Frequency and aetiology of hypercalcaemia

Clinical characteristics of hypercalcemic crises in a tertiary children's hospital

BACKGROUND

Hypercalcemic crisis is considered a critical and fatal endocrine condition. To date, few reports have focused on hypercalcemic crises in children.

AIM

To explore the etiology and identify the clinical characteristics related to hypercalcemic crises in children.

METHODS

We enrolled 101 children diagnosed with hypercalcemia between January 1, 2016 and December 31, 2021, admitted to the Children's Hospital of Chongqing Medical University. Electronic medical records were reviewed to determine the causes and clinical characteristics of hypercalcemic crises.

RESULTS

Hypercalcemic crises occurred in 28 admissions during the 6-year period; 64% of the patients enrolled in the study were infants. The mean corrected total serum calcium was 4.6 ± 0.2 mmol/l. Tumor and hereditary diseases were found in 12 (43%) and 7 (25%) patients, respectively. The ratio of iatrogenic factors was 11% (3/28), and all 3 patients received a blood transfusion. The incidence of poor prognosis in the tumor cases was 50%. Timely intervention including hemodialysis, pamidronate, and etiological treatment was effective in decreasing calcium levels.

CONCLUSION

Hypercalcemic crisis is a serious electrolyte disturbance that has the potential for high mortality. The main causes are tumors and hereditary diseases in children. The lack of unique characteristics makes it difficult to recognize by medical caregivers. Early diagnosis and timely intervention could improve the prognosis.

Hypercalcemia and Neurological Symptoms: A Rare Presentation of Hyperfunctioning Parathyroid Adenoma in an Adolescent

Neuropsychiatric symptoms are rarely described as a manifestation of hyperparathyroidism, especially in children. We describe the case of an adolescent with hypercalcemia related to and hyperfunctioning parathyroid adenoma presenting with acute neuropsychiatric symptoms. A 14-year-old-girl presented into the Emergency Service Department because of an acute onset of marked asthenia, muscle weakness with difficulty in walking, and altered mental status, which included nonsensical speech. No other neurological signs were present. Abdominal, cardiac, and thoracic examination were unremarkable. There was no recent history of trauma or infection. Family history was negative for neurologic disorders. Her past medical history was unremarkable. A head CT scan showed negative results. The laboratory work-up showed elevated levels of calcium level (14.35 mg/dl; nv 9–11 mg/dl), parathyroid hormone (PTH; 184 pg/ml; nv 3.5–36.8 pg/ml), and creatinine (1.23 mg/dl; nv 0.45–0.75 mg/dl). Sodium, potassium, chloride, thyroid function, glycemia, and insulin values were normal. Neck ultrasonography showed a solid, oval, capsulated, hypoechoic neoformation, with discrete vascularization localized to the inferior pole of the right thyroid lobe, referring to parathyroid tissue. Scintigraphy revealed a hyperfunctioning parathyroid tissue at the inferior pole of the right thyroid lobe. Massive intravenous hydration and diuretic therapy were started. The signs and symptoms of hypercalcemia improved after the initiation of therapy. The patient was submitted to right cervicotomy and muscle sparing for the removal of the adenoma of the right superior parathyroid gland. After surgery, a decrease in PTH levels (<4 pg/ml) and calcium levels (9.1 mg/dl) was recorded. During follow-up, calcium values remained stable; a progressive normalization of PTH was obtained. The oral calcium therapy was suspended after 3 months from surgery. No neuropsychiatric symptoms recurred. An evaluation of the serum calcium level is mandatory in children and adolescents with unexplained neurological signs or symptoms, and a check for hyperparathyroidism should be considered.

Severe hypercalcemia associated with hypophosphatemia in very premature infants: a case report

BACKGROUND

Severe hypercalcemia is rare in newborns; even though often asymptomatic, it may have important sequelae. Hypophosphatemia can occur in infants experiencing intrauterine malnutrition, sepsis and early high-energy parenteral nutrition (PN) and can cause severe hypercalcemia through an unknown mechanism. Monitoring and supplementation of phosphate (PO4) and calcium (Ca) in the first week of life in preterm infants are still debated.

