Acquired neuropathies chap:23

1
Acquired neuropathies
chap23
Alireza Ashraf, M.D.Professor of Physical
Medicine Rehabilitation
Shiraz Medical school
2
GBS

• In one report earliest feature
• proximal nerve edema degeneration
• myelin sheath within first week of illness
• In other study prominent perivascular
• inflammation in spinal root ,ganglia ,cranial
• nerve and randomly along peripheral
• nerve

3
Acute inflammatory demyelinating
polyradiculoneuropathy (AIDP)

• Most common cause of acute generalized weakness
• Annual incidence1-4/100000 general population
• Slight male predominance
• Peak age of onset in the 3-4 decade of life
• 60-70 of patient note some form of Acute
  illness 1-3 wk before onset of neurologic
  symptom (C.j 32-CMV 13-EBV 10- M.pnumonia 5)

4

• most patient initially note Tingling and numbness
  in
• distal of lower limb and shortly thereafter in
  the distal
• upper limb
• Large fiber modality (vibration ,touch ,
  position)
• more severly affected than small fiber modality
  (pain
• , temperature)
• A few patient present only with sensory symptom
• but EDX sign of motor involvement are typical
• Major complaint of most patient progressive
• weakness

5

• Mild facial weakness in 50of patient during
• course of illness.
• Occasionally a descending presentation with
• onset in the cranial nerve and progress to the
• arm and leg
• External urethral and anal sphincter usually
• spared .although may be involved in severe
• disease.

6

• Autonomic instability is common in AIDP
• Neonatal GBS in infant of a mother with GBS
  due to Ab
• crossing the placenta.
• The disease usually progresses over the course of
  2-4 wk.
• Progression of symptom and sign for over 8 wk
  excludes
• GBS and suggest the diagnosis of CIDP.
• Respiratory failure in 30
• Neck flexion ,extension and shoulder abduction
  correlate well
• with diaphragmatic strenght and thus important to
  follow closely.

7

• Most patients gradually recover satisfactory
• function over several months
• The mortality rate about 5
• Patient die result of RDS ,aspiration
• Pneumonia ,pulmonary embolism ,arrhythmia and
  sepsis

8

• Risk factor for poor prognosis (slower and
  incomplete recovery)
• age greater than 50-60years,
• abrupt onset of profound weakness,
• need for mechanical ventilation,
• distal CMAP Ampl less than 10-20 of normal.

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Lab feature

• Elevated CSF protein accompanied by no or only a
  few
• mononuclear cell is the characteristic
  laboratory findings and
• evident in over 80 of patient after 2 wk.
• In patient with CSF pleocytosis of more than 10
• Lymphocytes (cell count gt50), AIDP like
  neuropathies related
• to lyme disease, recent HIV infection,
  sarcoidosis need to be
• considered.
• Elevated liver function test evident in many
  patient. In such
• cases important to evaluate for viral hepatitis
  (A,B,C),EBV,
• CMV
• Antiganglioside Ab particularly anti GM1
  correlates well
• with c.j infection.

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histopathology

• The entire peripheral motor and sensory
• nervous system including cranial nerve can be
• involved from the most proximal aspect of the
• ventral and dorsal root to the terminal region
  of
• the intramuscular and sensory nerve fibers.
• An initial preference for the nerve root
• region ,areas where peripheral nerve commonly
• entrapped and the motor nerve terminals.

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Motor NCS

• Electrophysiologic hallmark of demyelination
• prolonged distal latency
• Slow NCV
• Temporal dispersion
• Conduction block
• Prolonged F-wave latency

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• A hallmark is the asymmetric and multifocal
• character of the EDX abnormality
• Always perform F-wave study in both upper
• and lower limb in patients suspected of having
• AIDP because of early predilection for the
• proximal nerve segments and spinal roots.

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• In patient with rapid recovery ,particularly
  after PE or IVIG the improved clinical status
  probably result from coduction block resolution
  rather than remyelination or regeneration of the
  axons.
• Two important caveats about conduction block
• First, 5-7day after acute axonal loss, it is
  impossible to distinguish between axonal loss and
  conduction block
• Second,in acute disease small reduction in CMAP
• Ampl may be result from conduction block however
  ,in
• more chronic disease or later in acute disease
  alteration
• in conduction velocity may result in
  pseudocoduction
• block.

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• Examination of the pherenic and facial nerve
• may be interest in AIDP.
• Facial and supraorbital nerve evaluated with
• direct facial nerve stimulation and blink reflex.
• Maximum degree of motor conduction
• abnormality occure within 3-8 wk.

