PNS Demyelinating Disorders Flashcards
GB - Definition
Demyelinating disease of the PNS - a number of variants exist
Classic form is Acute Inflammatory Demyelinating Polyneuropathy (AIDP)
GB - other names you may hear
Postinfectious polyneuritis
Acute infectious polyneuritis
Landry-GB
GB - Chronic Inflammatory Demyelinating Polyradiculoneuropathy (CIDP)
Chronically progressive or relapsing motor and sensory dysfunction
Symmetrical
GB - CIDP - associated with
Lymphocyte and macrophage infiltrations of perivascular region of a nerve
GB - Acute inflammatory demyelinating polyneuropathy (AIDP) - epidemiology
1-3/100,000
Can occur at any age but usually 15-30, 50-75
M more than F
Physiologic stress may play role in onset
GB - Acute inflammatory demyelinating polyneuropathy (AIDP) - Etiology
Unknown Immune system disorder Misdirected allergic response Environmental causes Infection - usually respiratory or GI
GB - Acute inflammatory demyelinating polyneuropathy (AIDP) - some known antecedent events
Viral infections Spirochetal infection Bacterial infections Vaccination Surgery Pregnancy
GB - Acute inflammatory demyelinating polyneuropathy (AIDP) - Known antecedent events - stronger associations with GB development
Viral - Cytomegalovirus, Epstein Barr, Zika
Bacterial - Camplyobacter jejuni, mycoplasma pneumoniae
GB - Acute inflammatory demyelinating polyneuropathy (AIDP) - Pathology
Multifocal neuropathy - ventral (anterior) root ganglia - motor
Inflammatory response with demyelination of axon of PNs
GB - Acute inflammatory demyelinating polyneuropathy (AIDP) - Demyelination occurs from
Distal to proximal
GB - Acute inflammatory demyelinating polyneuropathy (AIDP) - 2 main pathologic processes
Primary demyelination Axonal degeneration (this one will lead to more damage in the end)
GB - Acute inflammatory demyelinating polyneuropathy (AIDP) - Diagnosis
CSF
Electrodiagnostics
Clinical findings
GB - Acute inflammatory demyelinating polyneuropathy (AIDP) - Diagnosis - CSF
Increased proteins
Normal cell counts
GB - Acute inflammatory demyelinating polyneuropathy (AIDP) - Diagnosis - Elecrodiagnosis
Not as useful in early stages
EMG, conduction blocks and demyelination effects
80% have dec nerve conduction velocity
GB - Acute inflammatory demyelinating polyneuropathy (AIDP) - Diagnosis - 3 out of 4
1 Reduced nerve conduction velocity
2 Conduction block or abnormal dispersion
3 Prolonged distal latencies
4 Prolonged F waves