CASE PRESENTATION

We report on a female baby born at 29 weeks' gestation with intrauterine growth retardation (IUGR) experiencing sustained severe hypercalcemia (up to 24 mg/dl corrected Ca) due to hypophosphatemia while on phosphorus-free PN. Hypercalcemia did not improve after hyperhydration and furosemide but responded to infusion of PO4. Eventually, the infant experienced symptomatic hypocalcaemia (ionized Ca 3.4 mg/dl), likely exacerbated by contemporary infusion of albumin. Subsequently, a normalization of both parathyroid hormone (PTH) and alkaline phosphatase (ALP) was observed.

CONCLUSIONS

Although severe hypercalcemia is extremely rare in neonates, clinicians should be aware of the possible occurrence of this life-threatening condition in infants with or at risk to develop hypophosphatemia. Hypophosphatemic hypercalcemia can only be managed with infusion of PO4, with strict monitoring of Ca and PO4 concentrations.

Endocrine Diseases of Newborn: Epidemiology, Pathogenesis, Therapeutic Options, and Outcome "Current Insights Into Disorders of Calcium and Phosphate in the Newborn"

The physiology and regulation of bone minerals in the fetus and the newborn is significantly different from children and adults. The bone minerals calcium, phosphate and magnesium are all maintained at higher concentrations in utero to achieve adequate bone accretion. This is an integral component of normal fetal development which facilitates safe neonatal transition to post-natal life. When deciphering the cause of bone mineral disorders in newborns, the potential differential diagnosis list is broad and complex, including several extremely rare conditions. Also, significant discoveries including new embryological molecular genetic transcription factors, the role of active placental mineral transport, and hormone regulation factors have changed the understanding of calcium and phosphate homeostasis in the fetus and the newborn. This article will guide clinicians through an updated review of calcium and phosphate physiology, then review specific conditions pertinent to successful neonatal care. Furthermore, with the advancement of increasingly rapid molecular genetic testing, genomics will continue to play a greater role in this area of fetal diagnostics and prognostication.

A case of primary hyperparathyroidism due to an intrathymic ectopic parathyroid adenoma in a 15-year-old boy

Hypercalcemia due to primary hyperparathyroidism (PHPT) is uncommon in children. PHPT is typically caused by a single parathyroid adenoma. Ectopic parathyroid adenomas account for 6%-16% of all parathyroid adenomas and are rare in children but should be considered in cases that present with hypercalcemia. We report the case of a 15-year-old boy with PHPT due to an intrathymic ectopic parathyroid adenoma. Neck ultrasonography and Tc-99m-sestamibi (MIBI) scanning with single-photon emission computed tomography/computed tomography (SPECT/CT) revealed ectopic parathyroid adenoma in the thymus. Video-assisted thoracoscopic surgery was performed to remove the ectopic parathyroid adenoma. Pathology showed intrathymic ectopic parathyroid adenoma. After surgery, the patient's serum calcium level immediately normalized. Intact parathyroid hormone (iPTH) and alkaline phosphatase levels returned to normal ranges within 3 months. Delayed diagnosis of PHPT can cause end-organ damage; a timely diagnosis is especially critical to preserve bone and renal function. If ectopic parathyroid adenomas are well localized in preoperative imaging evaluation and intraoperative iPTH level decreases after resection, ectopic parathyroidectomy without bilateral neck exploration may be performed to avoid unnecessary morbidity.

A Rare and Potentially Fatal Etiology of Hypercalcemia in an Infant

Hypercalcemia is an uncommon finding in children. Hypercalcemia has various etiologies including parathyroid dependent and independent mechanisms. Increased activity of the 1-alpha-hydroxylase enzyme in granulomatous diseases is a well-defined but an extremely rare cause of hypercalcemia in pediatric patients, particularly in infants. We describe the case of an infant who presented with failure to thrive, hepatosplenomegaly, and hypercalcemia who was initially treated with steroids but was later diagnosed with disseminated histoplasmosis in the absence of an underlying immunodeficiency. Extra caution should be used before considering steroids for the treatment of hypercalcemia and, whenever possible, steroids should not be initiated until a definite etiology is identified.

