Guillain-Barré syndrome (GBS) affects around 1-2 people per 100,000 each year and is a polyneuropathy that often also involves the autonomic system. Peripheral weakness is the most common initial presentation, starting in the hands or the feet. There may be associated pain and parasthesia as the paralysis ascends. Miller Fisher syndrome is a variant of GBS and is the triad of ataxia, areflexia and ophthalmoplegia.

Patients are nearly always hospitalised as there may be serious consequences of autonomic involvement, such as fluctuations in blood pressure and cardiac arrhythmias. Patients may also need ventilation and nasogastric feeding as the diaphragm becomes paralysed, and they can become unable to swallow.

GBS is an autoimmune disease that usually starts within three weeks of an infection. The most common cause is Campylobacter jejuni, followed by Epstein-Barr virus, cytomegalovirus and Mycoplasma pneumoniae. The patient’s response to the foreign antigen, whilst being effective to the initial infection, also targets the host tissue.

Diagnosis is made through clinical examination confirming areflexia and progressive weakness in the legs and often arms. Nerve conduction studies can be used, and a lumbar puncture can be performed that typically shows high protein with few white blood cells.

Treatment is supportive, and immunoglobulins are often utilised to shorten the duration of the illness. Plasma exchange may also be used; however, this has been used less since the advent of immunoglobulin therapy.

Around 80% of patients make a full recovery, but it often involves a hospital stay of many months. The mortality rate is approximately 5%, depending on the facilities available, such as ventilatory support in the acute phase. Around 15% will have some permanent disability such as weakness or pain.