Treatment of Vitamin B12 Deficiency in Children Under 2 Years
For children under 2 years with vitamin B12 deficiency, the recommended treatment is 0.3 μg/kg/day of cobalamin for infants up to 12 months, with oral supplementation being effective and appropriate for most cases of nutritional deficiency. 1
Dosing Recommendations
Based on Age
- Infants up to 12 months: 0.3 μg/kg/day of cobalamin 1
- Children 1-2 years: Transitioning toward 1 μg/day (for older children) 1
Route of Administration
Oral Supplementation
- For nutritional deficiency: Oral cyanocobalamin has been proven effective in children 2, 3
- Dosing regimen for nutritional deficiency: 1000 μg daily for one week, then every other day for 2 weeks, then twice weekly for 2 weeks, followed by once weekly maintenance 3
Parenteral Administration (Intramuscular)
- Indications: Severe deficiency, malabsorption conditions, or neurological symptoms 4
- Initial dosing: 1000-2000 μg intramuscularly 5
- Advantage: Rapid absorption with peak plasma levels within 1 hour after injection 6
Treatment Considerations by Etiology
Nutritional Deficiency
- Common in exclusively breastfed infants of vegetarian/vegan mothers 4
- Treatment: Oral supplementation is effective 2, 3
- Prevention: Supplement pregnant and breastfeeding women on vegan diets 4
Malabsorption Conditions
- Includes ileal disease/resection, inflammatory bowel disease 5
- Treatment: Parenteral administration preferred 5, 7
- For ileal resection >20 cm: Lifelong B12 supplementation is mandatory 5
Monitoring and Follow-up
- Initial response: Abnormal movements may resolve within 1-2 days of treatment initiation 4
- Paradoxical reaction: Movement disorders may occasionally appear a few days after treatment initiation while neurological symptoms are improving 4
- Duration of monitoring: These movement disorders can last 2-6 weeks 4
- Laboratory monitoring: Check vitamin B12 levels at 1 month and 3 months after treatment initiation 2
Important Clinical Considerations
- Early treatment is crucial: Untreated vitamin B12 deficiency can cause permanent neurodevelopmental damage 4
- Symptoms in infants: Failure to thrive, lethargy, hypotonia, developmental regression, and sometimes megaloblastic anemia 4
- Response to treatment: Significant improvement in B12 levels can be expected after 1 month of appropriate therapy 2
- Age considerations: Younger children may respond better to the same dose compared to older children, suggesting weight-based dosing is important 3
Pitfalls to Avoid
- Delayed treatment: Vitamin B12 deficiency left untreated for more than 3 months may cause permanent degenerative lesions of the spinal cord 5
- Inadequate monitoring: Regular follow-up is essential to ensure normalization of B12 levels and resolution of symptoms
- Overlooking maternal status: For breastfed infants, maternal B12 status should be assessed and addressed
- Inappropriate route selection: For malabsorption conditions, oral therapy alone may be insufficient 7
Remember that prompt diagnosis and treatment are essential to prevent lasting neurodevelopmental damage in this vulnerable age group.