Two Different Causes of Paediatric Hypercalcaemia

Paediatric hypercalcaemia is a rare condition which can be easily overlooked or misdiagnosed. We report two paediatric patients who presented to the Department of Paediatrics, Pardubice Hospital, Pardubice, Czech Republic, in 2009 and 2010, respectively. Each patient was diagnosed with hypercalcaemia due to a different cause. The first case involved a seven-month-old infant who presented with failure to thrive, vomiting and psychomotor retardation. Fluorescent in situ hybridisation revealed Williams-Beuren syndrome. The second patient was a 16-year-old girl with abdominal pain and renal colic due to hypercalcaemia-induced urolithiasis. High parathyroid hormone serum levels suggested primary hyperparathyroidism. An adenoma of the left upper parathyroid gland was diagnosed via technetium-99m-labelled methoxyisobutyl isonitrile single photon emission computed tomography and removed surgically. Hypercalcaemia should be considered in the differential diagnosis of various disease states, particularly among infants who fail to thrive or children with abdominal pain.

Childhood Sustained Hypercalcemia: A Diagnostic Challenge

OBJECTIVE

This study aimed to call attention to hypercalcemia, a rare finding in children which carries the potential of leading to serious complications without proper intervention.

METHODS

Diagnosis, treatment, and clinical course of children with sustained hypercalcemia admitted between the years 2006-2016 were reviewed. Group 1 [parathyroid hormone (PTH)-dependent] consisted of patients with high/unsuppressed PTH levels and group 2 (PTH-independent) included cases with normal/suppressed PTH levels.

RESULTS

Twenty patients (11 male, 9 female) with a median age of 6.25 (0.03-17.88) years were evaluated. Symptoms were mostly related with the gastrointestinal system, while six patients (30%) were asymptomatic. Physical examination findings were diverse, non-specific, and normal in four patients (20%). Median time of diagnosis was 45 (2-720) days. Patients were divided into group 1 (n=7) and group 2 (n=13). Most frequent etiologies were primary hyperparathyroidism (n=5), idiopathic infantile hypercalcemia (IIH) (n=5), and malignancy (n=4). A moderate positive correlation was noted between serum calcium and creatinine levels (r=0.53, p=0.02). Nephrocalcinosis was the most common complication (n=9) (45%). Treatment was not implemented in 2 patients with mild hypercalcemia, while other patients received medical treatment ± surgery. Treatment-resistant patients were cases of malignancies and neonatal severe hyperparathyroidism. Long-term follow-up displayed resistant hypercalciuria in three infants diagnosed as IIH.

CONCLUSION

Many patients with childhood hypercalcemia are asymptomatic or exhibit a non-specific and heterogeneous clinical presentation, resulting in delayed diagnosis. Mild cases may not be recognized, while symptoms may be missed in the presence of accompanying illnesses. Nevertheless, serious complications may only be avoided with prompt diagnosis and intervention.

