Critical Care Registered Nurse (CCRN) Practice Exam

Which test result is indicative of Guillain-Barré Syndrome?

1. Elevated glucose levels in CSF

2. Increased protein levels in CSF

3. Decreased white blood cells in blood

4. Normal serum electrolytes

The correct answer is: Increased protein levels in CSF

In Guillain-Barré Syndrome (GBS), one of the hallmark features observed in the cerebrospinal fluid (CSF) analysis is an increased protein level, often referred to as albumino-cytological dissociation. This means that while the white blood cell count remains normal or slightly elevated, the protein concentration in the CSF is significantly higher. This finding is critical in diagnosing GBS and helps differentiate it from other neurological disorders. The increase in protein level is thought to occur due to a breakdown of the blood-nerve barrier and inflammatory processes that affect the peripheral nervous system, leading to the characteristic symptoms of muscle weakness and sensory changes. Understanding this pathology highlights why a rise in protein levels is a key indicator of GBS and plays an important role in the diagnostic workup for patients presenting with signs consistent with this syndrome.