Healthy term babies undergo a physiological nadir in serum calcium levels by 24-48 hours of age. The nadir may be related to the delayed response of parathyroid and calcitonin hormones in a newborn. This nadir may drop to hypocalcemic levels in high-risk neonates including infants of diabetic mothers, preterm infants and infants with perinatal asphyxia. The early onset hypocalcemia which presen...

Ionized calcium in serum has been determined potentiometrically by using a calcium ion-selective electrode in a flow.through configuration. For 397 normal human adults the mean value for serum ionic calcium was 1.22 ± 0.09(2 SD) mmol/Iiter. Factors affecting the measurement-such as the pro. cedure for sample collection, sample storage, the preparation of standard solutions, the type of resin em...

BACKGROUND Many factors influence serum calcium concentration, but the major determinants of calcium homeostatsis are parathyroid hormone (PTH), vitamin D, the ionized calcium, and phosphate [1]. Therefore, deranged calcium metabolism is often seen in the presence of disordered parathyroid hormone (PTH) and/or vitamin D actions. Among these causes is end-organ resistance to the biological effec...