Guillain-Barré syndrome in Pakistan: similarity of demyelinating and axonal variants.

Guillain-Barré syndrome (GBS) comprises multiple subtypes whose nosological and pathophysiologic interrelationships are unclear. In an attempt to better understand the relationship between the disease's major subtypes, we reviewed the characteristics of GBS cases consecutively admitted to a tertiary care hospital in Karachi, Pakistan, over a 13-year period. Of 175 cases, 80 (46%) were demyelinating and 55 (31%) axonal, whilst 40 (23%) had ambiguous electrophysiological findings precluding classification. The three groups differed in severity of weakness at presentation (axonal approximately ambiguous > demyelinating; P = 0.002 for arm strength and P = 0.025 for leg strength); mean age (demyelinating > axonal > ambiguous; P = 0.05); and mean cerebrospinal fluid protein concentration (demyelinating > ambiguous > axonal; P = 0.05). However, they were similar in several other respects, including gender ratio, proportion of pediatric cases, history of antecedent infection, length of hospital stay, need and duration of mechanical ventilation, and functional outcome at discharge. Stool culture data was available for 146 (83%) cases in the study; none was positive for Campylobacter jejuni. GBS in Pakistan comprises a high proportion of axonal cases. Similarity of outcomes in axonal and demyelinating variants and lack of C. jejuni stool culture positivity are atypical features.