2. Generalized term including disorders of any
cause affecting PNS
May involve sensory nerves, motor nerves, or
both
May affect one nerve (mononeuropathy),
several nerves together (polyneuropathy) or
several nerves not contiguous
(Mononeuropathy multiplex)
3. Further classified into those that primarily
affect the cell body (e.g., neuronopathy or
ganglionopathy), myelin (myelinopathy), and
the axon (axonopathy)
4. Disease
Diabetes1 2
Paraproteinaemia2 3
Alcohol misuse1
Renal failure1
Vitamin B-12 deficiency1
HIV infection1
Chronic idiopathic
axonal neuropathy4
Prevalence
11-41% (depending on
duration, type,and
control)
9-10%
7%
4%
3.6%
16% (depending on the
population studied,
usually much lower)
10-40% of different
hospital series
BMJ 2010:341:c6100
5. Loss of function
“- symptoms”
Disordered function
“+ symptoms”
Sensory
“Large Fiber”
↓ Vibration
↓ Proprioception
Hyporeflexia
Sensory ataxia
Paresthesias
Sensory
“Small Fiber”
↓ Pain
↓ Temperature
Dysesthesias
Allodynia
The clinical response to sensory nerve injury
6. Loss of function
“- symptoms”
Disturbed function
“+ symptoms”
Motor nerves
Large fibre
Wasting
Hypotonia
Weakness
Hyporeflexia
Orthopedic deformity
Fasciculation
Cramps
The clinical response to motor nerve injury
7. Loss of function
“- symptoms”
Disturbed function
“+ symptoms”
Autonomic nerves ↓ Sweating
Hypotension
Urinary retention
Impotence
Vascular color changes
↑ Sweating
Hypertension
The clinical response to autonomic nerve injury
8.
9. By far the majority of the toxic, metabolic and
endocrine causes
NCVs: CMAPs ↓ 80% lower limit of normal w/o or
min velocity or distal motor latency change.
Legs>> arms.
EMG: Signs of denervation (acute, chronic) and
reinnervation
10. Unusual by comparison with axonopathies
Clues: hypertrophic nerves on exam
global arreflexia
weakness without wasting
motor >> sensory deficits
NCS can discriminate inherited from
acquired
NCS: Distal motor latency prolonged (>125%
ULN)
Conduction velocities slowed (<80% LLN)
May have conduction block
EMG: Reduced recruitment w/o much
denervation
17. ?MONONEUROPATH
Y
Focal involvement
of a single nerve
Weakness &
sensory loss in the
territory of a single
peripheral nerve
Pain along the
pathway of the
nerve
Direct
trauma
compressio
n
entrapment Vascular
lesions
neoplasms
18. Random pattern of nerve involvement
In distribution of separate
nerves,asymmetric
May/may not be painful
Not length dependent
Isolated reflex loss
CAUSES—inflammatory-leprosy,sarcoid
Vascular-Diabetes
Pressure,Trauma,Infiltration
Vasculitis-
PAN,SLE,RA,scleroderma
Immune-vaccination
19. MC type –Distal symmetric polyneurpathy
Burning sensation,tingling,numbness
Length dependent pattern
Starts in feet,distal stocking glove pattern
Fairly symmetric
Symmetrically decreased reflexes
Sensory>motor
20. Diabetes mellitus
Alcohol
Vit B12 deficiency
HIV
Although more than
one nerve involved
one will be prominant
22. ?POLYRADICULOPATHY
Disease of multiple peripheral nerve roots
Asymmetric with erratic distribution-proximal in
one,distal in another
Pain is a common feature
?MONORADICULOPATHY
Root disease by disease of spinal column
Changes in distribution of spinal nerve root
23. ?SENSORY NEURONOPATHY
Ganglion cells predominantly affected
Both proximal & distal involvement
Sensory ataxia is common
No weakness
But awkward movement d/t sensory disturbances
?MOTOR NEURONOPATHY
Disorder of ant horn cells
Weakness,fasciculation,atrophy
Not properly a process of peripheral NP
24. ?PLEXOPATHY
Asymmetric
Painful onset
Multiple nerves in a single limb
Rapid onset of weakness,atrophy
Isolated reflex loss
37. The temporal course of a neuropathy varies,
based on the etiology.
◦ With trauma or ischemic infarction, the onset will
be acute, with the most severe symptoms at
onset.
◦ Inflammatory and some metabolic neuropathies
have a subacute course extending over days to
weeks.
◦ A chronic course over weeks to months is the
hallmark of most toxic and metabolic
neuropathies.
38. A chronic, slowly progressive neuropathy over
many years occurs with most hereditary
neuropathies or with chronic inflammatory
demyelinating polyradiculoneuropathy (CIDP).
