Vitamin B₁₂ deficiency: an unusual cause of vocal fold palsy

We report an extremely rare case of vocal fold palsy secondary to vitamin B12 deficiency.

Case report and English-Language review of the world literature concerning vitamin B12 deficiency and its neurological manifestations. We discuss the physiological role of vitamin B and its specific relationship to the presented patient's symptoms.

We describe a rare instance of a patient presenting with bilateral lower limb weakness and unilateral vocal fold palsy, as a manifestation of vitamin B12 deficiency. Quick recognition and treatment resulted in a full recovery.

To our knowledge, this is the first reported case of unilateral vocal fold palsy secondary to vitamin B12 deficiency. Central and peripheral neuropathies have been described; however, other than the optic nerve, the cranial nerves are very rarely affected. It is important to consider vitamin B12 deficiency as a cause, as speedy identification and treatment can help prevent permanent neurological damage.