Pseudoparalysis in Infantile Vitamin B12 Deficiency.

The neurocutaneous syndrome of infantile B12 deficiency, also called the "infantile tremor syndrome," is reported mainly from India. Typically, the child of a vegetarian mother who breastfeeds presents with developmental delay, regression of milestones, and tremors. The baby typically appears chubby, has sparse hypopigmented hair, and hyperpigmentation on the dorsum of the hands, feet, and other parts of the body. We share our observations in five children with akinesis and the typical features of severe infantile vitamin B12 deficiency. After initiating therapy with injectable vitamin B12, the children showed rapid recovery of movements in the first two weeks. The recovery went through a phase of generalized rigidity in two children. We postulate that the state of akinesis, or pseudoparalysis, is secondary to energy depletion of the basal ganglia. The basal ganglia, one of the regions with high metabolic rates, appear to be selectively vulnerable to vitamin B12 deficiency.