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• Early abnormalities of distal CMAP Ampl and
  latency and F-wave reflect the early predilection
  for involvement of the proximal spinal roots and
  distal motor nerve terminals in AIDP.

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• There does not appear to be a correlation
• between the nerve conduction velocity or
• distal motor latency and clinical severity of
• the neuropathy ,although distal CMAP
• Ampl less than 10-20 normal are
• associated with a poorer prognosis.

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S-NCS

• Upper limb SNAP particularly median nerve
• affected more severly and earlier than sural
• SNAPs.
• Unlike most axonopathies , in which the
• earliest and most severe abnormalities
• involve the distal lower limb nerve (sural
• SNAP), demyelinating disease are just as
• likely to affect the median and ulnar SNAPs.

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• It can take 4-6wk for SNAP abnormalities to peak.
• The parameter most adversely affected is
• SNAP Ampl.
• Reduced SNAP Ampl can result from
• secondary axonal degeneration ,conduction
• block or phase cancelation.
• With a pure sensory presentation , other
• Disorders (acute sensory neuronopathy or
• ganglionopathy) must be ruled out.

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Needle EMG

• EMG in patients with AIDP is primarily
• adjunctive to explore the possibility of other
• disease entities.
• Earliest finding a reduced number of normal-
• appearing MUAP firing at rapid rate.
• Fib and psw may first be seen between wk 2-
• 4,peaking at about 6-15wkmaximize earlier in
• proximal muscle than in distal muscle.
• Myokymia can be detected especially in facial
• muscles.

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Autonomic testing

• Autonomic instability can be assessed by
  measuring the EKG R-R interval variation.
• A alternative method is SSR.

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Plasma Exchange

• reduced the time necessary to improve one
• clinical grade, time to walk unaided, time on a
• ventilator and percentage of patient improving
• after 1-6 month.
• Total amount of exchanged is 200-250ml/kg
• over 10-14 day.
• The removed plasma is replaced with
• albumin.

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IVIG

• Replaced PE in many centers as the
• treatment choice for AIDP because it is more
• widely available and easer to use than PE.
• Dose of IVIG is 2 gr/kg infused over 2-5 days.
• Treatment should begin preferably within first
  7-10
• day of symptoms.
• Improvement often not immediate .mean time to
• improvement ranged from 6-27 day.
• Unlike CIDP, corticosteroid do not appear
• beneficial in the treatment of AIDP in fact
  ,some
• patient have done worse.

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AIDP in children

• The clinical , lab and EDX findings similar to
  adult
• 75 have an antecedent infection
• Major presenting complaint is pain
• Most children with AIDP have a satisfactory
  recovery , even those with significant reduction
  in CMAP Ampl.

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Acute motor-sensory axonal neuropathy (AMSAN)

• Clinically and at least by initial EDX
• ,patient with AMSAN are indistinguishable
• from AIDP.
• Patient with AMSAN develop rapidly
• progressive and severe generalized
• weakness over only a few day as opposed
• to a couple of wk in most patient with
• AIDP.

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• Ophtalmoplegia and difficulty in swallowing may
  be
• noted.
• Muscle of facial expression are profoundly weak.
• Most patient require ventilator support.
• Sensation to all modality is reduced.
• Complete areflexia is usually evident.
• Prognosis of AMSAN much poorer than AIDP most
  patient have a slow or incomplete recovery.
• Some authorities suggest that C.j infection and
• GM1 Ab are more commonly associated with axonal
• form of GBS.

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• Histologic evaluation performed early in the
• course of disorder is the only way to
  differentiate
• axonal GBS from psudoaxonal GBS.
• Markedly diminish Ampl or absent CMAP within 7-
• 10 day of onset.
• SNAP Ampl are profoundly reduced or absent.
• Markedly abnormal reduction in recruitment .
• Abundant fib and psw detected in most muscle
• especially distal limb.

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Acute motor axonal neuropathy (AMAN)(chinese
paralytic syndrome)

• In northern china, AMAN is the most common
• variant of GBS.
• Serologic evidence of recent C.j infection
• detected in 67- 92 of patient.
• As in AMSAN , there is an abrupt onset of
• generalized weakness.the distal muscle often are
• affected more severly than proximal limb muscle.
• Sensory sign and symptom are absent.
• DTR may be normal or absent.
• Patient generally make a good recovery within one
  years,
• but residual distal limb weakness is common.
• Mortality rate is less than 5

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• The absence of prominent CSF pleocytosis
• help distinguish AMAN from poliomyelitis,
• which it can mimic.
• The fact that many patient with AMAN
• recover quickly suggests that low Ampl or
• unobtainable distal CMAP are due not
• necessarily to axonal degeneration but to
• distal conduction block .

