Date post: | 14-Jan-2015 |
Category: |
Health & Medicine |
Upload: | saquib-khan |
View: | 2,376 times |
Download: | 11 times |
GUILLAIN BARRE
SYNDROME
MOHD SAQUIB KHAN
M.Sc 3rd SEMESTER
DEPARTMENT OF BIOCHEMISTRY & MOLECULAR BIOLOGY
PONDICHERRY UNIVERSITY
INTRODUCTION
o Popularly known as “French polio” is an acute inflammatory demyelinating polyneuropathy characterized by progressive muscle weakness and areflexia.
o All forms of Guillain–Barré syndrome are autoimmune disease, due to an immune response to foreign antigens.
o It has an annual incidence of 0.6 to 2.4 cases per 100,000
population and occurs at all ages and in both sexes.
o With the marked decline in the incidence of polio, Guillain-
Barré syndrome is now the most common cause of acute
flaccid paralysis in healthy people.
TYPES
o ACUTE INFLAMMATORY DEMYELINATING POLYNEUROPATHY(AIDP)- autoimmune
response directed against Schwann cell membranes.o MILLER FISHER SYNDROME (MFS)- Anti-GQ1b antibodies
are present in 90% of cases.o ACUTE MOTOR AXONAL NEUROPATHY (AMAN) also
known as Chinese paralytic syndrome- Anti-GD3 antibodies are found more frequently in AMAN.
o ACUTE PANAUTONOMIC NEUROPATHY- associated with a high mortality rate, owing to cardiovascular involvement, and associated dysrhythmias.
CAMPYLOBACTER INFECTION
o Campylobacter infection is the most commonly identified precipitant of Guillain-Barré syndrome.
o A case-control study involving 103 patients with the disease found that 26% of affected individuals had evidence of recent C. jejuni infection compared with 2% of household and 1% of age-matched controls.
o Seventy percent of those infected with C. jejuni reported a diarrheal illness within 12 weeks before the onset of the neurologic illness.
o The main lesions are acute inflammatory demyelinating neuropathy and, particularly in patients with Campylobacter-associated disease, acute axonal degeneration.
o These changes may be caused by cross-reacting antibodies to GM1 ganglioside (present in high concentrations in peripheral nerve myelin) formed in response to similar epitopes expressed by the infecting Campylobacter strain.
o However, mechanisms other than molecular mimicry may be associated with the production of antibodies to GM1 ganglioside.
ANTIBODIES AGAINST GANGLIOSIDES
o Anti-GD3-Anti-GD3 antibodies have been found in association with specific forms of Guillain-Barré syndrome.
o In vivo studies of isolated anti-GM1 and GD3 antibodies indicate the antibodies can interfere with motor neuron function.
o Anti-GD1a antibodies were highly associated acute motor axonal neuropathy while high titers of anti-GM1 were more frequent indicating that GD1a possibly targets the axolemma and nodes of ranvier..
o Anti-GM1-Levels of anti-GM1 are elevated in patients with various forms of dementia & correlate with more severe Guillain-Barré syndrome.
o Titers to GM1 in other diseases (rheumatoid arthritis, primary Sjögren's syndrome and systemic lupus erythematosus) was also elevated.
o The autoimmune role of anti-GM1 is still unclear.
o Anti-GQ1-Anti-GQ1b are found in Miller-Fisher syndrome.
o Studies of these antibodies reveal large disruption of the Schwann cells.
o Anti-GQ1b IgG levels were elevated in patients with ophthalmoplegia in Guillain-Barré syndrome.
PATHOGENESIS
o In Guillain-Barré syndrome, the myelin sheath surrounding the axon is lost.
o Demyelination is a common response of neural tissue to many agents and conditions, including physical trauma, hypoxemia, toxic chemicals, vascular insufficiency, and immunological reactions.
o Loss of the myelin sheath in Guillain-Barré syndrome makes nerve impulse transmission is aborted.
CLINICAL MANIFESTATION
o The syndrome may develop rapidly over the course of hours or days, or may take up to 3 to 4 weeks to develop.
o Most patients demonstrate the greatest weakness in the first weeks of the disorder.
o Patients are at their weakest point by the third week of the illness.
o In the beginning, a flaccid, ascending paralysis develops quickly.
o The patient may first notice weakness in the lower extremities that may quickly extend to include weakness and abnormal sensations in the arms.
o Deep tendon reflexes are usually lost, even in the earliest stages.
o The trunk and cranial nerves may become involved.
o Respiratory muscles can become affected, resulting in respiratory compromise.
DIAGNOSIS
o The history of the onset of symptoms can be revealing because symptoms of Guillain-Barré syndrome usually begin with weakness or paresthesias of the lower extremities and ascend in a symmetrical pattern.
o A lumbar puncture may be performed and reveal increased protein.
o Also, nerve conduction studies record impulse transmission along the nerve fiber.
TREATMENT
o The main modalities of therapy for Guillain-Barré
syndrome include
– Plasmapheresis
– Administration of intravenous immune globulino The first therapy proven to benefit patients with
Guillain-Barré syndrome is plasmapheresis.o This procedure mechanically removes humoral
factors.
o Plasma exchange is recommended for patients who – Are unable to walk unaided – Demonstrate worsening vital capacities – Require mechanical ventilation– Have significant bulbar weakness
o Intravenous immunoglobulin (IVIG) is also useful in managing Guillain-Barré syndrome.
REFERENCE
o Davids, H. "Guillain-Barre Syndrome". Medscape Reference. Retrieved 3 Jan 2012.
o Jump up Mori, M; Kuwabara, S; Fukutake, T; Hattori, T (2002). "Plasmapheresis and Miller Fisher syndrome: analysis of 50 consecutive cases". Journal of neurology, neurosurgery, and psychiatry 72 (5).
o Thomas J.Kindt,Barabara A.Osborne,Richard A.Goldsby.Kuby Immunology 6th edition.
American actor Andy Griffith developed Guillain-Barré syndrome in 1983. Griffith is seen here receiving an award at the White House in 2005.