Guide for GP's

By James G McLeod AO, FRCP (Lond), FRACP
Reprinted from Modern Medicine of Australia October 1995

Definition

Guillain-Barré Syndrome is the name given to acute idiopathic polyneuritis in honour of the French neurologists who described the condition in two soldiers in 1916. Undoubtedly there had been earlier descriptions. In brief, it is a clinical syndrome of progressive muscle weakness and respiratory paralysis associated with absent reflexes, which develops over a period of three to four weeks, usually following a viral or other infection.

The annual incidence is about two per 100,000 so that, for example, about 50 to 60 cases would be seen in Sydney each year. Early diagnosis is important since death from rapidly developing respiratory paralysis can occur if the illness is not recognised, and because there are now specific forms of treatment such as plasmapheresis and intravenous immunoglobulin that can help speed up recovery, reduce disability and prevent complications.

Aetiological Factors

Guillain-Barré Syndrome can affect people of any age, but the incidence increases with age and is at its highest in the age group 50 to 74 years. Men are affected more commonly than women. In about 50 to 60% of cases there is a history of a recent viral or other infection. Organisms that have been specifically implicated are Campylobacter jejuni, which causes diarrhoea, and Epstein-Barr virus, which causes glandular fever. Vaccinations may also precipitate its onset. HIV infections may cause a syndrome like Guillain-Barré Syndrome.

Pathogenesis

Guillain-Barré Syndrome is an autoimmune disease, in which there is an attack by macrophages and T-cells on healthy myelin in peripheral and cranial nerves, resulting in a block in conduction of nerve impulses. The central nervous system is unaffected.

Clinical Features

The common initial symptoms are numbness and tingling in the lower limbs (see Table 1). Back pain is a major symptom in about one third of patients. The sensory symptoms are soon followed by weakness in the legs and arms and may be more pronounced in the proximal muscles. Cranial nerves are affected in over 50% of cases; the facial nerves being most commonly involved. The acute onset of bilateral facial palsy (in contrast to unilateral Bell's palsy) should immediately raise the suspicion of Guillain-Barré Syndrome. Paralysis of extraocular muscles, causing ptosis and double vision, occurs in about 10% of cases. Weakness in the limbs may be in a proximal as well as a distal distribution. Tendon reflexes are usually absent or greatly reduced, and although sensory loss is usually not profound there may be impairment of sensation in a glove and stocking distribution. Sphincter disturbances are present in only a small proportion of cases and should alert the clinician to the possibility of another diagnosis, such as spinal cord compression. Progression of disability may continue for a period of up to four weeks.