Ann Pediatr Endocrinol Metab.  2015 Jun;20(2):86-91. 10.6065/apem.2015.20.2.86.

Clinical and laboratory characteristics of neonatal hypocalcemia

Affiliations
  • 1Department of Pediatrics, Seoul National University Children's Hospital, Seoul National University College of Medicine, Seoul, Korea.
  • 2Division of Endocrinology and Metabolism, Department of Pediatrics, Seoul National University Bundang Hospital, Seongnam, Korea. chyerim@hanmail.net

Abstract

PURPOSE
To describe the clinical characteristics of full-term neonates with hypocalcemia and to suggest factors associated with neonatal hypocalcemia
METHODS
The medical records of full-term neonates with hypocalcemia were reviewed. Hypocalcemia was defined as an ionized calcium (iCa) concentration of <4 mg/dL. Parathyroid hormone (PTH) insufficiency was defined as a serum PTH level of <60 pg/mL or a serum phosphorus level higher than the serum calcium level in the presence of hypocalcemia.
RESULTS
Fifty-three neonates were enrolled. The median age at diagnosis of hypocalcemia was 3 days. In all the neonates, formula feeding predominance was observed. Thirty-eight neonates (69.8%) were compatible with PTH insufficiency. The number of formula-fed neonates was significantly higher than that of breast-fed patients among neonates with PTH insufficiency (P=0.017). Intact PTH was negatively correlated with serum phosphorus levels. Twelve out of 14 neonates (85.7%) had 25-hydroxy vitamin D (25OHD) levels <20 ng/mL and 9 neonates (64.3%) had 25OHD levels <10 ng/mL. Twenty-one neonates had hypocalcemic tetany. The serum calcium and iCa concentrations of neonates with tetany were 4.2-8.3 mg/dL and 1.85-3.88 mg/dL, respectively. Three neonates showed symptomatic hypocalcemia with calcium levels over 7.5 mg/dL. Among the 16 neonates who underwent electroencephalography (EEG), 12 had abnormalities, which normalized after 1-2 months.
CONCLUSION
Formula milk feeding, PTH insufficiency and low serum vitamin D concentration are associated with the development of neonatal hypocalcemia. Symptoms such as tetany and QT interval prolongation can develop in relatively mild hypocalcemia. Moreover, transient neonatal hypocalcemia can cause transient EEG abnormalities.

Keyword

Hypocalcemia; Newborn infant; Parathyroid hormone; Tetany

MeSH Terms

Calcium
Diagnosis
Electroencephalography
Humans
Hypocalcemia*
Infant, Newborn
Medical Records
Milk
Parathyroid Hormone
Phosphorus
Tetany
Vitamin D
Calcium
Parathyroid Hormone
Phosphorus
Vitamin D

