Objective: To describe a case of vitamin B(12) deficiency with classic and rare clinical features and novel radiographic features.
Design: Case report.
Setting: Johns Hopkins Hospital neurology service.
Patient: Middle-aged man with neuropathy, myelopathy,impaired cognition, and extrapyramidal signs.
Results: The patient had neurologic and hematologic signs of vitamin B(12) deficiency, with elevated methylmalonic acid and homocysteine levels. Brain magnetic resonance imaging showed signal abnormality in the globi pallidi, as can be seen in inherited methylmalonic acidemia.The clinical and radiographic findings reversed with vitamin B(12) administration.
Conclusion: Vitamin B(12) deficiency can present with extrapyramidal symptoms and reversible bilateral globus pallidus abnormalities.