Guillain-Barré syndrome: a common neurological entity with myriad manifestations.

9 G uillain-Barré syndrome (GBS) is a heterogeneous condition with several variant forms. These acute immune-mediated polyneuropathies are classified under as Guillain-Barré syndrome. Typically, GBS presents as an acute monophasic paralyzing illness preceded by an infection. Typical clinical features of Guillain-Barré syndrome (GBS) are progressive, symmetric muscle weakness associated with absent or depressed deep tendon reflexes. Patients usually present within a few days after onset of symptoms which is most commonly the weakness of lower limbs. GBS usually progresses over a period of about two weeks at times upto 4 weeks by which time patients usually reach the maximum neurological deficit. If the disease progresses beyond 8 weeks the diagnosis is chronic inflammatory demyelinating polyradiculoneuropathy (cIDP). The weakness is very variable ranging from mild difficulty in walking to complete paralysis of all four extremities, motor cranial weakness to life-threatening respiratory muscle weakness. The latter develops in 10 to 25% of patients necessitating ventilatory support. 1 Facial weakness can occur in upto 50 percent and of these 50% may develop oropharyngeal weakness. Occulomotor weakness occurs in about 15 percent of patients. Albeit predominantly a motor disease, paresthesias can occur in the hands and feet in upto 80 percent of patients; however, sensory abnormalities on examination are frequently mild. GBS also affects autonomic nervous system and dysautonomia may occur in 70% of patients and may manifest as tachycardia, bradycardia, hypertension alternating with hypotension, orthostatic hypotension, urinary retention, and loss of sweating. Dysautonomia may be poor prognostic indicator as severe autonomic dysfunction may result in sudden death. 2 Severe cardiac arrhythmias, including bradycardia and asystole, occur in about 4 percent of patients with GBS. Other arrhythmias and electrocardiogram (EcG) changes have also been described; these include atrial fibrillation, atrial flutter, paroxysmal tachycardia, ventricular tachycardia, ST-T changes, Q-T interval prolongation, axis deviation, and various conduction blocks. Some of the atypical features of GBS include papilledema, facial myokymia, meningeal signs, vocal cord paralysis, and even mental status changes. The syndrome of inappropriate antidiuretic hormone secretion (SIADh) has also been reported in association with GBS. 3 GBS is a heterogeneous syndrome with several variant forms. Each form of GBS has distinguishing clinical, pathophysiologic, and pathologic features; acute immune-mediated polyneuropathy (AIDP) being the most common form which occurs in almost 85 to 90 percent of cases. The clinical variant miller Fisher syndrome (MFS), characterized by ophthalmoplegia, ataxia, and areflexia, occurs in 5% of cases. Acute motor axonal …