunoglobulin alone can result in pseudohypercalcemia.

Pulp stones: any relevance with the levels of serum calcium, parathyroid hormone, vitamin D and uric acid

Objectives

This study evaluated the effect of serum calcium, parathyroid hormone (PTH), vitamin D, and uric acid levels on pulp stone formation.

Materials and Methods

Patients who were admitted to the Muğla Sıtkı Koçman University, Faculty of Dentistry, Department of Oral and Maxillofacial Radiology for dental complaints were registered. Among these patients, individuals who had routine biochemical tests at the same period in the Outpatient Clinics of Muğla Sıtkı Koçman University Training and Research Hospital were included in the study. The patients with at least 1 pulp stone on panoramic radiographs recorded as the "pulp stone group" while patients without any pulp stones were the "control group". Demographic data and serum levels of calcium, PTH, vitamin D, and uric acid were retrospectively evaluated in both groups. Student t-test or Mann-Whitney U test was used to evaluate the differences between the groups.

Results

Among 151 patients, dental pulp stone was detected in 53.6% of patients, and 82.7% of these patients were female. Female sex and pulp stone formation were significantly associated (p = 0.001). The mean age of the pulp stone group was 43.9, while it was 39.9 in the control group, without any significant correlation between age and pulp stone (p > 0.05). Similarly, there were no significant differences in serum levels of PTH, vitamin D, uric acid and calcium between groups (p > 0.05).

Conclusions

According to the present study, the effect of dental factors rather than systemic factors should be considered primarily in pulp stone formation.

Clinical Profile and Outcomes of Patients With Hypercalcemia in an Indian Tertiary Care Center

Hypercalcemia is a complex medical condition characterized by elevated levels of serum calcium (>10.5 mg/dL) in the bloodstream, often arising from various underlying etiologies. This condition presents a significant clinical challenge due to its diverse clinical manifestations and potential for serious complications. Profiling and understanding hypercalcemia is essential for accurate diagnosis, appropriate management, and improved patient outcomes. In this study, we delve into the comprehensive profiling of hypercalcemia, encompassing its epidemiology, pathophysiology, clinical presentation, and diagnostic approaches. We explore the multifaceted etiological factors contributing to hypercalcemia, including primary hyperparathyroidism, malignancies, granulomatous disorders, medications, and more. We highlight the intricate interplay between parathyroid hormone, vitamin D, and other regulatory mechanisms that influence calcium homeostasis, shedding light on the underlying molecular pathways. Furthermore, we discuss the diverse clinical manifestations of hypercalcemia, ranging from asymptomatic cases to severe, life-threatening complications involving the renal, gastrointestinal, cardiovascular, and neuromuscular systems. Accurate diagnosis is pivotal, and we evaluate the array of laboratory tests, imaging modalities, and specialized assays that aid in identifying the root cause of hypercalcemia. We emphasize the importance of a systematic approach to differential diagnosis and the significance of risk stratification to guide clinical decision-making. The evolving landscape of treatment options for hypercalcemia is also explored, encompassing both acute management and long-term strategies tailored to the underlying etiology. We assess the role of hydration, pharmacological agents, and surgical interventions, underscoring the need for individualized therapeutic plans based on the severity and underlying cause of hypercalcemia. In conclusion, the profiling of hypercalcemia is a multidimensional endeavor that necessitates a comprehensive understanding of its underlying mechanisms, diverse clinical presentations, and diagnostic intricacies. This study intends to serve as a valuable resource for healthcare professionals, offering insights into the complex terrain of hypercalcemia.

