Guillain-Barré syndrome (GBS)

• AIDP (acute inflammatory demyelinating polyneuropathy)
• AIP (acute infective polyneuropathy)
• LGBSS ( Landry-Guillain-Barré- strohl syndrome)
• AIP (acute idiopathic polyneuropathy)
• Landry’s ascending paralysis
• French polio
• Landry guillain barre syndrome

Although there is no definite etiology of GBS there are certain factors which have been found to predispose to the occurence of GBS.

• Age: common between 15 to 25 year of age.
• Infection: viral in the form of Epstein Barr virus, bacteria in the form of mycoplasma pneumonia and campylobacter  jejuni( most common)
• Vaccination: Rabies, typhoid tetanus or influenza vaccination may precipitate the attack of GBS.
• Surgery: After 4 to 5 weeks of major surgery patient may show signs of GBS which can be attributed to the following reasons: release of neural antigen that provokes autoimmune response, due to surgical stress, because of blood  transfusion.
• Drugs: Prolonged use of antidepressant drugs like zimelidine or gold therapy which are neurotoxins are found to cause GBS.
• Autoimmune: Due to the presence of antigen CD+ve Tcells
• Idiopathic: without any known causes.

Both antibody and cell-mediated reactions to peripheral nerve myelin are involved. some patient produce antibodies to myelin glycoproteins or gangliosides, other develop a T cell-mediated assault on myelin basic protein.

Segmental demyelination results with secondary axonal damage if the process is severe. perivascular infiltration with lymphocytes occurs within peripheral nerves and nerve roots. lymphocytes and macrophages release cytotoxic substance ( cytokines) which damage schwann cell/myelin.

When axon damage and nerve cell death occur, regeneration cannot take place.

Why nerve conduction blockage?

because we know that in the nerve transmission of impulse by saltatory conduction. this saltatory conduction is maintained by myelin sheath→myelin sheath are destructed →so this saltatory conduction is hampered→so there is nerve conduction is slowed.

a) WEAKNESS

• Onset is gradual and progresses overweeks
• Lower extremities (unable/refusal to walk)→trunks→upper limbs→bulbar muscles→flaccid tetraplegia =LANDRY ASCENDING PARALYSIS
• Proximal and distal muscles are involved relatively symmetrically, but asymmetry is found in 9% of patient.

b) MUSCLE TENDERNESS– At the onset.

c) PARAESTHESIAS – in some cases.

d) AREFLEXIA (83%)

• it is usually due to asynchronization in the  firing by the motor axon.
• synchronization of the discharge along the reflex arc is very essential to elicit a monosynaptic reflex.
• in GBS as there is demyelination it causes lack of synchronization in the firing by the motor axon.

e) BULBAR INVOLVEMENT (50%)

• Dysphagia and facial weakness- signs of impending respiratory failure.
• Interfere with eating. increase risk of aspiration

f) CRANIAL NERVE INVOLVEMENT (50%)

• facial nerve
• oculomotor nerve

g) MYALGIA OR MUSCULAR PAIN

• It occurs because of release of a substance called cytokinin by the macrophages at the inflammatory foci of the nerve terminal.
• this substance causes damage to the muscles thereby irritating the nerve ending in the muscles.

h) SPHINCTER DISTURBANCE

• Retention or overflow incontinence

i) AUTONOMIC DISTURBANCE

• Orthostatic hypotension
• lability of blood pressure
• profound bradycardia

Once thought to be a single disorder, Guillain-Barre syndrome is now known to occur in several forms. The main types are:

• Acute inflammatory demyelinating polyradiculoneuropathy (AIDP), The most common sign of AIDP is muscle weakness that starts in the lower part of your body and spreads upward.
• Miller Fisher syndrome (MFS), in which paralysis starts in the eyes (opthalmoplegia), ataxia, areflexia are also present.
• Acute motor axonal neuropathy (AMAN) and acute motor-sensory axonal neuropathy (AMSAN).

The following tests are used to help confirm a diagnosis:

Spinal tap                                              

A spinal tap involves taking a small amount of fluid from your spine in your lower back. This fluid is called cerebrospinal fluid. Your cerebrospinal fluid is then tested to detect protein levels. People with Guillain-Barré typically have higher-than-normal levels of protein in their cerebrospinal fluid. This test is also referred to as a lumbar puncture.

Electromyography

An electromyography is a nerve function test. It reads electrical activity from the muscles to help your doctor learn if your muscle weakness is caused by nerve damage or muscle damage.

Nerve conduction tests

Nerve conduction studies may be used to test how well your nerves and muscles respond to small electrical pulses.

-Symmetric limb weakness with diminished or absent reflexes.

-Minimal loss of sensation despite paresthesias

-Signs of autonomic dysfunction are present in 50 percent of patients, including-

• cardiac dysrhythmias (asystole, bradycardia, sinus tachycardia, and atrial/ventricular tachyarrhythmias)
• orthostatic hypotension
• transient or persistent hypertension
• paralytic ileus
• bladder dysfuction
• abnormal sweating

SUPPORTIVE CARE: supportive care in HDU/ICU with prevention of respiratory and autonomic complications provides the best chance of a favourable outcome.

• A breathing machine ( ventilator), if patient have difficulty in breathing.
• A feeding tube, if patient have swallowing problems
• painkillers
• Being gently moved around on a regular basis to avoid bed sores and maintain joint mobility
• A thin tube called a catheter in your urethra ( the tube that carries urine out of the body)
• laxatives if patient have constipation
• medication or special leg stocking to prevent blood clots.

IMMUNOTHERAPY: Plasmapheresis and intravenous immunoglobulin(IVIG) are the two main immunotherapy treatment for GBS

Plasmapheresis (plasma exchange)

The immune system produces proteins called antibodies that normally attack harmful foreign substances, such as bacteria and viruses. Guillain-Barré occurs when your immune system mistakenly makes antibodies that attack the healthy nerves of your nervous system.

Plasmapheresis is intended to remove the antibodies attacking the nerves from your blood. During this procedure, blood is removed from your body by a machine. This machine removes the antibodies from your blood and then returns the blood to your body.

Intravenous immunoglobulin

High doses of immunoglobulin can also help to block the antibodies causing Guillain-Barré. Immunoglobulin contains normal, healthy antibodies from donors.

Plasmapheresis and intravenous immunoglobulin are equally effective.

Guillain-Barre syndrome affects your nerves. Because nerves control your movements and body functions, people with Guillain-Barre may experience:

• Breathing difficulties. The weakness or paralysis can spread to the muscles that control your breathing, a potentially fatal complication. Up to 30 percent of people with Guillain-Barre syndrome need temporary help from a machine to breathe when they’re hospitalized for treatment.
• Residual numbness or other sensations. Most people with Guillain-Barre syndrome recover completely or have only minor, residual weakness, numbness or tingling.
• Heart and blood pressure problems. Blood pressure fluctuations and irregular heart rhythms (cardiac arrhythmias) are common side effects of Guillain-Barre syndrome.
• Pain. Up to half of people with Guillain-Barre syndrome experience severe nerve pain, which may be eased with medication.
• Bowel and bladder function problems. Sluggish bowel function and urine retention may result from Guillain-Barre syndrome.
• Blood clots. People who are immobile due to Guillain-Barre syndrome are at risk of developing blood clots. Until you’re able to walk independently, taking blood thinners and wearing support stockings may be recommended.
• Pressure sores. Being immobile also puts you at risk of developing bedsores (pressure sores). Frequent repositioning may help avoid this problem.
• Relapse. Around 3 percent of people with Guillain-Barre syndrome experience a relapse.