Serum 25-hydroxyvitamin D in infantile rickets

Area of Science:

• Pediatric Endocrinology
• Nutritional Biochemistry
• Metabolic Bone Disease

Background:

• Nutritional vitamin D deficiency is a common concern in pediatric populations.
• 25-hydroxyvitamin D (25-OH-D) is the primary indicator of vitamin D status.
• Understanding 25-OH-D dynamics is crucial for managing deficiency-related conditions.

Purpose of the Study:

• To correlate serum 25-hydroxyvitamin D concentrations with the clinical stages of nutritional vitamin D deficiency in children.
• To investigate 25-OH-D levels in children with familial hypophosphatemia.
• To explore the potential role of parathyroid hormone in 25-OH-D depletion.

Main Methods:

• Serum 25-OH-D levels were measured in pediatric patients.
• Clinical disease staging was performed for nutritional vitamin D deficiency.
• Comparison of 25-OH-D levels between deficient children, familial hypophosphatemia patients, and healthy controls.

Main Results:

• Serum 25-OH-D was low but within normal limits in the early hypocalcemic stage of deficiency (16-20 ng/ml).
• 25-OH-D levels decreased further (<15 ng/ml) in advanced stages of vitamin D deficiency.
• Children with familial hypophosphatemia exhibited normal serum 25-OH-D concentrations, similar to controls.

Conclusions:

• Serum 25-OH-D concentration is a valuable biomarker that reflects the severity of nutritional vitamin D deficiency in children.
• Familial hypophosphatemia appears to have a different pathophysiology regarding vitamin D metabolism compared to nutritional deficiency.
• Endogenous parathyroid hormone may contribute to the reduction of serum 25-OH-D in deficiency states.