Hypercalcemic Disorders in Children

Hypercalcemia is defined as a serum calcium concentration that is greater than two standard deviations above the normal mean, which in children may vary with age and sex, reflecting changes in the normal physiology at each developmental stage. Hypercalcemic disorders in children may present with hypotonia, poor feeding, vomiting, constipation, abdominal pain, lethargy, polyuria, dehydration, failure to thrive, and seizures. In severe cases renal failure, pancreatitis and reduced consciousness may also occur and older children and adolescents may present with psychiatric symptoms. The causes of hypercalcemia in children can be classified as parathyroid hormone (PTH)-dependent or PTH-independent, and may be congenital or acquired. PTH-independent hypercalcemia, ie, hypercalcemia associated with a suppressed PTH, is commoner in children than PTH-dependent hypercalcemia. Acquired causes of PTH-independent hypercalcemia in children include hypervitaminosis; granulomatous disorders, and endocrinopathies. Congenital syndromes associated with PTH-independent hypercalcemia include idiopathic infantile hypercalcemia (IIH), William's syndrome, and inborn errors of metabolism. PTH-dependent hypercalcemia is usually caused by parathyroid tumors, which may give rise to primary hyperparathyroidism (PHPT) or tertiary hyperparathyroidism, which usually arises in association with chronic renal failure and in the treatment of hypophosphatemic rickets. Acquired causes of PTH-dependent hypercalcemia in neonates include maternal hypocalcemia and extracorporeal membrane oxygenation. PHPT usually occurs as an isolated nonsyndromic and nonhereditary endocrinopathy, but may also occur as a hereditary hypercalcemic disorder such as familial hypocalciuric hypercalcemia, neonatal severe primary hyperparathyroidism, and familial isolated primary hyperparathyroidism, and less commonly, as part of inherited complex syndromic disorders such as multiple endocrine neoplasia (MEN). Advances in identifying the genetic causes have resulted in increased understanding of the underlying biological pathways and improvements in diagnosis. The management of symptomatic hypercalcemia includes interventions such as fluids, antiresorptive medications, and parathyroid surgery. This article presents a clinical, biochemical, and genetic approach to investigating the causes of pediatric hypercalcemia. © 2017 American Society for Bone and Mineral Research.

Infants With Congenital Adrenal Hyperplasia Are at Risk for Hypercalcemia, Hypercalciuria, and Nephrocalcinosis

Context:

Hypercalcemia is reported as a rare finding in adrenal insufficiency, but is not well described in congenital adrenal hyperplasia (CAH).

Methods:

A retrospective chart review was conducted of patients with CAH diagnosed before the age of 2 years who had at least one recorded serum calcium measurement. Data from birth to 6 years of age were reviewed.

Results:

Of the 40 patients who met inclusion criteria, 33 (82.5%) had at least one elevated calcium concentration and 21 (53%) had two or more elevated calcium concentrations. Of the 126 elevated serum calcium concentrations, the median was 10.9 mg/dL (range, 10.6 to 14.2 mg/dL). Median age at the last elevated calcium measurement was 5 months (range, 0.3 to 46 months). Serum calcium concentration was inversely related to age (r = −0.124; P = 0.004). Overall, calcium level positively correlated with 17-hydroxyprogesterone (17OHP) concentration (r = 0.170; P = 0.003), and this remained significant after adjusting for age (P < 0.05). However, patients had hypercalcemia with both high and low 17OHP concentrations. Serum calcium concentration also was positively related to glucocorticoid (r = 0.196; P = 0.012) and fludrocortisone (r = 0.229; P = 0.003) doses, and remained significant after age adjustment. Only seven patients were evaluated for hypercalciuria. Of these, six had at least one period of documented hypercalciuria. Three patients had nephrocalcinosis on renal ultrasound.

Conclusion:

Children with CAH are at risk for developing hypercalcemia, hypercalciuria, and nephrocalcinosis. Further studies are needed to determine the broader prevalence and the etiology of hypercalcemia in CAH.

Giant parathyroid adenoma associated with severe hypercalcemia in an adolescent patient

BACKGROUND

The objective of this study is to bring attention to the importance of differential diagnosis in adolescent patients with skeletal involvement and hypercalcemia.

CASE

A 17-year-old male patient with a complaint of severe leg pain was admitted to our hospital. Seven months before he had a fracture of his distal humerus after falling on to his left shoulder and was treated conservatively. Five months previously, he had a rupture of his quadriceps tendon. Magnetic resonance imaging (MRI) was performed for the quadriceps tendon rupture and was evaluated as polyostotic fibrous dysplasia (PFD). Doctors decided to operate for the ruptured tendon but they detected severe hypercalcemia in the pre-operative blood tests and noticed that the main disease was primary hyper-parathyroidisim (PHPT) which was caused by a giant parathyroid adenoma. Conclusions Giant parathyroid adenoma can present in adolescent patients with multiple bone lesions and severe hypercalcemia. PHPT should be considered in the differential diagnosis of pathological bone fractures and benign bone tumors in every age. This may prevent patients from miss or delayed diagnosis of PHPT.