27th June 2023

A 55-year-old man presents with gradual difficulty in walking up stairs. He tends to feel stronger at the end of the day

A 55-year-old man presents with gradual difficulty in walking up stairs. He tends to feel stronger at the end of the day. He has lightheadedness on standing, dry mouth, mild ptosis, and weakness in the proximal muscles of his lower limbs with hyporeflexia. He is a smoker and reports some weight loss over the past 6 months.

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