{
"topic": "Hypocalcemia",
"slug": "hypocalcemia",
"category_id": 14940,
"passage_count": 14,
"source_chars": 11834,
"enough_material": true,
"references": [
{
"title": "Cover",
"author": "Vitalsource Download",
"pages": [
865,
8198,
8208
]
},
{
"title": "CURRENT Diagnosis and Treatment Pediatrics, Twenty-Fourth Edition",
"author": "Hay, William W., Levin, Myron J., Deterding, Robin R., Abzug, Mark J.",
"pages": [
98,
1068
]
},
{
"title": "Zitelli and Davis' Atlas of Pediatric Physical Diagnosis: Expert Consult - Online",
"author": null,
"pages": [
408
]
},
{
"title": "MedStudy Pediatrics Core 11th Edition 2024-2025",
"author": null,
"pages": [
553,
630
]
},
{
"title": "Gomella's Neonatology: Management, Procedures, On-Call Problems, Diseases, and Drugs, Eighth Edition",
"author": "Tricia Lacy Gomella, Fabien G. Eyal and Fayez Bany-Mohammed",
"pages": [
866,
867,
870
]
},
{
"title": "Ghai Essential Pediatrics, 9e (Vinod K Paul, Arvind Bagga)",
"author": "CamScanner",
"pages": [
523
]
},
{
"title": "Kliegman R. Nelson Textbook of Pediatrics 2-Volume Set 22ed 2024",
"author": null,
"pages": [
1067
]
}
],
"passages": [
{
"source": "Cover, p. 8208",
"text": "## **HYPERCALCEMIA** Hypercalcemia is defined as a total serum calcium concentration greater than 10.8 to 11.3 mg/dL and Ca[2+] level exceeding 1.4 mmol/L (depending on the norms of the analytical laboratory). In the neonate, hypercalcemia is most often manifested by lethargy or irritability, respiratory distress, anorexia, poor weight gain, constipation, and hypotonia. In the older child/adolescent, hypercalcemia may be clinically silent until development of changes in personality, recalcitrant constipation, renal calculi, or long bone fracture through a bone cyst, depending on the pathogenesis of the disorder. Causes of hypercalcemia in infancy and childhood are listed in **Table 535-3** , and the evaluation, diagnosis, and management of specific disorders are discussed below. ## **TABLE 535-3 CAUSES OF HYPERCALCEMIA**  "
},
{
"source": "Cover, p. 8198",
"text": "## **HYPOCALCEMIA** Hypocalcemia is due to either too little calcium entering the circulation from the gastrointestinal tract, bone, or kidney or excessive loss of calcium into urine, stool, or bone. Symptoms and signs of hypocalcemia in the neonate include hypotonia, respiratory distress, anorexia, jitteriness, tetany, and seizures. In the older child, hypocalcemia may be asymptomatic or manifested by irritability or lethargy, muscular twitching, tremulousness, anorexia, and seizures. The causes of hypocalcemia are listed in **Table 535-1** . ## **TABLE 535-1 CAUSES OF HYPOCALCEMIA**  "
},
{
"source": "CURRENT Diagnosis and Treatment Pediatrics, Twenty-Fourth Edition, p. 1068",
"text": "Shaw N: A practical approach to hypocalcaemia in children [Review]. Endocr Dev 2009;16:73\u201392 [PMID: 19494662]. ## **HYPERCALCEMIC STATES** Hypercalcemia is defined as a serum calcium level greater than 11 mg/dL. Severe hypercalcemia is a level greater than 13.5 mg/dL. ## ESSENTIALS OF DIAGNOSIS & TYPICAL FEATURES - \u00bb Abdominal pain, polyuria, polydipsia, hypertension, nephrocalcinosis, failure to thrive, renal stones, intractable peptic ulcer, constipation, uremia, and pancreatitis. - \u00bb Bone pain or pathologic fractures, subperiosteal bone resorption, renal parenchymal calcification or stones, and osteitis fibrosa cystica. - \u00bb Impaired concentration, altered mental status, mood swings, and coma. ## \u00bb **General Considerations** More than 80% of hypercalcemic children or adolescents have either hyperparathyroidism or a malignant tumor. Table 34\u20137 summarizes the differential diagnosis of childhood hypercalcemia (McNeilly, 2016)."
