[Severe encephalopathy and vitamin B12 deficiency: reversibility after nutritional therapy]

Area of Science:

• Neurology
• Pediatrics
• Nutritional Science

Background:

• Vitamin B12 (cobalamin) is vital for central nervous system (CNS) function, hematopoiesis, and DNA synthesis.
• Deficiency often arises from pernicious anemia or strict vegetarian diets, impacting neurological and developmental processes.
• Infants, particularly those breastfed by mothers with inadequate B12 intake, are at risk.

Observation:

• An 18-month-old male infant presented with acute altered consciousness and movement disorder (tremor, choreiform movements).
• He exhibited delayed motor milestones and progressive loss of acquired skills.
• Neuroimaging revealed generalized supratentorial atrophy and basal ganglia involvement.

Findings:

• The infant's family followed a vegetarian diet, and he was breastfed.
• Intramuscular vitamin B12 supplementation rapidly increased serum levels.
• Clinical and radiological normalization occurred within 6-7 months following supplementation and dietary changes.

Implications:

• Highlights the critical need for maternal vitamin B12 status assessment during pregnancy and lactation in vegetarian families.
• Underscores the potential for severe, reversible neurological damage from vitamin B12 deficiency in infants.
• Emphasizes prompt diagnosis and intervention for optimal neurodevelopmental outcomes.