Brief summary of peripheral neuropathy

1. Dr. Mukesh Kumar Shukla
Senior Resident
Department of Medicine
Hind Institute Of Medical Sciences

9.  Neuropathy indicates disorder or malfunction of the
nerves.
 It refers to involvement of peripheral nervous system .
 It is a common neurological disorder.

10. 1. Cranial nerves (with the
exception of the second)
2. Spinal nerve roots
3. Dorsal root ganglia
4. Peripheral nerve trunks
and their terminal
branches
5. Peripheral autonomic
nervous system

11.  The overall prevalence is 2.4%;
 It increases to 8% in individuals aged above
55 years.
 Diabetes mellitus is the most common cause
worldwide.
1. Martyn CN, Hughes RA. Epidemiology of peripheral neuropathy. J
Neurol Neurosurg Psychiatry.1997;62:310–8.
2. Medicine and Rehabilitation. Neurology 2009;72(2):185Y192.

12. 1. Is this a peripheral neuropathy?
2. What is its distribution?
3. Which fibers are affected?
4. What is the anatomic pattern?
5. What is the time course?
6. What is the likely etiology?
7. Is there evidence of hereditary neuropathy ?

13.  The initial step is to confirm whether the signs and
symptoms are related to peripheral nerve dysfunction.

14.  Patients may present with positive and/or negative
symptoms.
 The initial symptoms are often intermittent and
examination can be normal.
 In most situations, sensory symptoms precede motor
symptoms.

15.  Positive sensory symptoms
◦ burning,
◦ lancinating pain,
◦ tingling,
◦ pins and needles
◦ walking on cotton wool,
 Negative sensory symptoms
◦ numbness,
◦ difficulty differentiating hot from cold
◦ worsening of balance in the dark

16.  Negative motor symptoms
◦ Wasting
◦ Weakness (difficulty in turning keys in locks, unfasten button, opening
bottles and jars, tripping on rugs or uneven ground.)
• Positive motor symptoms
 Cramps
 Twitching
• In the early stage, weakness is distal.
• Early proximal weakness
 inflammatory neuropathy
 porphyric neuropathy.

17.  Autonomic symptoms
◦ lightheadedness associated with orthostasis,
◦ impotence,
◦ sphincter disturbance,
◦ early satiety or bloating
◦ diarrhea,
◦ constipation,
◦ abnormality of sweating
(hyperhydrosis/anhydrosis)

18.  Patient should be asked regarding location at first involvement
and asymmetry at the onset
 On the basis of distribution, neuropathies can be categorized
into
1. Mononeuropathy,
2. Mononeuropathy multiplex
3. Polyneuropathy

19.  It refers to single peripheral nerve involvement
 Usually occur due to trauma, compression or entrapment.
 The common entrapment neuropathies are
◦ carpal tunnel syndrome,
◦ ulnar nerve entrapment at the elbow
◦ peroneal nerve entrapment at the head of the
fibula.

21.  Refers to the involvement of multiple, separate
noncontiguous peripheral nerves either simultaneously or
sequentially.
 Sometimes, mononeuropathy may aggregate resembling
polyneuropathy.
 Occurs most commonly due to
◦ leprosy and
◦ systemic vasculitis (polyarteritis nodosa, Churg-
Strauss syndrome, rheumatoid arthritis, Sjogren's
syndrome)

22.  Most common variety of neuropathy.
 The nerve fibers are affected in a length-
dependent pattern.
 A majority of these cases occur due to
◦metabolic,
◦toxic or
◦systemic disorders.

23.  In a polyneuropathy, manifestations can be classified as
◦ Small-fiber sensory,
◦ Large-fiber sensory,
◦ Motor
◦ Autonomic

25.  Clinical evaluation is often helpful in categorizing a
neuropathy as
◦ axonal,
◦ demyelinating,
◦ neuronal [dorsal root ganglion (DRG)]
 Most axonal neuropathies follow length-dependent pattern
with sensory symptoms & signs predominating over
motor; distal reflexes are absent.

