ABIM Neurology

Question 1

For an eligible patient with acute ischemic stroke, what is the standard time window from last known well for IV thrombolysis (alteplase or tenecteplase)?

Accepted Answer

4.5 hours

Answer

IV thrombolysis is indicated within 4.5 hours of last known well in eligible patients. Mechanical thrombectomy for large-vessel occlusion can extend to 24 hours in selected patients.

Question 2

A patient has acute right facial weakness that includes the forehead, with no other deficits, and presents within 48 hours. What is the most appropriate treatment?

Accepted Answer

Oral prednisone

Answer

Weakness that involves the forehead indicates a peripheral (lower motor neuron) lesion consistent with Bell palsy. Corticosteroids started within 72 hours improve recovery. Antivirals alone are not effective, and a central lesion such as stroke typically spares the forehead.

Question 3

A 35-year-old woman has ptosis and diplopia that worsen through the day, along with fatigable proximal weakness. Which test is most specific for the likely diagnosis?

Accepted Answer

Acetylcholine receptor antibodies

Answer

Fatigable ocular and limb weakness suggests myasthenia gravis. Acetylcholine receptor antibodies are positive in about 85% of generalized cases and are highly specific.

Question 4

A patient has ascending symmetric leg weakness and absent reflexes 2 weeks after a diarrheal illness. Which CSF finding supports the diagnosis?

Accepted Answer

Elevated protein with a normal cell count

Answer

Guillain-Barré syndrome classically shows albuminocytologic dissociation: high CSF protein with a normal white cell count. Serial vital capacity (FVC) monitoring is essential because of the risk of respiratory failure.

Question 5

A patient has a generalized convulsive seizure lasting 7 minutes and has IV access. What is the first-line treatment?

Accepted Answer

IV lorazepam

Answer

A benzodiazepine is first-line for status epilepticus, with IV lorazepam preferred when IV access exists. Levetiracetam, fosphenytoin, or valproate are second-line if seizures continue. Anesthetic infusions are for refractory status.

ABIM - American Board of Internal Medicine Practice Test

ABIM - American Board of Internal Medicine Practice Test

ABIM Neurology