A woman with macrocytic anaemia and confusion

Abstract

An 82 year old woman with a history of type 2 diabetes presented with unsteady gait and confusion of two months' duration. Her diabetes was controlled by metformin (500 mg, three times a day) and she had no other comorbidities. She was a non-smoker and did not drink alcohol. Dietary history showed an adequate intake of meat, vegetables, and calories.On examination, her vital signs were stable. She was disorientated in time but not in person or place. Cranial nerve examination was normal but examination of the peripheral nervous system showed ataxia and impaired proprioception of the lower limbs bilaterally. The rest of her examination was normal. Her score on the mini-mental state examination at presentation was 18 out of 30.Correspondence to: A Sugrue