PPhysiopedia Guillain-Barre Syndrome Introduction

Clinical Presentation: The typical patient with GBS presents 2-4 weeks following a relatively benign gastrointestinal or respiratory illness with complaints of finger dysesthesias and proximal muscle weakness of the lower limbs. The weakness may progress over hours to days to involve the arms, trunk, cranial nerves, and muscles of respiration. Variants of GBS may present as pure motor dysfunction or acute dysautonomia. a. “Typical” 'GBS is an acute, predominantly motor neuropathy involving distal limb paresthesias, relatively symmetric leg weakness, and frequent gait ataxia.

•Most cases will have subsequent arm weakness, and possibly the weakness of facial, ocular, and oropharyngeal muscles.

•Weakness is always bilateral, although some asymmetry in onset and severity is common.

•Proximal muscle weakness very frequent, especially initially, with subsequent distal arm and leg weakness.

•GBS with a descending pattern of weakness seen in 14% cases; onset initially with cranial nerve or arm muscle weakness, followed by leg weakness.

•In 1/3 of cases, the degree of weakness in the arms and legs is roughly equal.

•Reduced or absent reflexes characterize GBS.

•Early loss of reflexes may be due to desynchronization of afferent impulses in reflex arc due to non-uniform demyelination.

•About 70% of patients present with loss of reflexes; less than 5% retained all reflexes during the illness

•The presence of intact reflexes should suggest an alternative diagnosis other than GBS.

•Sensory disturbance

•50% will present with symmetric distal limb paresthesias, before clinically evident limb weakness. Early finger paresthesias suggest a patchy process, unlike the pattern seen with distal axonopathies.

•Paresthesias of trunk or face unusual, but sensory loss over the trunk frequent and a psuedolevel may be evident

•Beware if definite sensory level present as this may suggest structural cord disease

•Dysautonomia: Occurs in about 65% of cases

•More frequent in patients with severe paralysis and ventilator difficulties but may develop in mild cases.

•Most common manifestations include cardiac dysfunction such as sinus tachycardia, sinus bradycardia, sinus arrest and other supraventricular arrhythmias, paroxysmal hypertension, and hypotension (especially postural),

•ICU monitoring necessary because of possible cardiac complications.

•Other features: ileus, urinary retention (1/4 cases), inappropriate ADH, altered sweating, mild orthostatic hypotension.

•Cranial nerve involvement is observed in 45-75% of patients with GBS. Cranial nerves III-VII and IX-XII may be affected. Common complaints include:

•Facial Palsy, Diplopia, Dysarthria, Dysphagia, Ophthalmoplegia, Pupillary disturbances

•Facial and oropharyngeal weakness usually appears after the trunk and limbs are affected. The Miller-Fisher variant of GBS is unique in that this subtype begins with cranial nerve deficits[12].