Relation between changes in plasma calcium in first week of life and renal function

Area of Science:

• Neonatal physiology
• Pediatric nutrition
• Renal function in infants

Background:

• Plasma calcium levels naturally fluctuate in newborns.
• Infant feeding methods can impact neonatal metabolic processes.

Purpose of the Study:

• To investigate the relationship between infant feeding type and plasma calcium levels.
• To explore the role of renal function markers in neonatal calcium homeostasis.

Main Methods:

• Comparison of plasma calcium, creatinine, and osmolality in breast-fed versus formula-fed infants.
• Analysis of creatinine and osmolar excretion in relation to plasma calcium changes.
• Observational study of 71 formula-fed and 35 breast-fed infants during the first week of life.

Main Results:

• 31 of 71 formula-fed infants showed a drop in plasma calcium, versus 5 of 35 breast-fed infants.
• Formula-fed infants with rising plasma calcium had lower creatinine and higher excretion than those with falling calcium.
• Formula-fed infants with rising calcium had lower plasma osmolality and higher urinary osmolar excretion.

Conclusions:

• Artificial feeding with cow's milk may be associated with a higher incidence of hypocalcemia in newborns.
• Delayed increase in glomerular filtration rate in some infants may cause phosphate retention, contributing to hypocalcemia.
• Renal function markers like creatinine and osmolality correlate with plasma calcium changes in artificially-fed neonates.