Causes and Clinical Features of Transient Hypocalcemia in Newborn: A Single Center Study

Song, Byung Jin; Kim, Hae Sook; Kim, Won Duck

Abstract

PURPOSE
To review clinical symptoms, laboratory findings, and treatment of transient neonatal hypocalcemia.
METHODS
Medical records of full-term (gestational age â‰¥37 weeks) neonates diagnosed with hypocalcemia, aged <31 days, were investigated retrospectively. Using a cut-off of 3 days after birth, cases of neonatal hypocalcemia were classified as early or late. Hypocalcemia was defined as ionized calcium level <4 mg/dL or serum calcium level <7.5 mg/dL. Hyperphosphatemia was defined as serum phosphate level >8 mg/dL. Relative hypoparathyroidism was defined as hypocalcemia and hyperphosphatemia with parathyroid hormone level within the normal range (10-65 pg/mL).
RESULTS
Of 68 included neonates, 62 were diagnosed with hypoparathyroidism with hypocalcemia and hyperphosphatemia, and 26 had seizures. Mean serum calcium level of the seizure group was 5.99 mg/dL, which was significantly lower than that of the non-seizure group (6.46 mg/dL, P=0.012). The recovery duration for calcium and phosphate levels was long, at 5.8 and 10.7 days, respectively. The calcium level recovery duration was significantly different between the seizure and non-seizure groups (P=0.034), but the phosphate level recovery period was not significantly different (P=0.194). Of 17 patients with diarrhea, 10 had confirmed rotavirus infection. Most patients with hypocalcemia responded well to oral calcium lactate and intravenous calcium gluconate, and the treatments could be discontinued after a certain period.
CONCLUSION
Transient neonatal hypocalcemia is associated with hypoparathyroidism. The major symptom in late neonatal hypocalcemia was the occurrence of seizures. Serum calcium level was lower and the recovery period was longer in the seizure group, but most cases exhibited favorable progress.