1_ introduction of peripheral neuropathy 2- gullian barre syndrome

1. Peripheral Neuropathy
Mohamed rizk khodair
Lecturer of neurology
october 6 university
Mohamedrizk.med@o6u.edu.eg

2. Neuropathy
is defined as a disease or injury of the peripheral sensory, motor, or autonomic nerves.
It is inflammation and degeneration of the peripheral nerves and/or the cranial nerves resulting in impairment of the
conductivity of these nerves.
It is usually divided into three categories:
1. Injury to the axon's cell body (neuropathy)
2. Injury to the nerve roots distal to their origin (radiculopathy)
3. Injury to the brachial or lumbosacral plexus (plexopathy)

3. Classification
1) According to number of nerves affected:
a) Mononeuropathy: Damage to a single peripheral nerve due to local cause as entrapment or trauma. Carpal tunnel syndrome is the best
example.
b) Mononeuropathy multiplex: Multiple focal nerve injuries, OR two or more isolated nerves in one limb are affected. The commonest causes
are diabetes mellitus, leprosy, amyloidosis, Vasculitis.
c) Polyneuropathy: Affection (symmetrically) of multiple peripheral nerves throughout the body at the same time.
2) According to the function of nerves affected:
a) Motor neuropathy: as lead; GBS, Diphtheritic and peroneal muscular atrophy.
b) Sensory neuropathy: as alcoholic; diabetic; leprotic and nutritional neuropathy.
c) Autonomic neuropathy: as amyloidosis; porphyria and diabetes mellites
d) Mixed sensorimotor neuropathy: as diabetic neuropathy
3) According to temporal evolution of affection:
a) Acute: (days up to 4 weeks), e.g., GBS, vasculitis.
b) Subacute: (4–8 weeks), e.g., sarcoidosis, vitamin deficiency, heavy metal poisoning and toxic neuropathy
c) Chronic: (> 8 weeks), e.g., CIDP (chronic inflammatory demyelinating polyneuropathy), inherited neuropathies, metabolic neuropathies

4. 4) According to an etiology:
a) Heridofamilial neuropathy: as Peroneal muscular atrophy, Refsum’s diseases, Porphyria, Multifocal motor
neuropathy.
b) Acquired neuropathy: as post infective (GBS), infective (Diphtheritic), toxic (alcoholic; arsenic; lead); nutritional
(vitamin B12 deficiency); drug toxicity (isoniazid, vincristine); endocrinal and metabolic (diabetes, hypothyroidism,
uremia); Vasculitis (SLE, polyarteritis nodosa)
5) According to symmetrical affection
as diabetic polyneuropathy, thyroid disease (either hypo or hyperthyroidism), collagen vascular diseases,
sarcoidosis, and critical ill polyneuropathy.
6) According to associated cranial nerve affection:
Neuropathy with cranial nerve involvement: (most often the facial nerve) as Lyme disease, HIV, CIDP,
sarcoidosis, malignant infiltration.
7) According to the pathogenesis:
a) Axonal neuropathy: as Diabetes mellites, Thyroid diseases, Toxic, Vitamin deficiency, SLE, Paraneoplastic
b) Demyelinating neuropathy: as Hereditary, GBS, CIDP
c) Mixed axonal and demyelinating neuropathy.

5. Classification of nerve fibers in peripheral nerves
Fiber class Fiber type fiber size functional class fiber dysfunction
Myelinated nerve
fibers
Large fibers
Aa motor
Neurons
12-20mm
Motor Weakness, atrophy,
cramp, fasciculations
Ab fibers
5-15mm
Sensory Abnormal
proprioception, vibration,
and touch sensation
Small fibers
Ad fibers
3-8mm
Sensory Deep and lancinating
pain, abnormal cold and
pressure sensation
Unmyelinated
Nerve fibers
Small fibers
C fibers
0.2- 1.5mm
Sensory Burning pain and
abnormal heat sensation
C fibers
0.2- 1.5mm
Autonomic Abnormal sweating,
bowel, bladder and
sexual function,
abnormal blood pressure
control