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• Characteristic NCS feature in AMAN is low Ampl or
  unobtainable CMAP with normal SNAP.
• When CMAP are obtained, DML and NCVare normal.
• F-wave usually unobtainable but,when present,
  show normal latency.

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Other variant of GBS

1. Miller fisher syndrome
2. Idiopathic cranial polyneuropathy
3. Pharyngeal-cervical-bracial weakness
4. Para paretic weakness

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Miller fisher syndrome

• M/F2/1 , mean age of onset in the early 40s.
• An antecedent infection in 2/3 of cases.
• Diplopia is the most common initial complaint.
• Whether the ataxia is secondary to sensory
• dysfunction or a cerebellar lesion is
  controversial. In
• our experience , most patient have sensory
  ataxia.
• Ptosis usually accompanies the ophtalmoparesis
• ,but pupillary involvement is uncommon.

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• Nearly 50 of patient describe paresthesia in
  face
• and distal limbs.
• Areflexia is evident in over 82
• anti GQ1b demonstrate in most patient.
• Most prominent EDX abnormality in MFS is
• reduced SNAP Ampl.
• CMAP in the arm and legs are usually normal but,
• mild to moderate reduction in facial CMAP
• demonstrate in over 50 of patient.
• Blink reflex may be abnormal.
• There is generally no abnormal spontaneous
• activity in limb or paraspinal muscles but , fib
  may be
• detected in facial muscle.

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Chronic inflammatory demyelinating
polyneuropathy(CIDP)

• An immune-mediated neuropathy
• characterized by a relapsing or progressive
• course.
• Relapsing formrecurrent polyneuritis
• Progressive formprogressive hypertrophic
• neuritis or chronic GBS
• Sign and symptom of neuropathy must be
• progressive for at least 2 month, which
• distinguishes CIDP from GBS or AIDP.

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• Four typical clinical course of progression
• Chronic monophasic(15)
• Chronic relapsing(fluctuation of weakness or
  improvement over week or months)34
• Stepwise progression 34
• Steady progression15
• Pattern of disease progression in CIDP analogous
  to MS.
• CIDP most commonly present in adult with a peak
  incidence at about 40-60 years slightly
  increased prevalence in men.
• Relapsing form has an earlier age of onset
  ,usually in twenties
• Relapses have associated with pregnancy

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• Most patient present with relapsing or
• progressive symmetric proximal and distal
• weakness of the arms and legs.
• Early in the course of illness ,only distal
• weakness may be observed. however . If
• weakness remain distal , other diagnoses
• need to considered hereditary demyelinating
• neuropathy ,Para protein related neuropathy,
• distal acquired demyelinating neuropathy.

40

• Although most patient (80)have both
• motor and sensory involvement , a few patient
• may have pure motor (10) or pure
• sensory(5-10)sign and symptom.
• Sensory abnormality in 68-84of patient ,
• primarily affecting large fiber modality
• (vibration ,touch)
• Sensory ataxia, positive Romberg sign ,wide
• base gait may be found.

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• Chronic sensory demyelinating neuropathy only
  sensory
• sign and symptom. however EDX reveal motor nerve
• abnormality.
• Most patient with a demyelinating neuropathy who
  have
• mainly sensory sign and symptom with normal or
  only mild
• distal weakness have an IgM monoclonal gammopathy
  .
• Whenever a pure sensory neuropathy is present ,
• consideration should be given to other diseases
  well, such as
• sjogren syndrome or paraneoplastic neuronopathy,
  both
• associated with sensory ganglionitis.

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• Most patient have areflexia or hyporeflexia.
• Some patient develop dropped head syndrom
  secondary
• to neck extensor weakness.
• Autonomic dysfunction (incontinency , impotency)
  less
• common.
• Respiratory insufficiency reported in 8-15 of
  patient.
• 3-5 of patient have evidence of CNS
  demyelination clinically .
• Patient may developed a myelopathy due to
  compression of spinal
• cord by hypertrophied nerve roots.