},
{
"source": "Zitelli and Davis' Atlas of Pediatric Physical Diagnosis: Expert Consult - Online, p. 408",
"text": " **----- Start of picture text -----**
Hypocalcemia
History
Newborn
Maternal hypercalcemia
Signs or symptoms of rickets
Normal Albumin Low
Phosphate Low iCa Normal
Factitious
Normal/Low Increased
hypocalcemia
Parathyroid
25(OH)\u2013D hormone High
Parathyroid
Low Normal hormone resistance
Low/Normal Magnesium deficiency
Vitamin D 1,25(OH)2\u2013D
Primary
deficiency
hypoparathyroidism
Low High
1\u03b1-Hydroxylase Vitamin D
deficiency resistance
**----- End of picture text -----**
**Figure 9-23** Hypocalcemia. Initial approach to the child with hypocalcemia."
},
{
"source": "MedStudy Pediatrics Core 11th Edition 2024-2025, p. 630",
"text": "Neonatal hypocalcemia is divided into early onset (prior to 72 hours of life) and late onset (after 72 hours of life). Early-onset hypocalcemia is primarily a transient prob- lem related to issues with birth and pregnancy and is not due to hypoparathyroidism. The most common cause of early-onset hypocalcemia is prematurity. Other causes include maternal illness (e.g., diabetes mellitus [DM], toxemia, hyperparathyroidism, antiseizure medication) and infant issues (e.g., sepsis, intrauterine growth restric- tion, asphyxia, hypomagnesemia, respiratory distress syndrome). [ [+ PTH, +1,25-(0H),-D] y Calcium oa \\ |+1,25-(OH),-D| [+ PTH, +1,25-(OH),-D| \u00a9 2023 MedStudy\u2014Please Report Copyright Infringements to copyright@medstudy.com"
},
{
"source": "Cover, p. 865",
"text": "## **DISORDERS OF CALCIUM REGULATION** ## **HYPOCALCEMIA** ## **DEFINITION** Neonatal hypocalcemia is generally defined as a serum total calcium concentration of less than 2 mmol/L (< 8 mg/dL) in term infants and less than 1.75 mmol/L (< 7 mg/dL) in preterm infants or an ionized calcium concentration of less than 0.75 to 1.1 mmol/L (< 3.0\u20134.4 mg/dL). Early-onset neonatal hypocalcemia typically is transient and occurs during the first 24 to 48 hours after birth; later-onset hypocalcemia usually occurs after the first week of life and commonly involves lasting pathology. ## **ETIOLOGY**"
},
{
"source": "Gomella's Neonatology: Management, Procedures, On-Call Problems, Diseases, and Drugs, Eighth Edition, p. 867",
"text": "- **B. Incidence.** Hypocalcemia is likely the most common disorder of either Ca[2+] or Mg[2+] in newborn infants, and it affects both preterm and term infants. It occurs in up to 30% of infants with birthweight <1500 g. Late-onset hypocalcemia is more common in developing countries where cow\u2019s milk or formulas with phosphate concentrations are used. - **C. Pathophysiology.** iCa[2+] is the biologically important form of calcium. The tCa[2+] levels have been repeatedly shown to not be predictive of iCa[2+] levels. Therefore, tCa[2+] levels are unreliable as criteria for true hypocalcemia. In premature infants, it has been shown that tCa[2+] levels as low as \u22646 mg/dL correspond to iCa[2+] levels >3 mg/dL. ## **D. Risk factors**"
},
{
"source": "Gomella's Neonatology: Management, Procedures, On-Call Problems, Diseases, and Drugs, Eighth Edition, p. 870",
