Acute respiratory failure is a frequent complication of Guillain-Barré syndrome, associated with high morbidity and mortality. Adjuvant treatments are needed to improve the outcome of Guillain-Barré syndrome. Since dysglycemia is a risk factor for development of axonal polyneuropathy in critically ill patients and since insulin therapy may be neuroprotective, we sought to explore the association between dysglycemia and neurologic status in Guillain-Barré syndrome patients.