26th August 2024

A 72-year-old woman is being worked up for a subacute onset of muscle weakness and pain

A 72-year-old woman is being worked up for a subacute onset of muscle weakness and pain. She has a past medical history of hypertension, osteoarthritis, glaucoma, and hyperlipidaemia. She takes lisinopril, amlodipine, atorvastatin, paracetamol and methotrexate. She has been recently treated for a lower respiratory tract infection but feels this has recovered reasonably well.

On examination, she has proximal weakness with pain on palpation of proximal muscles. Neurological examination is otherwise normal. What is the most likely cause of her symptoms?

Select the SINGLE most appropriate option from the list below. Select ONE option only.