Background: A 71 year-old man with a history of partial gastrectomy presented to the emergency department with subacute gait instability associated with painful dysesthesias and clumsiness in both hands. 10 years before presentation he had received a diagnosis of megaloblastic anemia, with no neurological involvement, as a result of vitamin B(12) and folate deficiency, for which he was receiving regular supplements.
Investigations: Neurological examination; routine laboratory testing; MRI of the spine and brain; lumbar puncture; electromyography; sensory, motor and visual evoked potentials, optic nerve optical coherence tomography; immunoelectrophoresis; cryoglobulins; immunological and infection tests; screening for onconeural antibodies; measurement of serum metabolic values, including vitamins B(12) and E, folates, homocysteine, copper, zinc and pyruvic acid; transketolase activity; gastrointestinal endoscopies; and the glucose breath test.
Diagnosis: Subacute sensory ataxia with bilateral optic neuropathy related to thiamine deficiency resulting from remote partial gastrectomy.
Management: Parenteral thiamine supplementation followed by chronic oral thiamine and short-term, low-dose multivitamins.