Severe neonatal hypercalcemia revealing congenital mesoblastic nephroma: A case report and management of neonatal hypercalcemia: Severe neonatal hypercalcemia revealing congenital mesoblastic nephroma

Congenital mesoblastic nephroma is a rare pediatric renal tumor and has been reported in patients presenting with palpable abdominal mass, arterial hypertension, hematuria, polyuria, or hypercalcemia. Here we present the case of a 1-month-old neonate with suspected parathyroid hormone (PTH)-related peptide (PTH-rp)-mediated severe hypercalcemia revealing congenital mesoblastic nephroma. Preoperatively, hypercalcemia was corrected with hydration, furosemide, pamidronate, and low-calcium infant formula. Unilateral nephrectomy led to the resolution of hypercalcemia, transient hyperparathyroidism, and transient vitamin D and mineral supplementation. We conclude that congenital mesoblastic nephroma can secrete PTH-rp that can cause severe hypercalcemia.

Genetic causes of neonatal and infantile hypercalcaemia

The causes of hypercalcaemia in the neonate and infant are varied, and often distinct from those in older children and adults. Hypercalcaemia presents clinically with a range of symptoms including failure to thrive, poor feeding, constipation, polyuria, irritability, lethargy, seizures and hypotonia. When hypercalcaemia is suspected, an accurate diagnosis will require an evaluation of potential causes (e.g. family history) and assessment for physical features (such as dysmorphology, or subcutaneous fat deposits), as well as biochemical measurements, including total and ionised serum calcium, serum phosphate, creatinine and albumin, intact parathyroid hormone (PTH), vitamin D metabolites and urinary calcium, phosphate and creatinine. The causes of neonatal hypercalcaemia can be classified into high or low PTH disorders. Disorders associated with high serum PTH include neonatal severe hyperparathyroidism, familial hypocalciuric hypercalcaemia and Jansen's metaphyseal chondrodysplasia. Conditions associated with low serum PTH include idiopathic infantile hypercalcaemia, Williams-Beuren syndrome and inborn errors of metabolism, including hypophosphatasia. Maternal hypocalcaemia and dietary factors and several rare endocrine disorders can also influence neonatal serum calcium levels. This review will focus on the common causes of hypercalcaemia in neonates and young infants, considering maternal, dietary, and genetic causes of calcium dysregulation. The clinical presentation and treatment of patients with these disorders will be discussed.

Case report: Histoplasmosis presenting as asymptomatic hypercalcemia detected on routine laboratory testing in a pediatric kidney transplant recipient

Among all infections occurring in pediatric kidney transplant recipients, approximately 1%-5% are fungal. Most fungal infections occur in the first 6 months following kidney transplantation. We present the case of a 15-year-old boy with a history of a kidney transplant 4 years ago, who was found to have asymptomatic moderate hypercalcemia on routine laboratory testing, along with an acute deterioration of his kidney function markers. The cause of his acute kidney injury was likely related to hypercalcemia. An extensive workup for hypercalcemia revealed infection with Histoplasma capsulatum (histoplasmosis) with multiple pulmonary nodules. Hypercalcemia that was initially refractory to medical management resolved after initiating the antifungal treatment. Fungal granulomatous infections such as histoplasmosis should be considered in the differential diagnosis of hypercalcemia in an asymptomatic pediatric kidney transplant recipient.

Mechanisms of acute hypercalcemia in pediatric patients following the interruption of Denosumab

PURPOSE

Denosumab is a fully human monoclonal anti-RANK-L antibody that is clinically used to counteract the bone loss induced by exacerbated osteoclast activity. Indeed, its binding to RANK-L prevents the interaction RANK-L/receptor RANK that is essential for osteoclastogenesis and bone resorbing activity. Although there are many medications available to treat bone loss diseases, including bisphosphonates, Denosumab is highly effective since it reduces the bone erosion. The use in pediatric patients is safe. However, some concerns are related to the interruption of the treatment. Indeed, in this study, we reported hypercalcemia in two pediatric patients and alterations of circulating osteoclast precursors.

METHODS

Peripheral Blood Mononuclear Cells (PBMC) were isolated from two pediatric patients with hypercalcemia after Denosumab interruption and from 10 controls. Cytofluorimetric analysis and in vitro osteoclastogenesis experiments were performed.