"text": "- **b. Secondary.** Due to maternal hypoparathyroidism. **2. Maternal hypocalcemia** **3. Subcutaneous fat necrosis** **4. Therapeutic hypothermia** **5. Idiopathic infantile hypercalcemia** **6. Williams syndrome** **7. Hypophosphatasia** **8. Hyper- or hypothyroidism**  **9. Malignancy (very rare in the newborn)** **10. Distal renal tubular acidosis, Jansen metaphyseal chondrodysplasia** ## **11. Iatrogenic** - **a.** Hypophosphatemia due to inadequate dietary intake of phosphorus, especially in preterm infants - **b.** Excessive vitamin D intake - **c.** Excessive calcium intake - **d.** Thiazide diuretics - **e.** Extracorporeal life support - **E. Clinical presentation.** Mostly hypercalcemia is asymptomatic unless severe hypercalcemic levels have been reached and signs as described below appear. **1.** Feeding intolerance, constipation, failure to thrive **2.** Polyuria, dehydration"
},
{
"source": "MedStudy Pediatrics Core 11th Edition 2024-2025, p. 553",
"text": "[Figure OCR, page 553, figure 1] elevation. Decreased kidney function can occur in addi- tion to nausea, anorexia, and constipation. Other causes of hypercalcemia include leukemia, thyrotoxicosis, hyper- vitaminosis A, sarcoidosis, tuberculosis, subcutaneous fat necrosis, and primary hyperparathyroidism. Most patients with significant hypercalcemia are volume depleted and need NS replacement fluid. Calcitonin and bisphosphates are standard of care for persistent hypercalcemia. Loop diuretics are rarely used to treat hypercalcemia in children, unless overt volume overload develops. Hypocalcemia Hypocalcemia has multiple causes, of which the most common are: * Severe vitamin D deficiency * Chronic kidney disease\u2014results in secondary hyper- parathyroidism triggered by reduced serum Ca\u00ae* levels, which result from hyperphosphatemia and decreased renal conversion of 25-OH vitamin D to the active 1,25-(OH),-D * Severe pancreatitis * Rhabdomyolysis * Hypermagnesemia (Always check the Mg\u201d* level!)"
},
{
"source": "CURRENT Diagnosis and Treatment Pediatrics, Twenty-Fourth Edition, p. 98",
"text": "Hypocalcemia tends to occur at two different times in the neonatal period. Early-onset hypocalcemia occurs in the first 2 days of life and has been associated with prematurity, maternal diabetes, asphyxia, and rarely, maternal hypoparathyroidism. Late-onset hypocalcemia occurs at approximately 7\u201310 days and is observed in infants receiving modified cow\u2019s milk rather than infant formula (high phosphorus intake), in infants with hypoparathyroidism (DiGeorge syndrome, 22q11 deletion), or in infants born to mothers with severe vitamin D deficiency. Hypomagnesemia should be sought and treated in cases of hypocalcemia that are resistant to treatment. ## \u00bb **Treatment** ## **A. Oral Calcium Therapy** The oral administration of calcium salts, often along with vitamin D, is the preferred method of treatment for chronic forms of hypocalcemia resulting from hypoparathyroidism. (See Chapter 34.) ## **B. Intravenous Calcium Therapy** ## **HYPOCALCEMIA** ## ESSENTIALS OF DIAGNOSIS & TYPICAL FEATURES"
},
{
"source": "CURRENT Diagnosis and Treatment Pediatrics, Twenty-Fourth Edition, p. 98",
"text": "## **HYPOCALCEMIA** ## ESSENTIALS OF DIAGNOSIS & TYPICAL FEATURES - \u00bb Irritability, jitteriness, seizures (see also Chapter 34). - \u00bb Normal blood glucose. - \u00bb Possible dysmorphic features, congenital heart disease (DiGeorge syndrome). Calcium concentration in the immediate newborn period decreases in all infants. The concentration in fetal plasma is higher than that of the neonate or adult. Hypocalcemia is usually defined as a total serum concentration less than 7 mg/dL (equivalent to a calcium activity of 3.5 mEq/L), although the physiologically active fraction, ionized calcium, should be measured whenever possible, and is usually normal even when total calcium is as low as 6\u20137 mg/dL. An ionized"
