Solved

A 36-Year-Old Man Has Had Weakness in His Right Arm

question 180

Multiple Choice

A 36-year-old man has had weakness in his right arm and leg as well as difficulty walking over the past 2 weeks. This was preceded for several days by mild headaches and dizziness that have not recurred. He is an ex-smoker with a 10-pack-year history. The patient experimented with cocaine in college although never intravenously, and he has used no illicit drugs in the last 10 years. He has a history of multiple sexual partners and has been treated twice in the past several years for gonococcal urethritis. He also reports an ulcerative lesion on his penis "a while ago," that resolved. The patient has no history of diabetes or hypertension. His family history is negative for stroke or premature coronary artery disease. He is afebrile, his blood pressure is 132/80 mm Hg, and his heart rate is 85/min with a regular rhythm. There is no murmur on cardiac examination. His reflexes are hyperactive on the right side. Electrocardiogram shows normal sinus rhythm. A urine toxicology screen is negative. Brain MRI demonstrates a subacute stroke in the left frontal lobe. HIV test is negative. Cerebrospinal fluid analysis results are as follows: Cerebrospinal fluid Gram stain shows no organisms. Which of the following is most likely to indicate the underlying etiology of this patient's symptoms?

Definitions:

Posterior Portions

The back parts of the body or structures situated nearer to the rear or hind end.

Cerebrospinal Fluid

The clear, colorless body fluid found in the brain and spinal cord, acting as a cushion and providing basic mechanical and immunological protection.

Cranial Cavity

The space within the skull that houses the brain, part of the dorsal body cavity.

Vertebral Canal

The cylindrical space within the vertebral column that houses and protects the spinal cord.