Acute Psychotic Depression as a Sole Manifestation of Vitamin B 12 Deficiency

Abstract

Deficiency of vitamin B12 has a well-established association with a wide variety of neurologic and psychiatric manifestations. The psychiatric presentation of vitamin B12 deficiency may include dementia, delirium, mood disorder (especially depression), personality change, and acute or chronic psychosis. The main neurologic conditions frequently found in chronic B12 deficiency are posterolateral myelopathy, peripheral neuropathy, and optic atrophy. In rare instances, the psychiatric disturbances may occur as the main or sole symptom, in the absence of any neurologic or hematologic abnormalities. We report a case of a 64-year-old non-vegetarian male who presented with severe psychotic depression associated with vitamin B12 deficiency. The patient did not display any of the typical neurologic or hematologic abnormalities of the vitamin deficiency. While the treatment with antipsychotic and antidepressant drugs had little effect, the addition of vitamin B12 facilitated a complete recovery. This case suggests that B12 deficiency can present as an acute psychotic episode.