POLYNEUROPATHIES Flashcards
What is triad of polyneuropathies?
Stocking glove distribution, hyporeflexia, distal weakness
Are most poly’s axonal or demyelinating?
Axonal; length dependent/distal to proximal gradient
What type of gradient do demyelinating polys have?
proximal to distal ie GBS, IDP, porphyria and DM polyradiculopathy
What are some signs of demyelinating poly?
Global areflexia/hyporeflexia, hypertrophic nerves and mm weakness w/o atrophy
What reflexes are lost usually with axonal poly?
Normally only the ankle jerk
What are some acquired demyelinating polys?
GBS/AIDP, CIDP, MMN, HIV, Diptheria and toxic
What are NCS findings of acquired demyelinating polys?
Patchy demyelination with conduction block and increased temporal dispersion; occur in noncommon entrapment sites. ie: forearm
What are some inherited demyelinating polys?
HSMN/CMT and HNPP- uniform slowing
What could be causing assymetric findings on NCSs?
mononeuropathy multiplex (vasculitis) or CIDP
Describe GBS/AIDP.
rapid ascending paralysis, distal paraesthesias in fingers and toes same time, hypo/areflexia, bulbar weakness (dysarthria,dysphagia)
What is the best prognostic indicator for GBS/AIDP?
Distal CMAP at 3-4wks; <20% LLN=poor prognosis
Describe CIDP clinical findings.
Acquired, 50-60yo, prox and distal mms, slow progressive wks to months, gait ataxia; +Rhomberg, areflexia/hyporeflexia,
Describe CIDP NCS/EMG findings.
decreased CV with prolonged latencies, assymetric CB/temporal dispersion. EMG- decreased recruitment with large MUAPs, +paraspinals, will improve with plasma xchange or corticosteroids
Describe GBS/AIDP findings.
Delayed F-waves and sural sparing (abnormal median w/normal sural)
Describe multifocal motor neuropathy MMN.
progressive assymetric weakness and atrophy;
What are some medical condition polys?
Diabetic, Uremic(renal), ETOH and malignant
What are some inflammatory or infectious polys?
GBS, leprosy/Hansen’s disease, Diptheric
What are some metabolic polys?
toxic (lead, arsenic and chemo)
What are some inherited polys?
CMT/HSMN and HNPP
HNPP is hereditary but has multifocal multiplex pattern…no uniform slowing in all segments like CMT
What are the demyelinating polys of CMT/HSMN?
CMT I, CMT III/Dejerene Sottas, CMT IV/Refsum’s disease
What is another name for CMT III and who does it affect?
Dejerine Sottas—-infants
What is another name for CMT IV and what does it affect?
Refsum’s disease—ataxic neuro
What are axonal polys of CMT/HSMN?
CMT II and CMT V-Spinocerebellar degeneration
Poly Edx protocol is?
3 or more limbs, 2 motor, 2 sensory, 2 F-waves each limb, EMG all 4 limbs prox and distal
Uniform demyelinating, mixed sensorimotor polys
CMT I, III and IV
Segmental demyelination, motor>sensory polys
GBS/AIDP, CIDP or HNPP
Axon loss, motor>sensory polys
GBS, CMT II and V, lead and vincristine
Axon loss, mixed sensorimotor polys
ETOH, RA, SLE, metals (arsenic, gold, silver), AIDS
Mixed axon loss, demyelinating polys
DM and uremic(renal)
Describe ETOH neuropathy.
insidious onset of slow progressive sensorimotor poly
Describe clinical findings of ETOH neuropathy.
N/T, paraesthesia/burning pain/ reduction to all sensory modalities in stocking glove distribution, worse in LE vs UE, AJ absent
Describe NCSs/EMG findings in ETOH neuropathy.
CMAP tib/peroneal, Sural SNAP- decreased amp and CV EMG- distal lower limb; fibs and decreased recruitment
Describe Polydiabetic neuropathy/Distal symmetric sensory polyneuropathy (DSPN).
Length dependent; sensory loss toes-legs-fingers-proximal, stocking glove/sensory loss to all modalities
Describe NCSs/EMG findings of polydiabetic neuropathy.
Snaps Key! decreased CV, amplitudes, sural/plantar/H-reflex, CMAPs slow EMG- decreased MUAP recruitment
DM amyotrophy=’proximal DM neuropathy’=diabetic polyradiculoneuropathy
Older pnts with type II DM, prox LE assymetric weakness may have had severe wt loss starts unilaterally w/severe pain in back, hip and thigh f/b days-wks atrophy and weakness of proximal and distal mms of affected leg
What are EMG findings of DM amyotrophy/diabetic polyradiculoneuropathy?
SNAPs absent or decreased amplitude, CMAP decreased in affected mms; CV normal or mild slow EMG-fibs in femoral/obturator and paraspinals with decreased recruitment
Describe amyloid neuropathy aka family amyloid polyneuropathy ‘FAP’.
protein ‘amyloid’ deposited in tissues and nerves (this causes nerve to degenerate) affects peripheral sensory, motor and autonomic protein deposits in endoneurium leads to axonal loss and demyelination
What are NCSs/EMG findings of amyloid neuropathy?
SNAPs decreased amps with mild slow CV, CMAP less affected. EMG- fibs in weak distal mms with decreased recruitment
What is the treatment for multifocal motor neuropathy?
IVIG, does not respond to plasma xchange or predisone
Describe HNPP.
Can be assymetric, gene disorder of chromosome 17/PMP 22, which causes decreased myelin formation. These patients are susceptile to pressure palsies.
Have prolonged latencies and decreased CVs across common entrapment sites.
Differeniate between CIDP and MMN.
MMN you have asymetric findings only in motor nerves. Typically in the hand but could involve one foot or one hand.
CB and temporal dispersion across non common entrapment sites.
What does it mean if you find demyelination across a non common entrapment sites?
Red flag make you think that the immune system is attacking the nerve which is causing the demyelination.
Possible its an autoimmune issue, cause normal people don’t get demyelination at non common entrapment sites.
What is this type of distribution and what type of polyneuropathy is it most common to?
Stocking glove distribution and most common in axonal ‘length dependent’ polyneuropathies
What is this type of distribution and what disorders would have this presentation?
Multiplex distribution which is assymetric.
Mononeuropathy Multiplex and Multifocal Motor Neuropathy
