Nutritional nystagmus in infants.

Two infants presented with acquired infantile nystagmus. On examination, they manifested peculiar facies, growth and developmental delay, failure to thrive, and a Wernicke's type of nystagmus. Suspicion of a B vitamin deficiency resulted in correct diagnosis of dietary deficiency and/or enzymatic defect. In both instances, dietary treatment with B vitamins resulted in resolution of the nystagmus and improved growth and development of both individuals. Physicians, especially pediatricians and ophthalmologists, should be alert to the possibility of a Wernicke's type nystagmus in such infants, since the diagnosis may be critical to accurate diagnosis and treatment.