In view of the unique bone mineral requirements of preterm infants, the American Academy of Pediatrics (AAP)published guidance for healthcare professionals to evaluate and manage preterm infants.
Summary of AAPguidance:
Preterm infants at high-risk of rickets
- < 27 weeks’ gestation or birth weight < 1,000 g with a history of multiple medical problems.
Routine evaluation of bone mineral status
- Biochemical testing, e.g. serum alkaline phosphatase activity (APA) should be indicated for infants with birth weight < 1,500 g, and started 4 to 5 weeks after birth.
Radiographic evaluation for rickets
- Should be indicated for infants with serum APA > 800 to 1,000 IU/L or clinical evidence of fractures.
- Should be considered given to infants with a persistent phosphorus concentration of less than ~4.0 mg/dL.
Use of human milk fortified with minerals / formulas designed for preterm infants
- Should be followed for infants with birth weight < 1,800 to 2,000 g:
Calcium, mg/kg per day Phosphorus, mg/kg per day Vitamin D, IU per day 150 - 220 75 - 140 200 - 400
Management after discharge from the hospital
- A follow-up serum APA at 2 to 4 weeks after discharge from the hospital may be considered for preterm infants who were exclusively breastfed.
Vitamin D intakes for infants reach a body weight > 1,500 g and tolerate full enteral feeds
- ~400 IU/day, and up to a maximum of 1,000 IU/day.
Abrams SA; Committee on Nutrition. Calcium and vitamin d requirements of enterally fed preterm infants. Pediatrics. 2013 May;131(5):e1676-83. Link to PubMed