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Neonatal Hypercalcemia


Kevin C. Dysart

, MD, Nemours/Alfred I. duPont Hospital for Children

Reviewed/Revised Mar 2021 | Modified Sep 2022

Hypercalcemia is total serum calcium > 12 mg/dL (> 3 mmol/L) or ionized calcium > 6 mg/dL (> 1.5 mmol/L). The most common cause is iatrogenic. Gastrointestinal signs may occur (eg, anorexia, vomiting, constipation) and sometimes lethargy or seizures. Treatment is IV normal saline plus furosemide and sometimes corticosteroids, calcitonin, and bisphosphonates.

Etiology of Neonatal Hypercalcemia

The most common cause of neonatal hypercalcemia is

  • Iatrogenic

Iatrogenic causes usually involve excess calcium or vitamin D, or phosphate deprivation, which can result from prolonged feeding with incorrectly prepared formula.

Other causes of neonatal hypercalcemia include

  • Maternal hypoparathyroidism

  • Subcutaneous fat necrosis

  • Parathyroid hyperplasia

  • Abnormal renal function

  • Williams syndrome

  • Idiopathic

Maternal hypoparathyroidism or maternal hypocalcemia may cause secondary fetal hyperparathyroidism, with changes in fetal mineralization (eg, osteopenia).

Subcutaneous fat necrosis may occur after major trauma and causes hypercalcemia that usually resolves spontaneously.

Neonatal hyperparathyroidism is very rare.

Williams syndrome's key features include supravalvular aortic stenosis Aortic Stenosis Aortic stenosis (AS) is narrowing of the aortic valve, obstructing blood flow from the left ventricle to the ascending aorta during systole. Causes include a congenital bicuspid valve, idiopathic... read more Aortic Stenosis , pulmonary valvular or peripheral pulmonary artery stenosis, atrial septal defect Atrial Septal Defect (ASD) An atrial septal defect (ASD) is an opening in the interatrial septum, causing a left-to-right shunt and volume overload of the right atrium and right ventricle. Children are rarely symptomatic... read more and/or ventricular septal defect Ventricular Septal Defect (VSD) A ventricular septal defect (VSD) is an opening in the interventricular septum, causing a shunt between ventricles. Large defects result in a significant left-to-right shunt and cause dyspnea... read more Ventricular Septal Defect (VSD) , renal artery stenosis Renal Artery Stenosis and Occlusion Renal artery stenosis is a decrease in blood flow through one or both of the main renal arteries or their branches. Renal artery occlusion is a complete blockage of blood flow through one or... read more Renal Artery Stenosis and Occlusion , aortic anomalies, elfin facies, and hypercalcemia of unknown pathophysiology; infants may also be small for gestational age Small-for-Gestational-Age (SGA) Infant Infants whose weight is < the 10th percentile for gestational age are classified as small for gestational age. Complications include perinatal asphyxia, meconium aspiration, polycythemia... read more , and hypercalcemia can be noted early in infancy, usually resolving by age 12 months.

Idiopathic neonatal hypercalcemia is a diagnosis of exclusion and is difficult to differentiate from Williams syndrome and often requires genetic testing.

Symptoms and Signs of Neonatal Hypercalcemia

Symptoms and signs of neonatal hypercalcemia may be noted when total serum calcium is > 12 mg/dL (> 3 mmol/L). These signs can include anorexia, gastroesophageal reflux, nausea, vomiting, lethargy or seizures or generalized irritability, and hypertension. Other symptoms and signs include constipation, abdominal pain, dehydration, feeding intolerance, and failure to thrive. Some neonates have weakness. With subcutaneous fat necrosis, firm purple nodules may be observed on trunk, buttocks, or legs.

Diagnosis of Neonatal Hypercalcemia

  • Total or ionized serum calcium level

Diagnosis of neonatal hypercalcemia is made by measuring the total or ionized serum calcium level.

Treatment of Neonatal Hypercalcemia

  • IV normal saline plus furosemide

  • Sometimes corticosteroids, calcitonin, and bisphosphonates

Marked elevation of serum calcium may be treated with normal saline 20 mL/kg IV plus furosemide 2 mg/kg IV and, when persistent, with corticosteroids and calcitonin. Bisphosphonates are also increasingly used in this context (eg, etidronate by mouth or pamidronate IV). Treatment of subcutaneous fat necrosis is with a low-calcium formula; fluids, furosemide, calcitonin, and corticosteroids are used as indicated by the degree of hypercalcemia.

Fetal hypercalcemia caused by maternal hypoparathyroidism can be treated expectantly, because it usually resolves spontaneously within a few weeks.

Treatment of chronic conditions includes a low-calcium, low-vitamin D formula.

Drugs Mentioned In This Article

Drug Name Select Trade
Delone , FUROSCIX, Lasix
Fortical , Miacalcin
Calcidol, Calciferol, D3 Vitamin, DECARA, Deltalin, Dialyvite Vitamin D, Dialyvite Vitamin D3, Drisdol, D-Vita, Enfamil D-Vi-Sol, Ergo D, Fiber with Vitamin D3 Gummies Gluten-Free, Happy Sunshine Vitamin D3, MAXIMUM D3, PureMark Naturals Vitamin D, Replesta, Replesta Children's, Super Happy SUNSHINE Vitamin D3, Thera-D 2000, Thera-D 4000, Thera-D Rapid Repletion, THERA-D SPORT, UpSpring Baby Vitamin D, UpSpring Baby Vitamin D3, YumVs, YumVs Kids ZERO, YumVs ZERO
NOTE: This is the Professional Version. CONSUMERS: View Consumer Version
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