6. Causes
3) Infectious:
Leprosy, Diphtheria, CMV, Campylobacter Jejuni, AIDS; And
Lyme Disease.
4) Neoplastic and para neoplastic syndrome:
Myeloma, and Lymphoma
5) Metabolic and Endocrinal:
DM, Chronic renal failure, Hypothyroidism &Acromegaly.
6) Toxicity:
Alcohol, Lead, Heavy metals: mercury, thallium.
7) Drug induced:
Vincristine, INH, Ethambutol, Lithium, Phenytoin, Metronidazole
8) Vitamin deficiency: Bl, B6, B12, Vitamin E deficiency.
1) Hereditary:
• Hereditary motor and sensory neuropathies (4 types).
• Hereditary sensory and autonomic neuropathies
• Hereditary neuropathy with liability to 'pressure palsy.
• Hereditary neuropathies due to a metabolic defect.
• Others; neuroacanthocytosis, Friedreich' ataxia, mitochondrial.
• 2)Immune mediated:
• Acute idiopathic polyneuropathy "Guillain barre syndrome’.
• Miller Fisher syndrome.
• Chronic inflammatory demyelinating neuropathies.
• Vasculitis.
• Rheumatological diseases: as Sjogren's syndrome, rheumatoid, SLE,
polyarteritis nodosa.

7. General clinical picture of neuropathies
A) Motor manifestations:
 Disease is bilateral and symmetrical.
 Weakness is distal more than proximal, flexors equal to extensors, and abductors equal to
adductors.
 Manifestations of LMNL: atrophy, hypotonia, hypo or areflexia.

8. B) Sensory manifestations:
• Pain (burning) and paresthesia
(tingling and numbness).
• Decreased sensations; superficial
(glove and stoking hypoalgesia) and
deep (Vibration sense lost at medial
malleolus and intact at ASIS).
Modality Superficial
sensation
Deep sensation
Irritative Pain –
temperature
affection,
burning
sensation
Tingling
Destructive Hypothesia
Decrease
sensation to
pain and
temperature
Numbness,
sensory ataxia
+ve Romberg sign

9. C) Cranial nerves: 7, 9, 10, 3 in order.
D) Gait:
 High steppage gait due to weakness (foot drop).
 Stamping gait due to deep sensory loss.
E) Trophic changes:
 ulcers, thin skin, brittle nails may be present.
 Thickened nerves may be present e.g., leprosy.
F) Autonomic manifestations
- More frequent in diabetic polyneuropathy
- Includes: Liability of blood pressure; Light headedness or “dizziness”; Blurred vision; Dry eyes, dry
mouth; Cold feet, trophic ulcers; Pallor or cyanosis of hands & feet; Early satiety, constipation, diarrhea;
Urinary retention, incontinence; Erectile Dysfunction; Hypohidrosis, loss of hair
G) No sphincteric manifestation.

10. Investigations
1)Nerve Conduction Velocities:
In Demyelinating neuropathies:
 Myelin sheath is responsible for conduction of the nerve impulse.
 Demyelinating neuropathies ~ marked decrease of nerve conduction velocity
 (NCV) and prolonged distal latency
 Delayed F wave in radiculopathy.
Axonal neuropathies:
 Normal or-slight decrease in NCV.
 Decreased amplitude of the motor unit potential (MUP).
 EMG: Neurogenic pattern
- At rest: fibrillations, positive sharp waves.
- Minimal contraction: polyphasic action potentials,
increased duration, and increased amplitude.
- Maximal contraction: incomplete interference pattern.

11. 2) Nerve biopsy (Diagnostic)
3) Laboratory investigations.
- Hematology: FBC, ESR, B12, folate.
- Biochemistry: renal and liver function, Ca, fasting glucose, HbA1c immunoglobulins, and protein electrophoresis.
- Immunology: ANA, dsDNAAntineuronal antibodies, hepatitis B, C, cryoglobulins, complement C 3, C4, c-ANCA, p-ANCA.
4) Genetic testing: for certain hereditary diseases.(Chromosome 17 duplication for CMT, Connexin 32, familial amyloid polyneuropathy (FAP) mutations.)
5) Others: CT scan, to detect the cause, CSF.
A)Specific antibody tests:
- GQ1b (Miller Fisher syndrome), anti-MAG (IgM paraproteinemic neuropathy).
B) Radiology
- as MRI brachial, lumbosacral plexus with gadolinium (CIDP, infiltration).
C) CSF examination:
- Should be considered in any progressive undiagnosed neuropathy.
- ↑CSF protein, pleocytosis, oligoclonal bands indicate demyelination or inflammatory process.
- Cytology examination for malignant cells.

12. GUILLAIN–BARRÉ SYNDROME
Acute inflammatory demyelinating poly-radiculo-neuropathy (AIDP)
Guillain-Barré syndrome refers to a group of immune-mediated disorders targeting the peripheral nerves.
The most common form of Guillain-Barré syndrome, acute inflammatory demyelinating polyradiculoneuropathy
(AIDP), accounts for 85–90% of cases. It is caused by an inflammatory reaction in the myelin sheaths of nerve
roots and peripheral nerves.

