A 32-year-old female presents with a seven-month history of recurrent brief episodes of weakness and tingling in the extremities, diplopia, and vertigo. The most likely diagnosis is

• A. Guillain-Barré syndrome
• B. Myasthenia gravis
• C. Multiple sclerosis
• D. Amyotrophic lateral sclerosis

Answer: (C)

The pattern being tested is how multiple sclerosis presents as episodes of neurologic dysfunction that occur in different parts of the CNS over time. In this scenario a young woman has recurring, brief episodes of weakness and sensory tingling, plus diplopia and vertigo. That combination points to demyelinating lesions in various CNS regions (spinal cord, optic pathways, brainstem), with time-separated attacks—classic for multiple sclerosis.

Why this fits best: MS commonly presents in young women with relapsing–remitting episodes that affect different CNS areas, leading to varied symptoms such as sensory changes, visual disturbances from optic nerve involvement, and vertigo from brainstem or cerebellar pathways. The episodic nature and dissemination in time and space are key.

Why the others fit less well: Guillain-Barré syndrome typically causes rapidly progressive, ascending weakness with reduced reflexes and little to no sensory or visual involvement, and it does not usually present with relapsing episodes separated by time. Myasthenia gravis causes fluctuating fatigable weakness, often with ocular symptoms, but sensory disturbances and vertigo are uncommon, and it’s not characterized by multiple CNS lesions over time. Amyotrophic lateral sclerosis presents as progressive motor weakness with both UMN and LMN signs and does not typically involve optic symptoms or recurring acute episodes.