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• CIDP like neuropathy
• HIV infection
• Hepatitis
• Inflammatory bowel disease
• DM
• SLE
• Monoclonal gamopathy of uncertain significance
  (MGUS)
• Lymphoma
• Bone marrow and solid organ transplantation
• Paraneuoplastic complication of pancreas and
  colon carcinoma, SCC lung , melanoma,
  cholangiocarsinoma
• Toxic induced neuropathy (procainamide,
  cyclosporine and tacrolimus)

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LAB feature

• An elevated CSF protein is found in 80-95 of
  patient.
• Cell count is usually normal
• .
• WBC CSF should be lt10/mm3
• Elevated CSF cell count should lead to
  consideration of
• HIV infection, lyme, leukemic infiltration of
  nerve root
• Oligoclonal band demonstrated in the CSF in 65
• MRI with gad may reveal hypertrophy and
  enhancement of the nerve root and peripheral
  nerve.

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M-NCV

• CMAP parameter most useful diagnostic
• test in demyelinating process.
• a 50 drop in Ampl or negative peak area
• for define conduction block.
• Increased CMAP Ampl , Increased NCV,
• decreased conduction block, seen in
• association with improvement in strength.
• Clinical improvement primarily result of
• resolving conduction block.

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S-NCV

• gt80 low Ampl or unobtainable SNAP.
• A characteristic finding is abnormal median
• or ulnar SNAP when the sural SNAP are
• normal.
• A similar discrepancy between the upper
• and lower limb SNAP seen in sensory
• ganglinopathy , but the EDX abnormality in
• such cases are axonal , not demyelinating.

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EMG

• Widespread fib and PSW are commonly
• detected in intrinsic foot and hand muscle
• and more proximal muscle.
• The degree of fib and PSW is high during
• an exacerbation with a reduction during
• clinical remission.

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treatment

• Treatment of choice depend on other medical
• problem(avoid IVIG in renal defficiency) and
  accessibility.
• Corticosteroid prednisone 1/5mg/kg per day for
  2-
• 4wk,then switch to alternate-day.
• Functional muscle recovery is first noted in the
• proximal limb muscle.

49

• PE unfortunately response to PE is transient,
  usually
• lasting only a few wk.
• PE used usually in combination with prednisone,
  in patient
• with severe generalized weakness.
• PE used alone in patient in whom we wish to avoid
  long
• term prednisone(poorly controled DM or HIV
  infection) or in
• whom IVIG is contraindicated (renal
  insufficiency).
• Used a trial course of PE in patient who do not
  fulfill all of
• criteria for CIDP or those that have an
  underlying condition
• making the diagnosis difficult(DM and
  superimposed CIDP-
• like neuropathy).

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• IVIG for many authorities , IVIG has become
• the treatment of choice in CIDP.
• A IgA level should be assayed before
• administering IVIG.patient who are IgA
• deficiency due to IgE anti IgA antibody or a
• congenital deficiency may develop anaphylactic
• reaction to IVIG.

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• Azathioprine
• Cyclophosphamide
• Cyclosporine decreased relapse rate in patient
  with the relapsing form of CIDP and improved
  strength and function in those with the chronic
  progressive form.
• Interferon

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prognosis

• Require symmetric,proximal and distal arm and leg
• weakness to diagnose CIDP.
• Patient with mainly sensory symptom, mild distal
  weakness
• or asymmetric motor involvement much less
  responsive to
• specific form of therapy
• Poor long term prognosis progressive course, CNS
  
• involvement and particularly axonal loss.

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CIDP in children

• Commonly present with difficulty in ambulating
• Response to standard form of therapy
• CIDP may be confused with a hereditary neuropathy
  (CMT)
• Family history
• EDX CMT associated with symmetric and diffuse
• involvement of peripheral neuropathy.
• Thus temporal dispersion and conduction block
  are not seen. there is
• usually uniform slowing of conduction velocity
  as well as symmetric
• involvement of proximal and distal segment.
• In contrast , the multifocal nature of CIDP
  result in nonuniform slowing of
• conduction velocity, temporal dispersion and
  conduction block.

54
Para protein related neuropathies (monoclonal
gammopathy) and CIDP

• Although IgG is the most common paraprotein in
  the general population ,IgM is by far the most
  common monoclonal protein in patient with
  peripheral neuropathy.
• IgM-MGUS neuropathy are typically demyelinating
  but can be axonal.
• Demyelinating and axonal neuropathy seem to
  occure similar frequency in IgG and IgA-MGUS
• The IgM neuropathy seem to be less responsive to
  immonotheraphy than IgG and IgA neuropathy.
• At least 50 of IgM group have antibody against
  myelin associated
• glycoprotein.

