If a patient presents with unilateral weakness and sensory loss, which condition should be quickly evaluated?

When a patient presents with unilateral weakness and sensory loss, the condition that should be quickly evaluated is a hemispheric stroke. This is because strokes, particularly ischemic strokes that occur due to a blockage of blood flow to a part of the brain, can manifest as sudden onset of unilateral symptoms depending on the side of the brain affected. Immediate medical intervention is crucial in these cases, as rapid assessment and treatment can significantly improve outcomes and reduce the risk of permanent disability.

In contrast, while multiple sclerosis can lead to various neurological symptoms, including weakness and sensory loss, it typically presents with a more gradual onset and is often accompanied by other signs like visual disturbances or fatigue that develop over time. Myasthenia gravis may cause muscle weakness, but it usually does not present acutely and is instead characterized by fluctuating muscle strength. An epileptic seizure can lead to temporary weakness postictally, but it would not typically cause persistent unilateral weakness and sensory loss. Thus, in the context of sudden unilateral symptoms, a hemispheric stroke requires the most immediate evaluation and intervention.