RESULTS

Increase of CD16^-CD14⁺CD11b⁺ cells was revealed in PBMC from patients reflecting the enhanced in vitro osteoclastogenesis.

CONCLUSION

Our data suggest that precautions must be taken when Denosumab therapy is interrupted and gradual decrease of dose and/or timing of treatment should be performed. To prevent the onset of hypercalcemia that could be in the discontinuation phase, cytofluorimetric analysis of PBMC should be performed to evaluate osteoclast precursors.

Neonatal Hypocalcemia in the Infant of a Diabetic Mother

Neonatal hypocalcemia (NHC) is one of the most common disorders of calcium metabolism in infants admitted to the NICU. Presentation can range from asymptomatic to generalized seizures or tetany. In this case study, an infant with NHC is presented along with an overview of the pathophysiology, prevalence, diagnosis, and management of NHC for neonatal clinicians.

Severe hypercalcaemia and acute renal failure in an infant with subcutaneous fat necrosis

Subcutaneous fat necrosis (SFN) in the newborn is a form of panniculitis which presents with erythematous nodules and indurated plaques. Severe life-threatening hypercalcaemia can occur as a late complication. A 2-month-old girl presented with severe hypercalcaemia and acute renal injury as a complication of SFN. She was admitted to hospital with the chief complaint of failure to thrive. She had a history of therapeutic hypothermia. After successful treatment of the hypercalcaemia with bisphosphonates, the acute renal injury recovered spontaneously. In neonates with SFN, acute renal injury is a rare complication of hypercalcaemia. Timely prevention of the complications of hypercalcaemia in SFN is essential.

Forget the phosphorus: A case of hypervitaminosis D-induced symptomatic hypercalcemia

Hypercalcemia is a frequently encountered electrolyte abnormality with a well-described differential diagnosis and classic algorithm for evaluation. The treatment for hypercalcemia is dependent on the underlying etiology. Hypervitaminosis D is an uncommon cause of hypercalcemia, but the use of vitamin D supplementation has expanded and case reports of supplemental vitamin D induced hypercalcemia have become more frequent. We present a case of hypervitaminosis D-induced altered mental status where diagnosis was delayed and additional invasive testing was performed due to an assumption regarding phosphatemia.

Severe hypercalcemia and a pelvic brown tumor in an adolescent with primary hyperparathyroidism: a case report

BACKGROUND

Primary hyperparathyroidism may present in a myriad of manners, varying from an incidental asymptomatic biochemical finding to gastrointestinal, psychiatric, renal, and bone manifestations. While hyperparathyroidism remains a rare diagnosis in the pediatric population, the initial approach to diagnosis and management of hypercalcemia in children is imperative for the general pediatrician. Herein, we describe an adolescent who presented with a lytic bone lesion and severe, symptomatic hypercalcemia due to primary hyperparathyroidism.

CASE PRESENTATION

A 14-year-old male presented with vomiting, constipation, abdominal pain, and lethargy. He had an elevated total corrected calcium of 4.3 mmol/L. He was found to have a large pelvic lytic tumor consistent with a brown tumor due to primary hyperparathyroidism. He received pharmacologic therapy for stabilization of his hypercalcemia, including intravenous saline, intravenous bisphosphonates, and calcitonin. He subsequently received definitive therapy via parathyroidectomy and his post-operative course was complicated by hungry bone syndrome. Long-term follow-up has found full resolution of the lytic lesion and restored calcium homeostasis.

CONCLUSIONS

We present this case to highlight the possible presentations of hypercalcemia and hyperparathyroidism that are essential for a general pediatrician to recognize to ensure prompt diagnosis and management. Evaluation for hypercalcemia should be considered in patients with suggestive symptoms and physical exam findings. To our knowledge, this patient represents the first reported pediatric case of a pelvic brown tumor in an adolescent. While the multi-systemic complications of hyperparathyroidism may be quite severe, swift and appropriate management may mitigate these clinical outcomes.

