Treatment of Vitamin D Deficiency in Pediatric Patients
The treatment of vitamin D deficiency in pediatric patients should follow a structured dosing regimen based on the severity of deficiency, with supplementation doses ranging from 2,000-8,000 IU daily or 50,000 IU weekly depending on serum 25(OH)D levels. 1
Diagnosis and Classification
Before initiating treatment, it's important to establish the diagnosis through measurement of serum 25-hydroxyvitamin D [25(OH)D] levels:
- Severe deficiency: <5 ng/mL (12 nmol/L)
- Mild deficiency: 5-15 ng/mL
- Insufficiency: 16-30 ng/mL
- Target level: ≥30 ng/mL (75 nmol/L) 2, 1
Treatment Protocol
Dosing Regimen Based on Severity
| Serum 25(OH)D Level | Classification | Recommended Supplementation | Duration |
|---|---|---|---|
| <5 ng/mL | Severe deficiency | 8,000 IU/day or 50,000 IU weekly | 4 weeks, then 4,000 IU/day for 2 months |
| 5-15 ng/mL | Mild deficiency | 4,000 IU/day or 50,000 IU every other week | 12 weeks |
| 16-30 ng/mL | Insufficiency | 2,000 IU/day or 50,000 IU every 4 weeks | 12 weeks |
Maintenance Therapy
After achieving normal levels (>30 ng/mL), continue with:
- Infants and children: 400-1,000 IU daily 3
- Yearly monitoring of serum 25(OH)D levels during maintenance therapy 1
Form of Vitamin D
Both vitamin D2 (ergocalciferol) and vitamin D3 (cholecalciferol) are effective in treating vitamin D deficiency in children:
- Research shows that short-term vitamin D2 2,000 IU daily, vitamin D2 50,000 IU weekly, or vitamin D3 2,000 IU daily yield equivalent outcomes in treating hypovitaminosis D among young children 4
- However, cholecalciferol (D3) appears to have higher bioefficacy than ergocalciferol (D2), although long-term comparative trials in children are lacking 2
Special Considerations
Calcium Supplementation
- Consider calcium supplementation (250-500 mg/day) in patients with low ionized calcium and/or elevated PTH levels 2
- Monitor ionized calcium, 25-OH-D3, and PTH levels closely during treatment 2
High-Risk Populations
Children with chronic kidney disease (CKD): Have a high prevalence (80-90%) of vitamin D insufficiency due to:
- Sedentary lifestyle with reduced sun exposure
- Limited intake of vitamin D-rich foods
- Reduced endogenous synthesis with uremia
- Urinary losses of 25(OH)D in nephrotic patients 2
Children with malabsorption: Consider calcifediol (25-hydroxyvitamin D3) as it has better absorption in patients with fat malabsorption 5
Administration Routes
- Oral/enteral route is preferred for most patients
- Parenteral administration (IM) may be necessary for patients not responsive to oral supplementation, though it's more complicated and may be contraindicated in patients with anticoagulation or infection risk 2
Monitoring
- Measure serum 25(OH)D levels after 3-6 months of treatment to ensure adequate dosing 2
- Monitor for signs of toxicity, especially with high doses:
- Hypercalcemia
- Hypercalciuria
- Kidney stones
Common Pitfalls to Avoid
Inadequate dosing: Standard doses within the recommended daily allowance take many weeks to normalize low vitamin D levels. When rapid correction is needed, a loading dose is necessary 2
Using single large annual doses: Not recommended as it has been associated with increased risk of fractures and falls 1
Failure to supplement calcium: Vitamin D supplementation alone may be insufficient if calcium intake is inadequate 2
Overlooking individual factors: Factors like obesity, skin pigmentation, or medication use may affect vitamin D requirements and should be considered when determining dosage 1
Neglecting nutritional aspects: Ensure adequate dietary intake of vitamin D-rich foods (cod liver oil, fish, liver, egg yolk, fortified milk) alongside supplementation 2