Peripheral Neuropathies Flashcards
Polyneuropathy
Symmetrical distal sensory loss with burning or weakness.
Med rxn or systemic dz
Can be axonal or demyelinating
Guillain-Barre Syndrome (GBS)
Acute immune-mediated group of polyneuropathies, usually provoked by preceding infection.
GBS Patho
Acute inflammatory demyelinating polyneuropathy (AIDP)
Can be caused by preceding infxn, immunizations, surgery
Generation of antibodies against galgliosides that cause an immune response against axons
Which bug usually causes GBS?
Campylobacter Jejuni
also CMV, EBV
GBS clinical features
Symmetrical muscle weakness Decreased DTR's Respiratory involvement Parasthesias in hands and feet Severe back pain
Where does weakness usually start in GBS?
Proximal legs, arm and facial muscles
Dysautonia
Common in GBS
Tachycardia, urinary retention, HTN altering with Hypotension, bradycardia, ileus, loss of sweating.
Therapy for GBS?
Plasmapheresis or IVIG
GBS DIagnosis
LP: Elevated protein
Neurophysiology studies
Bell’s Palsy
Acute peripheral facial palsy of unknown origin
Involves the facial nerve (CN VII)
What does the facial nerve innervate?
Facial motor output
Parasympathetics to salivary glands (including lacrimal)
Taste for anterior 2/3 of tongue
Somatics for EAC and pinna.
Bells palsy Epidemiology
Risk 3x greater in pregnancy
DM is risk factor
Recurrence is common
Bells palsy patho
Herpes virus most likely cause
Can also be other viruses
Ischemia may play a role
Bells palsy clinical presentation
Sudden onset over hours**
Eyebrow sagging, cant close eye
Mouth drawn to non-affected side
Decreased tearing**
Bells palsy course
Onset over hours to 1-2 days
Maximal paralysis within 3 wks of onset
Some degree of recovery by 6 months
Usually recover fully
Bells Palsy Mgmt
Eye care (drops)
Glucocorticoid therapy within 3 days of onset
For severe, valcyclovoir
Myasthenia Gravis (MG)
Autoimmune disorder characterized by weakness and fatiguability of skeletal muscle.
Decrease in number of acth receptors
What are the antibodies against in MG?
Acetylcholine receptors (AchR-Ab)