question: Which vitamin deficiencies may present with neurologic signs or symptoms?
answer: Many vitamin deficiencies have been described as a cause of neurologic signs and symptoms. For instance, vitamin B12 deficiency can cause several types of neurological manifestations, such as subacute combined degeneration of the spinal cord, ataxia, peripheral polyneuropathy, optic nerve neuropathy, and cognitive disorders. In addition, vitamin B1 (Thiamine) and B6 (Pyridoxine) deficiency can both cause peripheral neuropathy. Specifically, vitamin B1 deficiency can also cause confusion, ophthalmoplegia, nystagmus, and ataxia in the context of beriberi and Wernicke's encephalopathy. Finally, vitamin A deficiency has been described to cause retinal change-related visual defects and subsequent vision loss.