Neuropathies with a relapsing and remitting
course include CIDP, acute porphyria,
Refsum's disease, hereditary neuropathy with
liability to pressure palsies (HNPP), familial
brachial plexus neuropathy, and repeated
episodes of toxin exposure.
39. Ischemic neuropathies often have pain as a
prominent feature.
Small-fiber neuropathies often present with
burning pain, lightning-like or lancinating
pain, aching, or uncomfortable paresthesias
(dysesthesias).
40. Dying-back (distal symmetric axonal)
neuropathies initially involve the tips of the
toes and progress proximally in a stocking-
glove distribution.
41. Peripheral neuropathy can present as restless
leg syndrome.
Proximal involvement may result in difficulty
climbing stairs, getting out of a chair, lifting
and bulbar involvement can also be seen
42. The clinical assessment should include:
◦ careful past medical history, looking for systemic
diseases that can be associated with neuropathy,
such as diabetes or hypothyroidism.
43. All patients should be questioned regarding
◦ HIV risk factors
◦ diet (nutrition)
◦ vitamin use (especially B6)
◦ possibility of a tick bite (Lyme disease)
◦ Constitutional symtoms (malignancy)
45. A cranial nerve examination can provide
evidence of mononeuropathies.
Funduscopic examination may show
abnormalities such as optic pallor, which can
be present in leukodystrophies and vitamin
B12 deficiency.
47. Cardiovagal
◦ Heart rate variability
Adrenergic
◦ Valsalva maneuver
Induces BP changes and monitors pulse reaction
Postganglionic sudomotor function
◦ QSART
48. Screening laboratory tests may be
considered for all patients with DSP (Level
C).
Tests with the highest yield of abnormality:
1. blood glucose (fasting)
2. serum B12 with metabolites
(methylmalonic acid, homocysteine)
3. SPEP(serum protein electrophoresis)
(Level C).
49. ANA, RF, Anti-dsDNA, Anti-Ro, Anti-La,
ANCA screen, cryoglobulins
Urine for heavy metals, porphyrins
IFE/urine IFE/ plasma light chain analysis
50. BLOOD
TC,DC,ESR
Urea,electrolytes,LFT
RBS,HbA1C
Serum protein electrophoresis
Auto Ab=ANA,Antiganglioside,Antineuronal
Vit B 12 level
DNA analysis=chr 17 duplication-HMSN1&1A
=chr 17 deletion -HLPP
51. URINE
BJ protein
Porphyria
Heavy metals
CSF ANALYSIS
NERVE CONDUCTION STUDY
Variation in axonal,demyelinating neuropathy
Conduction block-CIDP,GBS,MMN
EMG-muscle denervation changes
Sensory threshold
Thermal & vibration threshold
52. Antibodies against Gangliosides
GM1 : Multifocal motor neuropathy
GM1, GD1a : Guillain-Barré syndrome
GQ1b : Miller Fisher variant
Antibodies against Glycoproteins
Myelin-associated glycoprotein : MGUS
Antibodies against RNA-binding proteins
Anti-Hu, antineuronal nuclear antibody 1: Malignant
inflammatory polyganglionopathy
53. (1) Confirming the presence of neuropathy,
(2) Locating focal nerve lesions,
(3) Nature of the underlying nerve pathology
56. The limitations of EMG/NCS should be
taken into account when interpreting the
findings.
◦ There is no reliable means of studying proximal
sensory nerves.
◦ NCS results can be normal in patients with small-
fiber neuropathies
◦ Lower extremity sensory responses can be absent
in normal elderly patients.
EMG/NCS are not substitutes for a good
clinical examination.
57. IMAGES
CXR-sarcoidosis,malignancy
Skeletal survey-multiple myeloma
Screening for malignancy
AUTONOMIC FUNCTION TESTS
Diagnostic tests imp in
Asymmetric,motor
predominant,rapid onset,demyelinating
neuropathy
59. In vasculitis, amyloid neuropathy, leprosy, CIDP,
Inherited disorders of myelin, and rare
axonopathies
The Sural nerve is selected most commonly
The superficial peroneal nerve – alternative;
:advantage of allowing simultaneous biopsy of
the peroneus brevis muscle through the same
incision.
This combined nerve and muscle biopsy
procedure increases the yield of identifying
suspected vasculitis
60. “For symptomatic patients with suspected
polyneuropathy, skin biopsy may be
considered to diagnose the presence of a
polyneuropathy, particularly SFSN.”
61. Slow progression
◦ Treat causative factors if possible
◦ If rapidly progressing
IVIG
Immunomodulating agents
Symptom Management