Reference

1. Gertner JM. Disorders of calcium and phosphorus homeostasis. Pediatr Clin North Am. 1990; 37:1441–1465. PMID: 2259548.
Article
2. Loughead JL, Mimouni F, Tsang RC. Serum ionized calcium concentrations in normal neonates. Am J Dis Child. 1988; 142:516–518. PMID: 3358391.
Article
3. Kovacs CS, Lanske B, Hunzelman JL, Guo J, Karaplis AC, Kronenberg HM. Parathyroid hormone-related peptide (PTHrP) regulates fetal-placental calcium transport through a receptor distinct from the PTH/PTHrP receptor. Proc Natl Acad Sci U S A. 1996; 93:15233–15238. PMID: 8986793.
Article
4. Thomas TC, Smith JM, White PC, Adhikari S. Transient neonatal hypocalcemia: presentation and outcomes. Pediatrics. 2012; 129:e1461–e1467. PMID: 22614771.
Article
5. Naylor KE, Iqbal P, Fledelius C, Fraser RB, Eastell R. The effect of pregnancy on bone density and bone turnover. J Bone Miner Res. 2000; 15:129–137. PMID: 10646122.
Article
6. Hsu SC, Levine MA. Perinatal calcium metabolism: physiology and pathophysiology. Semin Neonatol. 2004; 9:23–36. PMID: 15013473.
Article
7. Tsang RC, Chen IW, Friedman MA, Chen I. Neonatal parathyroid function: role of gestational age and postnatal age. J Pediatr. 1973; 83:728–738. PMID: 4795442.
Article
8. Kim HS. Calcium and phosphate metabolism and disorders in the newborn. Korean J Pediatr. 2007; 50:230–235.
Article
9. Venkataraman PS, Tsang RC, Greer FR, Noguchi A, Laskarzewski P, Steichen JJ. Late infantile tetany and secondary hyperparathyroidism in infants fed humanized cow milk formula. Longitudinal follow-up. Am J Dis Child. 1985; 139:664–668. PMID: 3874538.
Article
10. Fomon SJ, Nelson SE. Calcium, phosphorus, magnesium, and sulfur. In : Fomon SJ, editor. Nutrition of normal infants. St. Louis: Mosby-Year Book;1993. p. 192–216.
11. Abrams SA, Griffin IJ, Davila PM. Calcium and zinc absorption from lactose-containing and lactose-free infant formulas. Am J Clin Nutr. 2002; 76:442–446. PMID: 12145020.
Article
12. Ross AC, Taylor CL, Yaktine AL, Del Valle HB, editors. Committee to Review Dietary Reference Intakes for Vitamin D and Calcium. Institute of Medicine. Dietary reference intakes for calcium and vitamin D. Washington, DC: National Academies Press;2011.
13. Abrams SA. Calcium absorption in infants and small children: methods of determination and recent findings. Nutrients. 2010; 2:474–480. PMID: 22254034.
Article
14. Standing Committee on the Scientific Evaluation of Dietary Reference Intakes. Food and Nutrition Board. Institute of Medicine. Dietary reference intakes for Calcium, Phosphorus, Magnesium, Vitamin D, and Fluoride. Washington, DC: National Academies Press;1997.
15. Okonofua F, Menon RK, Houlder S, Thomas M, Robinson D, O'Brien S , et al. Parathyroid hormone and neonatal calcium homeostasis: evidence for secondary hyperparathyroidism in the Asian neonate. Metabolism. 1986; 35:803–806. PMID: 3747837.
Article
16. Newman DB, Fidahussein SS, Kashiwagi DT, Kennel KA, Kashani KB, Wang Z, et al. Reversible cardiac dysfunction associated with hypocalcemia: a systematic review and meta-analysis of individual patient data. Heart Fail Rev. 2014; 19:199–205. PMID: 23355181.
Article
17. Nekvasil R, Stejskal J, Tuma A. Detection of early onset neonatal hypocalcaemia in low birth weight infants by Q-Tc and Q-oTc interval measurement. Acta Paediatr Acad Sci Hung. 1980; 21:203–210. PMID: 7282350.
18. Lynch BJ, Rust RS. Natural history and outcome of neonatal hypocalcemic and hypomagnesemic seizures. Pediatr Neurol. 1994; 11:23–27. PMID: 7986288.
Article
19. Sankar JM, Agarwal R, Deorari A, Paul VK. Management of neonatal seizures. Indian J Pediatr. 2010; 77:1129–1135. PMID: 20882435.
Article
20. Song JY, Shin YL, Yoo HW. Clinical characteristics of symptomatic hypocalcemic infants. J Korean Soc Pediatr Endocrinol. 2002; 7:95–104.
21. Sperling MA. Pediatric endocrinology. 4th ed. Philadelphia: WB Saunders Co.;2014. p. 734.
Full Text Links
  • APEM
Actions
Cited
CITED
export Copy
Close
Share
  • Twitter
  • Facebook
Similar articles
Copyright © 2024 by Korean Association of Medical Journal Editors. All rights reserved.     E-mail: koreamed@kamje.or.kr