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• Most patient present with a late onset distal and
  
• symmetric sensorimotor neuropathy.
• Sensory ataxia and tremor were common.
• IgM neuropathy experience more disability related
• to sensory loss. weakness was only a minor
  feature.
• In IgM neurapathy ,NCV more slowing and
• prolongation of distal latency compared with IgG
  and
• IgA.

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• Patient with MGUS-CIDP had a more indolent
• course , more frequent sensory disturbance with
• ataxia and less severe weakness than patient with
  
• idiopathic CIDP.
• no difference in various motor parameters.
• MGUS group had more severe sensory conduction
  abnormality.
• Ig-M subgroup smaller TLI.
• Idiopathic CIDP had a significant improvement
• rate(88) than MGUS CIDP(50)

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Distal acquired demyelinating symmetric
neuropathy (DADS)

• Monoclonal protein detected in 75 cases
• (IgM)
• No significant EDX difference between IgM-DADS,
• idiopathic DADS or CIDP.
• Patient with IgM-DADS neuropathy demonstrated a
• poor response to immunotherapy , whereas patient
  
• with idiopathic DADS and CIDP usually improved
  with
• therapy.

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Multifocal motor neuropathy (MMN) (multifocal
demyelinating neuropathy with conduction block)

• An immune mediate demyelinating
• neuropathy characterized clinically by
• asymmetric weakness and atrophy, typically in
• the distribution of individual peripheral nerve.
• MMN is commonly misdiagnosed as ALS
• however muscle involvement is in the
• distribution of individual peripheral nerves, not
• spinal roots.

59

• Incidence of MMN much less than ALS(1/50)
• M/F3/1
• Age at onset of symptom usually early in fifth
  decade of life.
• Typically, diagnosis is delayed by several years
  because of the slow ,insidious progression and
  misdiagnosis of the disorder.
• Patient develop focal muscle weakness accompanied
  by
• cramps and fasciculation, usually beginning in
  the distal
• Upper limbs.

60

• Patient generally present with intrinsic hand
• weakness ,wrist drop or foot drop.
• Mild sensory symptom have been described
• ,but if there is objective sensory loss, one
  should consider MADSAM neuropathy.

61

• P/E reveals weakness in a multifocal pattern in
  the upper and
• lower limbs, paralleling a peripheral nerve as
  opposed to the
• spinal segmental/root distribution seen in motor
  neuron disease.
• A helpful feature is the lack of atrophy in weak
  muscle group
• early in the course of illness however decreased
  muscle bulk
• can result in time from secondary axonal
  degeneration.
• Sensory exam should be normal.
• MSR variable in unaffected limb, whereas depress
  or absent
• in weak muscle.

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• The observation of fasciculation, weakness and
• essentially preserved sensation is certainly
• suspicious for an anterior horn cell disorder.
• however ,the multifocal peripheral nerve
• involvement ,as opposed to spinal root level of
• dysfunction, combined with sparing of muscle bulk
• point to diagnosis of MMN.

63

• In contrast to CIDP and MADSAM,CSF protein is
  usually normal in patients with MMN.
• Twenty to 80 of MMN have detectable IgM
• antibody direct against gangliosides ,mainly
  GM1but also GM2.
• A high titers the antibodies appear to be rather
  specific for MMN ,but the sensitivity of the test
• is too low.
• The most sensitive and specific test is the NCS.

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EDX

• There is often evidence of conduction block in
  multiple upper and lower limb nerves.
• conduction block is not located at the expected
  common nerve entrapment sites, but in the
  mid-forearm or leg, upper arm, across brachial
  plexus, or nerve root region.
• conduction block may be present not only in
  multiple
• different nerves but also at several location
  along the course
• of the same nerve.
• A reduction in distal CMAP AMPL can be seen in
  chronic
• lesions due to secondary axonal loss.

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• Although motor conduction block has been
  considered the EDX hallmark of MMN, other
  features of demyelination
• (prolonged distal latency, temporal dispersion
  ,slow
• conduction velocity and prolonged or absent
  F-waves) are typically present on motor NCS.
• Diagnosis does not require conduction block if
  other features of demyelination are present.
• SNAP parameters is normal.

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Needle EMG

• Unaffected muscles should demonstrate
• no abnormalities.
• In weak muscle reduced recruitment , fib
• and PSW, fasciculation potential and rarely
• myokymic discharge.
• These abnormalities improve after treatment.