13. Etiology
 Age: peak incidence at middle age.
 Sex: slightly males more than females (1.5: 1).
 Preceding event (2/3): (1 to 4 weeks) before onset.
1. Viral upper Respiratory tract infections by CMV and others, as influenza, mycoplasma, EB, polio.
2. GIT infections: by campylobacter jejuni (isolated from stool cultures and precede axonal pure motor form
(AMAN).
3. Humoral immunity with antibodies production to myelin component.
4. Surgery or Immunization

14. Pathogenesis
It has been demonstrated that immunological
cross-reactions can occur between microorganism
components and peripheral nervous system
components. An important factor here is the
similarity between lipopolysaccharides of
Campylobacter strains and gangliosides present in
peripheral nerves. Host factors are also very likely
to play a role, as not everyone contracts GBS
following an infection with a particular
Campylobacter strain and the severity of the
disease can vary so much from one patient to
another.

16. Clinical Picture
(Relatively Symmetrical Areflexic Tetra-Paresis)
1) Motor features: Ascending march
 Progressive weakness over 1 day or more (up to 3 weeks).
 Weakness is bilateral and symmetrical, (lower limbs more than upper
limbs).
 Weakness is more distal, or proximal or equal.
 Usually starts in the lower limbs, upper limbs, trunk, and respiratory
muscles.
 It is of LMN type with marked hypotonia and areflexia.
 Others: positive stretch sign, and tender calf muscles.

17. 2) Sensory manifestations:
 In 75%, paresthesias mainly in the toes, is first presentation.
 Severe pain in the calf muscles, back and buttocks.
 Mild glove and stocking sensory loss (impaired vibration and position sensation).
 Sensory loss on central part of the trunk (paraumbilical hypesthesia).
3) Cranial nerve lesions: in 50% of cases.
 Commonest is bilateral facial paralysis.
 2nd common is bulbar, muscles of mastication.
 Rarely ocular nerves are affected.
 Papilledema is rare, usually associated with cranial nerve paralysis because of protein in CSF occlude its
drainage.
 Optic neuritis (uncommon).

18. 4) Severe respiratory affection occurs in 25% of
cases, orthopnea, tachypnea.
5) Autonomic dysfunction: includes sympathetic
or parasympathetic:
 Cardiac arrhythmias.
 Blood pressure and pulse abnormalities in
attacks.
 Facial flushing, iridoplegia and anhydrosis.
 Paralytic ileus.

20. Investigations
1) Lumber puncture and CSF analysis:
 CSF proteins are markedly increased up to 2 gm/L (20-40mg).
 Normal or mild increase in cells.
 This is called cytoalbuminous dissociation (may be normal in 1st
few day).
2) Nerve conduction study and EMG:
 Appear few weeks from onset.
 Demyelinating type: shows delayed distal latency, decreased
conduction velocity, evidence of conduction· block, and absent or
prolonged F wave.
 Axonal type shows normal conduction velocity with decrease
amplitude of MUP.

21. 3) Studies to exclude other conditions:
 Urine porphobilinogen and delta-aminolaevulinic acid levels.
 Antinuclear factor.
 HIV testing in at risk subjects.
 Drugs and toxins screen.
4) General medical studies: Urine Analysis, CBC, ESR, Biochemical Screening, ECG, Chest Radiograph.
5) Studies for underlying pathogenesis:
 Stool culture and serology for C jejuni, and poliovirus (in pure motor syndromes).
 Acute and convalescent serology for cytomegalovirus, Epstein-Barr virus, and mycoplasma pneumoniae.
 Antibodies to gangliosides GMl, GDla, and GQlb.

22. Treatment
1) General Measures:
 Hospitalization and ICU admission if there is respiratory affection.
 Feeding by Ryle tube.
 Elastic stockings and heparin to guard against DVT.
 ECG monitoring and B-blockers for arrhythmias and hypertension.
 Nursing care and physiotherapy and careful limb positioning.
 Guide against exposure keratitis.
2) Plasma exchange:
 It shortens the course with decrease time needed for improvement.
 It decreases the need for ventilation.
 Indications: inability to walk, respiratory or bulbar muscles affection.
 Timing: started in the 1st week, not of value after 2 weeks.
 Better results with demyelinating type.

23. 3) Immunoglobulins: 0.4 gm/kg/ day by I.V infusion for 5 days.
Advantages:
 Immediately available. 4. No risk of circulatory disturbances.
 No cannulation.
 More effective in AMAN.
 Fewer side effects.
NB: Corticosteroids has no benefit.

24. Thank you
Mohamedrizk.med@o6u.edu.eg