Relationship between cerebrospinal fluid protein level and electrophysiologic abnormalities in the acute inflammatory demyelinating polyradiculoneuropathy variant of Guillain-Barré syndrome.

Objective: Guillain-Barré syndrome (GBS) is an autoimmune disease characterized by weakness in limbs or cranial nerve innervated muscles. Acute inflammatory demyelinating polyradiculoneuropathy (AIDP) is the most common variant. Electrophysiologic abnormalities and elevated cerebrospinal fluid (CSF) protein are frequently present in AIDP, but the relationship between these two parameters is not well known. We aimed to fill this gap by studying this relationship. Methods: This was a prospective cross-sectional study conducted for two years in the Department of Neurology, Dr. Ruth K. M. Pfau Civil Hospital, Karachi, Pakistan. All 90 adult patients with the AIDP variant of GBS were selected. Nerve conduction studies were performed to determine the degree of demyelination through the four electrophysiologic demyelination criteria. The CSF sample was sent to lab immediately after lumbar puncture. SPSS version 20.0 was used. The CSF protein level was measured with mean ±SD. Demyelination criteria were measured in frequency and percentages. Chi-square test was applied to a number of demyelination criteria and T-test/ANOVA was applied on mean CSF protein level. Results: We found a mean CSF protein of 37.41 mg/dl (±3.69) with one demyelination criterion, 81.87 mg/dl (±17.39) with two demyelination criteria, 119.75 mg/dl (±31.42) with three demyelination criteria, and 134.00 mg/dl (±42.87) with four demyelination criteria (P-value <0.001). Conclusion: This study demonstrates a significant relationship between CSF protein levels and degree of demyelination in the AIDP variant of GBS. This is an under-researched area in GBS and this study adds favorably to limited data in this regard.