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Treatment

• In contrast to CIDP and MADSAM neuropathy ,few
• patients(lt3)With MMN improve with high doses of
• corticosteroids or PE.
• Intravenous cyclophosphamide was the first
• immunosuppressive agent demonstrated to be
• effective in MMN ,over 70 of reported patients
• improved clinically after treatment.
• IVIG is now the treatment of choice in MMN.
• Not all patients with MMN respond to IVIG. some
  series
• have noted that later age of onset and patient
  who have
• significant muscle atrophy do not respond as well
  to
• treatment.

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Multifocal acquired demyelinating sensory and
motor neuropathy (MADSAM)

• The sign and symptom of MADSAM neuropathy are
  essentially those of mononeuropathy multiplex.
• M/F2/1
• Mean age of onset in the early 50s.
• Onset is usually insidious and slowly progressive
  with initial involvement usually in the upper
  limb.
• Motor and sensory involvement to peripheral nerve
  distribution rather
• than generalized stocking and glove pattern.
• MSR is decreased or absent in a multifocal ,
  asymmetric distribution.

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• CSF protein elevated in 60-80 of patient.
• As with CIDP and MMN ,NCS demonstrate conduction
  block, temporal dispersion, prolonged distal
  latency and F-wave and slow NCV in one or more
  motor nerves.
• SNAP are absent or small AMPL.
• Fib ,PSW and polyphasic ,long duration MUAP.
• In contrast to MMN but similar to CIDP , most
  patient with MADSAM improvement with steroid.
• Most patient improve with IVIG.

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Idiopathic sensory neuronopathy / ganglionopathy

• Believed to be caused by an autoimmune
• attack directed against the dorsal root ganglia.
• DDX of sensory neuronopathy includes
• paraneoplastic syndrome, which is typically
  associated with anti-HU antibody
• Sjogrens syndrome
• Medication or toxins
• Infection agents

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• A slight female predominance,mean age of onset is
  49 Years
• The neuronopathy can present acutely with an
  abrupt onset over a few hours or developed more
  insidiously
• Numbness can begin in face , trunk or limbs.
• Symptoms begin asymmetrically and in the upper
  limb in nearly one-half of patients.
• Usually the sensory symptoms are generalized, but
  they can remain asymmetric.
• Because of the prominent large fiber sensory
  loss, patient describe clumsiness of the hands
  and gait instability.
• Marked reduction in vibration and position sense.

73

• The deficit more impaired in upper limb than
  lower limbs, unlike length-dependent axonal
  neuropathy.
• Pain and temperature are less affected.
• Manual muscle testing usually normal.
• Patient often complain of weakness.
• Sensory ataxia resulting from the loss of
  proprioception

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• Positive Romberg sign
• MSR are decreased or absent.
• Idiopathic sensory neuronopathy is a
• diagnosis of exclusion
• MRI reveal gadolinium enhancement of the
• posterior spinal roots, increased signal
• abnormality on T2 image in the posterior
• columns.

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• Most prominent EDX abnormality is absent or low
  AMPL SNAP.
• Sensory distal latency and NCV normal or mildly
  abnormal.
• DML and MNCV and F-waves usually normal.
• H-reflex and Blink reflex typically absent.
• An abnormal Blink reflex favors a
  nonparaneuoplastic etiology for sensory
  neuronopathy but does not exclude an underlying
  malignancy.
• Needle EMG is usually normal.

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treatment

• PE,IVIG and corticosteroid
• A few patient may improved spontaneously.
• There is no indication to treat a patient
• with a stable deficit

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Idiopathic autonomic neuropathy

• The most common symptom was orthostatic dizziness
  or
• lightheadedness(80)
• GI involvement is the second most common
  symptom(70)(neusea, vomiting diarrhea ,
  constipation and ileus)
• Thermoregulatory impairment with heat intolerance
  and sweating was present in most patient.
• Blurred vision, dry eye and mouth, urinary
  retention and incontinence
• and impotence are often present.
• Muscle strength was normal.
• QSART (quantitative sudomotor axon reflex test)
  score are
• abnormal in 85 of patient.
• Abnormal thermoregulatory sweat test in 12-97

78

• Motor NCS are normal.
• SNCS have normal in most patient. a few patient
• demonstrate reduced SNAP AMPL or slight prolonged
  latency
• SSR response may be absent.
• PE,IVIG and prednisone tried with variable
• success.
• Most important aspect of management is
• supportive therapy for orthostatic hypotension,
• bowel and bladder symptoms.