How do electrodiagnostic studies contribute to the diagnosis of Guillain-Barré Syndrome?

Electrodiagnostic studies, such as nerve conduction studies, are essential in the diagnosis of Guillain-Barré Syndrome (GBS) as they reveal specific abnormalities in nerve function. In GBS, one of the hallmark findings is decreased conduction velocities and evidence of demyelination. This is because the syndrome typically involves an autoimmune response that damages the myelin sheath surrounding peripheral nerves. When conducting these studies, clinicians observe that the affected nerves demonstrate slower conduction speeds due to this demyelination.

In addition to revealing decreased conduction velocities, electrodiagnostic studies may show signs of axonal degeneration if the condition progresses. These findings are crucial for distinguishing GBS from other neurological disorders that may present with similar symptoms but have different underlying pathophysiological mechanisms. Thus, the demonstration of decreased conduction velocities and possible demyelination provides significant diagnostic information leading to a conclusive diagnosis of GBS.