Impact of admission serum ionized calcium levels on risk of acute kidney injury in hospitalized patients

This study aimed to investigate the risk of acute kidney injury (AKI) in hospitalized patients based on admission serum ionized calcium levels. This is a cohort study of all hospitalized adult patients, from January 2009 to December 2013 at a tertiary referral hospital, who had available serum ionized calcium at the time of admission. We excluded patients who had end-stage kidney disease or AKI at admission. We stratified admission serum ionized calcium into 6 groups; ≤ 4.39, 4.40-4.59, 4.60-4.79, 4.80-4.99, 5.00-5.19, and ≥ 5.20 mg/dL. We used serum creatinine criterion of KDIGO definition for diagnosis of AKI. We performed logistic regression analysis to assess the risk of in-hospital AKI occurrence based on admission serum ionized calcium, using serum ionized calcium of 5.00-5.19 mg/dL as the reference group. We studied a total of 25,844 hospitalized patients. Of these, 3,294 (12.7%) developed AKI in hospital, and 622 (2.4%) had AKI stage 2 or 3. We observed a U-shaped association between admission serum ionized calcium and in-hospital AKI, with nadir in-hospital AKI was in serum ionized calcium of 5.00-5.19 mg/dL. After adjustment for confounders, low serum ionized calcium of 4.40-4.59, ≤ 4.39 mg/dL and elevated serum ionized calcium ≥ 5.20 mg/dL were associated with increased risk of AKI with odds ratio of 1.33 (95% CI 1.14-1.56), 1.45 (95% CI 1.21-1.74), and 1.26 (95% CI 1.04-1.54), respectively. Both hypocalcemia, and hypercalcemia at the time of admission were associated with an increased risk of hospital-acquired AKI.

Pediatric parathyroid disease

Parathyroid glands are critical for calcium and phosphate homeostasis. Parathyroid disease is relatively rare in the pediatric population, but there are some important pediatric-specific considerations and conditions. This article reviews parathyroid physiology, disorders of hyper- and hypo- function, operative management, and uniquely pediatric diagnoses such as neonatal severe hyperparathyroidism. Advances in preoperative imaging, intra-operative gland identification, and management of post-thyroidectomy hypocalcemia are also presented in detail. This article combines a review of fundamentals with recent advances in care, emphasizing pediatric-specific publications.

A Case Study of Severe Hypercalcemia Secondary to Subcutaneous Fat Necrosis: A Diagnosis of Exclusion

Subcutaneous fat necrosis (SCFN) is a rare complication, usually occurring in otherwise healthy full-term infants who have experienced some level of trauma that causes ischemic injury to adipose tissue. Tissue injury usually occurs in areas of the body that are exposed to excessive pressure as during delivery. Tissue injury has also been described secondary to therapeutic cooling. This case study presents an infant who received whole body cooling for hypoxic ischemic injury and later developed severe hypercalcemia at one month of age without the skin lesions consistent with SCFN. The differential diagnosis for hypercalcemia and how it relates to SCFN is presented, as well as clinical presentation, treatment, and prognosis.

Use of calcimimetics in children with normal kidney function

The calcium-sensing receptor (CaSR) plays an important role in the homeostasis of serum ionized calcium by regulating parathyroid hormone (PTH) secretion and tubular calcium handling. Calcimimetics, which act by allosteric modulation of the CaSR, mimic hypercalcemia resulting in suppression of PTH release and increase in calciuria. Mostly used in children to treat secondary hyperparathyroidism associated with advanced renal failure, we have shown that calcimimetics can also be successfully used in children with bone and mineral disorders in which elevated PTH plays a detrimental role in skeletal pathophysiology in the face of normal kidney function. The current review briefly discusses the role of the CaSR and calcimimetics in calcium homeostasis, and then addresses the potential applications of calcimimetics in children with normal kidney function with disorders in which suppression of PTH is beneficial.