Vitamin B12 Deficiency in Infants

Vitamin B12 is a water-soluble vitamin with essential cellular functions. The main sources for humans are foods of animal origin. Vitamin B12 deficiency is more common in childhood than previously recognised. Clinical symptoms in children are often non-specific and may include megaloblastic anaemia, failure to thrive, muscle hypotonia, irritability or lethargy. Risk factors include families of low socio-economic status, exclusively breastfed infants of vegetarian mothers, and conditions leading to malabsorption. The authors present a clinical case of a 13-month-old child with malnutrition and vitamin B12 deficiency resulting in megaloblastic anaemia and neurological involvement manifested by apathy and lethargy.