Formula fed twin infants with recurrent hypocalcemic seizures with vitamin D deficient rickets and hyperphosphatemia

Bacteremia in a Newborn with Hypocalcemic Seizures and Vitamin D Deficiency

Infants with neonatal hypocalcemia often present with seizures, and neonatal hypocalcemia can be due to parathyroid (PTH) insufficiency or resistance. Causes of hypocalcemia with PTH elevation include increased phosphate load, vitamin D deficiency (VDD) or defects in metabolism, renal dysfunction, hypomagnesemia, genetic mutations resulting in end-organ resistance to PTH, or critical illness. Hypocalcemia has also been shown to be associated with Gram-negative bacteremia and sepsis in adults. We present the case of a full-term, formula-fed newborn presenting with late-onset hypocalcemic seizures and VDD in the setting of Klebsiella pneumoniae bacteremia. This case highlights that newborns presenting with hypocalcemic seizures should undergo a workup for sepsis.

Vitamin D deficiency associated with dilated cardiomyopathy in early infancy caused by maternal cholestasis

Breast feeding is known to be a major cause of vitamin D deficiency in infants because the content of vitamin D in breast milk is significantly lower than that in formula. We report a case of a 1-mo-old boy who developed hypocalcemic seizures and dilated cardiomyopathy caused by vitamin D deficiency despite being fed a sufficient amount of regular formula. The cause of vitamin D deficiency in this case was maternal vitamin deficiency due to severe hyperemesis and insufficient sunlight exposure, induced mainly by the malabsorption of fat-soluble vitamins caused by maternal cholestasis. We should carefully consider maternal conditions during pregnancy and the postpartum period to detect and prevent vitamin D deficiency in the fetus and infant.