Late-Onset Neonatal Hypocalcemia Due to Transient Hypoparathyroidism in Infant of Mother With COVID-19 at Delivery

Introduction: Neonatal hypocalcemia is an uncommon condition but clinical presentation can include severe manifestations such as neuromuscular irritability, tetany, seizure or cardiac conduction abnormalities that require prompt intervention to normalize calcium levels. To our knowledge there have been no reports of neonatal hypocalcemia following maternal SARS-CoV2 infection at the time of birth. Here we report a case of transient late-onset neonatal hypocalcemia complicated by maternal SARS-CoV-2 infection at the time of delivery. Clinical Case: A 13-day old full-term appropriate for gestational age female was born to an asymptomatic mother who tested positive for SARS-CoV2 at the time of delivery. Caretakers noticed minor twitching movements in the first few days of life that were progressively worsening. Initial ionized calcium was 0.6 mmol/L, and labs at time of transfer to our hospital were notable for total calcium of 5.5mg/dL(n 8.9–9.9), and ionized calcium of 0.67mmol/L (n 1.12–1.37 mmol/L). Calcium levels improved after she received IV calcium boluses and was started on continuous IV calcium infusion. Initial phosphorus was 8.3 mg/dL (n 3.2–7.4 mg/dL) and magnesium was 1.2 mg/dL (n 1.5–2.2 mg/dL), while intact PTH was inappropriately low at 12.2 pg/mL (n 10–65 pg/mL), and urine calcium to urine creatinine ratio was below the limits of assay detection (n <0.86), consistent with a diagnosis of neonatal hypoparathyroidism. The 25-hydroxy vitamin D was 11.1 ng/mL (n 30–100 ng/mL), which may have also been a contributing factor. She had no dysmorphic features on examination concerning for 22q deletion syndrome, and tested negative for SARS-CoV2. Chromosomal microarray did not reveal clinically relevant copy number alterations or areas of homozygosity. Calcium stabilized on enteral calcium carbonate, calcitriol, and cholecalciferol, and she was weaned off of all supplementation. Prior to discharge PTH recovered to 36.9 pg/ml with a calcium of 9.9 mg/dL, phosphorus 7.7 mg/dL, normal magnesium and 25-hydroxy vitamin D (31.3 ng/ml). She was discharged on Similac PM 60/40 formula to reduce her dietary phosphorus content, and 400 IU of cholecalciferol. Conclusions: Hypocalcemia in patients with severe COVID-19 is being increasingly reported. There is minimal data on the effect of perinatal SARS-CoV2 infections on neonatal health. While this report does not establish causation, expanding awareness of neonatal abnormalities following maternal SARS-CoV2 infection at delivery will help to recognize causal associations and improve patient care.