Professional and Linguistic Assessments Board (PLAB) Practice Exam

In Lambert-Eaton syndrome, which of the following characteristics is commonly observed?

1. Arms weaker than legs

2. Legs weaker than arms

3. Symptoms persist after exertion

4. Loss of reflexes in the upper limbs

The correct answer is: Legs weaker than arms

In Lambert-Eaton Syndrome, the common characteristic observed is that the legs are generally weaker than the arms. This neuromuscular disorder is associated with a disruption in the release of acetylcholine at the neuromuscular junction, primarily affecting the proximal muscles of the limbs. Due to this condition, patients often display a proximal muscle weakness that tends to be more pronounced in the lower extremities compared to the upper extremities. One significant aspect of Lambert-Eaton Syndrome is that the weakness can improve with repeated use of the affected muscles. This contrasts with conditions like myasthenia gravis, where weakness typically worsens with exertion. Therefore, the typical presentation where the legs are weaker than the arms aligns with the underlying pathophysiology of the disease. While other options may present symptoms related to muscle weakness or reflexes, they do not accurately represent the most characteristic feature of Lambert-Eaton Syndrome.