Question of the Week
For October 21, 2014
A 65-year-old woman with hypertension, insulin-requiring diabetes mellitus, end-stage kidney disease, and a distant history of cigarette smoking presents with new-onset pain in her right shoulder and weakness in her right hand that have progressed during the past 6 weeks. In addition, she has lost 15 pounds during the past 4 months.
Physical examination reveals a unilateral, right-sided ptosis with a pinpoint pupil of the right eye, as well as muscle atrophy, hand weakness, and numbness in the fourth and fifth fingers of the right hand. No facial plethora is noted. The patient has no pain on percussion of her neck or back.
Which one of the following conditions is the most likely cause of this patient’s symptoms?