Guillain Barre Syndrome
Guillain-Barre Syndrome (GBS)
Iman binti Jeffrey 0611750
Outline
Definition Epidemiology Etiology Pathogenesis & Pathology Clinical features Investigations Diagnosis Differential diagnosis Treatment Prognosis
Definition
Postinfectious polyneuropathy involving mainly motor but sometimes also sensory and autonomic nerves Affects people of all ages and is not
hereditary
Most patients have a demyelinating neuropathy, but primarily axonal degeneration is documented in some cases. also known as: Acute inflammatory demyelinating polyneuropathy (AIDP)
Epidemiology
usually in children over 4-9 years overall frequency is 1.9 cases per 100,000 population follows infection or immunization by 10 days follows respiratory tract infection or gastrointestinal infection
Etiology
GIT infection Campylobacter jejuni (26-41%) Cytomegalovirus (10-22%) Respiratory tract infection Mycoplasma pneumoniae Ebstein-Barr virus (10%) Vaccines
Rabies Avian-flu influenza
Pathogenesis
Molecular mimicry
Cross-reactive immune attack by host Ab & T cell with are directed against the pathogen & nerve components.
Eg: Campylobacter jejuni
Immune response directed against capsular LPS producing Ab cross-reacting with myelin to cause demyelination (mimics the gangliosides)
Pathogenesis
Presentation of Ag to naïve T cell → activation ↓ Activated T cells attach to venular endothelium of peripheral nerves ↓ Migrate through endothelial lining to perivascular location ↓ Sensitized → contact myelin → segmental demyelination
Pathology
Inflammatory lesions scattered throughout the peripheral nervous system Circumscribed areas of myelin loss associated with presence of lymphocytes and macrophages Initial lesion: nodes of Ranvier Myelin damage: penetration of macrophages into basement membrane around nerve fibers & strip myelin away Severe cases: interruption of axon & wallerian degeneration
Clinical Features
Weakness
o
Iman binti Jeffrey 0611750
Outline
Definition Epidemiology Etiology Pathogenesis & Pathology Clinical features Investigations Diagnosis Differential diagnosis Treatment Prognosis
Definition
Postinfectious polyneuropathy involving mainly motor but sometimes also sensory and autonomic nerves Affects people of all ages and is not
hereditary
Most patients have a demyelinating neuropathy, but primarily axonal degeneration is documented in some cases. also known as: Acute inflammatory demyelinating polyneuropathy (AIDP)
Epidemiology
usually in children over 4-9 years overall frequency is 1.9 cases per 100,000 population follows infection or immunization by 10 days follows respiratory tract infection or gastrointestinal infection
Etiology
GIT infection Campylobacter jejuni (26-41%) Cytomegalovirus (10-22%) Respiratory tract infection Mycoplasma pneumoniae Ebstein-Barr virus (10%) Vaccines
Rabies Avian-flu influenza
Pathogenesis
Molecular mimicry
Cross-reactive immune attack by host Ab & T cell with are directed against the pathogen & nerve components.
Eg: Campylobacter jejuni
Immune response directed against capsular LPS producing Ab cross-reacting with myelin to cause demyelination (mimics the gangliosides)
Pathogenesis
Presentation of Ag to naïve T cell → activation ↓ Activated T cells attach to venular endothelium of peripheral nerves ↓ Migrate through endothelial lining to perivascular location ↓ Sensitized → contact myelin → segmental demyelination
Pathology
Inflammatory lesions scattered throughout the peripheral nervous system Circumscribed areas of myelin loss associated with presence of lymphocytes and macrophages Initial lesion: nodes of Ranvier Myelin damage: penetration of macrophages into basement membrane around nerve fibers & strip myelin away Severe cases: interruption of axon & wallerian degeneration
Clinical Features
Weakness
o
References: Menkes & Sarnat: Child Neurology, 6th ed. USA, Lippincott Williams & Wilkins, 2000 Aicardi, Jean: Clinics in Developmental Medicine: Diseases of The Nervous System in Childhood, 2nd ed. London, Mac Keith Press, 1998 Behrman, Kliegman, Jenson: Nelson Textbook of Pediatrics, 17th ed. China, Elsevier Saunders, 2004