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

PURPOSE: To review clinical symptoms, laboratory findings, and treatment of transient neonatal hypocalcemia. METHODS: Medical records of full-term (gestational age ≥37 weeks) neonates diagnosed with hypocalcemia, aged 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.

Clinical Characteristics of Acute Respiratory Tract Infections in Full-Term Newborns without Risk Factors

PURPOSE: This study evaluated the characteristics and symptoms of full-term newborns without risk factors who were diagnosed with acute lower respiratory tract infections (ALRI). METHODS: Nasopharyngeal aspirates were obtained from 72 full-term newborns to 30 days of age who were diagnosed with ALRI from September 2011 to November 2013 and analyzed by multiplex real time-polymerase chain reaction (RT-PCR). RESULTS: Viruses were detected in 60 newborns (83.3%). Single viruses were observed in 56 newborns (77.7%). The most commonly detected viral agent was respiratory syncytial virus (RSV) (63.8%), followed by parainfluenza virus (6.9%), rhinovirus A/B (4.1%), and human coronavirus (2.7%). Clinical diagnoses of ALRI in newborns with a single virus included pneumonia (66.07%), bronchiolitis (30.43%), bronchitis (5.35 %), and croup (1.79%). There were no differences in epidemiological characteristics between RSV and other viruses. However, newborns diagnosed with RSV had prolonged hospitalizations and significantly increased respiratory rates. CONCLUSION: Respiratory viruses, especially RSV, are pivotal causes of ALRI in newborns. Further, studies on RSV severity and vaccination are necessary to reduce hospitalization and mortality of full-term infants.

A Novel MUT Gene Mutation Detected in a Female Infant with Methylmalonic Acidemia

Methylmalonic acidemia (MMA) is an autosomal recessive metabolic disease. MMA results from a deficiency of L-methylmalonyl-CoA mutase (encoded by MUT), its cofactor 5-deoxyadenosylcobalamin (MMAA, MMAB, and MMADHC), or a deficiency of methylmalonyl CoA-epimerase (MCEE). We report the case of a 5-day-old infant with MMA in which a missense and a novel nonsense mutation in MUT were present. Direct sequencing analysis of MUT revealed a heterozygous c.1106G>A (p.Arg369His) mutation in exon 6 and a heterozygous c.362_368dupAGTTCTA (p.Tyr123*) mutation in exon 2; the latter results in a premature stop codon.