26. Most demyelinating neuropathies affect
motor & sensory fibers (large fiber >
small fiber) equally & areflexia or
hyporeflexia is more generalized.
DRG lesions involve purely sensory
fibers in a non-length-dependent fashion;
sensory ataxia & generalized loss of
reflexes are usually found.

28.  The is important in categorizing neuropathy.
◦ Acute (<4 weeks),
◦ Sub-acute (4–8 weeks)
◦ Chronic (>8 weeks).

30.  The standard history, physical examination and well planned
battery of investigations serve as general framework to
determine the etiology of neuropathy
 Despite of this, in 25 to 30% of the patients in tertiary referral
centers evaluated by experts, the etiology cannot be
established.

31.  History should include questions regarding
◦ occupation (possibility of toxic exposures to solvents, glues,
fertilizers)
◦ dietary habits (e.g. strict vegan diet)
◦ excessive alcohol intake,
◦ smoking (para-neoplastic disease).
◦ sexual history (HIV, hepatitis C)
 A childhood history of ‘‘clumsiness’’ or poor athletic
performance suggests a hereditary cause

32.  History should focus on illnesses associated with neuropathy,
such as
◦ endocrinopathy (diabetes mellitus, hypothyroidism),
◦ renal insufficiency,
◦ hepatic dysfunction,
◦ connective tissue disorders,
◦ Cancer
 Surgical history should address
◦ bariatric surgery,
◦ multiple orthopedic procedures,
◦ surgeries for ‘‘entrapped nerves.’’

33.  Skin and mucous membranes may demonstrate
◦ Maculo-anesthetic patches with thickened nerves (Leprosy)
◦ purpura, livedo reticularis (vasculitis )
◦ oral ulcers ( HIV),
◦ salivary gland swelling, dry eyes or mouth (sarcoidosis, Sjogren
syndrome),
◦ gum ‘‘lead lines’’ (lead exposure).

34.  Nerve enlargement can be seen in
◦ Leprosy
◦ Heriditary motor and sensory neuropathy
◦ Refsum’s disease
◦ Amyloidosis
 Easy locations to palpate nerves are
◦ the greater auricular nerve
◦ the ulnar nerve
◦ the superficial radial nerve
◦ the common peroneal nerve

35.  Skeletal deformities hammer toes, pes cavus, and
kyphoscoliosis are suggestive of an inherited
polyneuropathy.
 Feet should be specifically examined for signs of trauma
as an insensate foot could be an early indicator of an
impending Charcot foot deformity.

36.  Anosmia (Refsum's disease, vitamin B12 deficiency)
 Optic atrophy (inherited neuropathies,vit B12 deficiency)
 External ophthalmoplegia (Miller Fisher syndrome,
Botulism,Diabetes)
 Trigeminal sensory loss (Sjogren's syndrome)
 Facial weakness (GB syndrome)

37.  Muscle power testing in context of nerve & root distribution
is crucial.
 It should assess muscle bulk, tone, and strength.
 Because most neuropathies cause distal weakness, the
intrinsic foot muscles may be affected first, resulting in
clawed feet and hammer toes.

38.  Approached with nerve anatomy & disease
type in mind.
 Monofilament probes can grade severity of
loss.
 Test modalities that sub-serve
◦ large fibers (vibration, joint position and
Rhomberg’s test)
◦ small fiber (pinprick, pain and temperature)

39.  Ankle hyporeflexia or areflexia is common in large fiber
neuropathy,
 Ankle reflexes are typically preserved with small fiber
neuropathy (SFN). .
 Distal reflex loss are characteristic of length-dependent
axonopathies.

41.  Routine blood investigations:
◦ Blood count
◦ ESR
◦ Blood sugar
◦ Liver and renal function tests
◦ Serum vitamin B12
◦ Thyroid function test
 Blood investigations depending upon suspected etiology
◦ Vasculitis profile
◦ HIV ELISA
◦ Heavy metal screening

42.  Electrodiagnostic studies
◦ EDx studies may be repeated to
monitor disease progression.
◦ These tests are the standard for large
fiber polyneuropathy diagnosis and
are normal in purely SFN.

