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Vitamin B12 deficiency: case report and review of literature
Brahim El Hasbaoui1, Nadia Mebrouk2, Salahiddine Saghir1
1Department of Pediatrics, Military Teaching Hospital Mohammed V, Faculty of Medicine and Pharmacy, University Mohammed V, Rabat, Morocco.
Insights
Vitamin B12 deficiency in infants can cause developmental delays and regression. Early diagnosis and treatment are crucial for preventing irreversible neurological damage, especially in breastfed infants of deficient mothers.
Area of Science:
- Pediatrics
- Neurology
- Nutritional Science
Background:
- Vitamin B12 deficiency is a significant cause of neurodevelopmental issues in young children.
- Exclusively breastfed infants of deficient mothers are particularly vulnerable.
Observation:
- Symptoms manifest between 2-12 months, including lethargy, hypotonia, and developmental regression.
- Abnormal movements like tremors and chorea occur in about half of affected infants.
- Elevated urinary methylmalonic acid and homocysteine levels are characteristic indicators.
Findings:
- Early diagnosis and prompt Vitamin B12 treatment rapidly correct metabolic abnormalities.
- Maternal Vitamin B12 supplementation during pregnancy can prevent infant neurological complications.
Implications:
- Awareness is critical for vegan and vegetarian mothers regarding risks of deficiency during pregnancy and lactation.
- Nutritional history assessment is vital for early prevention and management of Vitamin B12 deficiency in infants and mothers.
Abstract:
Vitamin B12 deficiency in early childhood is an important cause of neurodevelopmental delay and regression. Most of these cases occur in exclusively breast-fed infants of deficient mothers. Symptoms and signs of vitamin B12 deficiency appear between the ages of 2 to 12 months and include vomiting, lethargy, failure to thrive, hypotonia, and arrest or regression of developmental skills. Approximately one half of this cases exhibit abnormal movements, variously described as tremors, twitches, chorea, or myoclonus. Urinary concentrations of methylmalonic acid and homocysteine are characteristically elevated in vitamin B12 deficiency. Hyperglycinuria is sometimes present. The early diagnosis and treatment of vitamin B12 deficiency is crucial for significant neurological impairment and long-term prognosis. Treatment with vitamin B12 corrects these metabolic abnormalities very rapidly (within a few days). Vitamin B12 supplementation of pregnant women may prevent neurological and neuroradiological findings of the infants. Because of the importance of vitamin B12 in the development of the foetal and neonatal brain, vegetarian and vegan mothers should be aware of the severe and not fully-reversible damages caused by insufficient nutritional intake of vitamin B12 during pregnancy and lactation. Therefore, efforts should be directed to prevent its deficiency in pregnant and breastfeeding women on vegan diets and their infants. It is also important to take the nutritional history of both infants and their mothers for the early prevention and treatment. Here an interesting case of vitamin B12 deficiency in a 10-month-old boy presented with psychomotor regression, hypotonia and lethargy.
