In a very low birth weight (VLBW) neonate on parenteral nutrition, the serum alkaline phosphatase is 1800 U/L, phosphorus is 1.2 mg/dL, and the chest X-ray shows generalized bone demineralization with cupping of distal radius. Which supplementation is MOST critical to prevent progression?

• A Vitamin D 2000 IU daily
• B Phosphorus supplementation (primary deficiency in preterm) ✓
• C High-dose calcium supplementation alone
• D Vitamin K supplementation

Explanation

Metabolic bone disease (osteopenia) of prematurity in VLBW neonates is primarily due to phosphorus deficiency, not calcium or vitamin D deficiency. Preterm infants miss the third-trimester mineral accretion when 80% of bone mineralization occurs. The low phosphorus, elevated alkaline phosphatase, and radiographic findings confirm phosphopenic rickets of prematurity. Phosphorus supplementation is the primary treatment; calcium and vitamin D are also needed but phosphorus is the rate-limiting nutrient.

Reference: Ghai Essential Pediatrics, 10th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.