Confusion and Personality Change

🗒️ Question

A 78 year old woman is brought to her GP by her daughter who is concerned about her mother’s recent memory loss and confusion. Over the past six months, the patient has had increasing difficulty remembering recent events, frequently misplaces items and occasionally fails to recognise familiar people. She has also become withdrawn, occasionally displaying mood changes and irritability. Her past medical history includes hypertension for which she is on amlodipine and type 2 diabetes managed with metformin.

On examination, her blood pressure is 135/80 mmHg, heart rate is 72 bpm and she is alert although disoriented to time and place. There are no motor deficits and her speech is fluent.

Investigations

• Haemoglobin: 12.0 g/dL (115–150)

• Serum vitamin B12: 220 pmol/L (140–600)

• Serum TSH: 2.5 mIU/L (0.4–4.0)

• MRI brain: Mild global cortical atrophy

What is the most likely diagnosis?

(A) Alzheimer’s disease

(B) Delirium

(C) Lewy body dementia

(D) Vascular dementia

(E) Vitamin B12 deficiency