},
{
"source": "Gomella's Neonatology: Management, Procedures, On-Call Problems, Diseases, and Drugs, Eighth Edition, p. 866",
"text": "## **91** Calcium Disorders (Hypocalcemia, Hypercalcemia) Abnormalities of calcium (Ca[2+] ) and magnesium (Mg[2+] ) metabolism are not infrequent occurrences among infants admitted for neonatal intensive care. Moreover, the disturbances of Ca[2+] may be mirrored by Mg[2+] , or conversely, as in hypocalcemia and hypomagnesemia. Infants of diabetic mothers (IDMs) and infants with fetal growth restriction (FGR) may present with low serum levels of either Ca[2+] or Mg[2+] or both. Serum values for Ca[2+] and Mg[2+] above or below accepted normal values are of concern in any infant and warrant further clinical studies. Magnesium disorders are discussed in Chapter 105. - **I. Hypocalcemia** - **A. Definition.** Hypocalcemia is determined by either **total serum calcium (tCa) or ionized calcium (iCa) values.** Clinical chemistry values for serum levels vary by units (ie, mEq/L, mmol/L, or mg/dL), by gestational age, and by day of age following DISEASES AND DISORDERS, GENERAL 834"
},
{
"source": "Ghai Essential Pediatrics, 9e (Vinod K Paul, Arvind Bagga), p. 523",
"text": "develop hypocalcemia during periods of rapid bone growth (4-8 weeks of life). Vitamin D-dependent rickets presents with early onset severe hypocalcemia and rickets. Increased chelation: Increased calcium binding results in reduction of ionic calcium and features of hypocalcemia. This is most commonly related to high phosphate levels (renal failure or release of intracellular phosphate due to hemolysis, tumor lysis or rhabdomyolysis). Increased phosphate levels in cow milk and commercial formula is an important cause of neonatal hypocalcemia. Metabolic or respiratory alkalosis increases albumin binding of calcium resulting in hypocalcemia. Evaluation Evaluation is directed towards identification of etiology and assessment of the severity of illness. Clinical: Detailed history of the age of onset, presenting features, frequency of episodes of hypocalcemia and family history should be obtained. Neonates should be screened for prematurity, birth asphyxia, maternal hyperparathyroidism and initiation of top feeds."
},
{
"source": "Kliegman R. Nelson Textbook of Pediatrics 2-Volume Set 22ed 2024, p. 1067",
"text": "## **121.4** Hypocalcemia ## _Kathleen A. Gibbs and Eric C. Eichenwald_ Hypocalcemia in a neonate can manifest as irritability, jitteriness, clonus, or seizures. Electrocardiography can show a prolonged QT interval. The cause may simply represent an exaggerated physiologic decrease in serum calcium levels within the first 24 hours of life or pathologic conditions such as genetic disorders (22q deletions), prematurity, growth restriction, perinatal hypoxia, hypomagnesemia, or maternal diabetes. Hypocalcemia is more common in term infants receiving formula than in those exclusively receiving breast milk. Most infants remain asymptomatic and can be managed conservatively with early nutrition and close monitoring, whereas symptomatic neonates should receive intravenous or oral calcium replacement. _Visit Elsevier eBooks+ at eBooks.Health.Elsevier.com for Bibliography._ ## **121.5** Hypermagnesemia ## _Kathleen A. Gibbs and Eric C. Eichenwald_"
}
]
}