43.  Bedside autonomic tests:
◦ Blood pressure response to standing (Normal fall: <20/10 mmHg),
◦ HR variation with respiration (normal: ≥15 beats/m, I:E ratio 1.2),

44.  Cerebrospinal fluid (CSF)
◦ useful in CIDP, AIDP and chronic immune-mediated axonal
neuropathies where CSF protein are elevated
Genetic testing – For hereditary causes

45.  Rarely performed now a days
 Primary indication is amyloid neuropathy and
vasculitis
 Should only be performed when NCS is
abnormal
 Sural nerve is the most commonly biopsied
nerve as it is pure sensory nerve

46.  Sometimes used to diagnose small fibre
neuropathy
 Used to measure density of small
unmyelinated fibre
 Density of these fibres are reduced in whom
nerve biopsy and NCS are abnormal

47.  Other tests
◦ chest x-ray or CT-thorax for sarcoidosis;
◦ PET scan or CT of chest, abdomen, and pelvis for malignancy;
◦ Skeletal survey and bone marrow biopsy for lymphoproliferative
diseases
◦ Salivary gland biopsy for Sjogren syndrome;
◦ Endoscopy and duodenal biopsy for celiac disease
◦ MRI may document nerve root enhancement in CIDP, show nerve
root clumping in arachnoiditis, or reveal nerve enlargement in
tumors.

49. Diabetes1 2
Paraproteinaemia2 3
Alcohol misuse1
Renal failure1
Vitamin B-12 deficiency1
HIV infection1
Chronic idiopathic 4
axonal neuropathy
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

50. SJOGREN’S SYNDROME
VIT B12 NEUROPATHY
CISPLATIN
PYRIDOXINE NEUROTOXICITY
FRIEDEREICH’S ATAXIA

51. Heriditary sensory neuropathy
Lepromatous leprosy
Diabetes mellitus
Amyloidosis(early familial&primary)
Tangier disease
Fabry’s disease-pain predomonates
Dysautonomia-riley-day syndrome
HIV & antiretroviral therapy neuropathy

52. Global sensory loss
Carcinomatous sensory neuropathy
Hereditary sensory neuropathy
Diabetic sensory neuropathy
Vacor intoxication
Xanthomatous neuropathy of primary biliary
cirrhosis

53. Immune neuropathies
Heriditary motor sensory neuropathies
Acute intermittent porphyria
Diphtheritic neuropathy
Lead neuropathy
Brachial neuritis
Diabetic lumbosacralplexus neuropathy

54. Acute-pandysautonomia
-botulism
-porphyria
-GBS
-Amiodarone
-vincristine
Chronic-amyloid,diabetes,sjogren’s,HSN
1&3,chagas,paraneoplastic

55. RECURRENT POLYNEUROPATHY
Relapsing CIDP
Porphyria
Refsum’s disease
HNPP
GBS
Beriberi
Toxic neuropathy

56. ◦ Guillain-Barré syndrome
◦ Chronic inflammatory demyelinating
polyradiculoneuropathy
◦ Diabetes mellitus
◦ Porphyria
◦ Osteosclerotic myeloma
◦ Waldenstrom's macroglobulinemia
◦ Monoclonal gammopathy of undetermined significance
◦ Acute arsenic polyneuropathy
◦ Lymphoma
◦ Diphtheria
◦ HIV/AIDS
◦ Lyme disease
◦ Hypothyroidism
◦ Vincristine (Oncovin, Vincosar PFS) toxicity

57.  Treatment of the underlying disorder
◦ Glycemic control for diabetic neuropathy,
◦ Vitamin replacement for B12 deficiency,
◦ Immunosuppression for vasculitis,
◦ Surgery for entrapment neuropathy,
◦ Enzyme replacement for genetic diseases
 Pain management
 Supportive care to protect and rehabilitate damaged tissue.

58.  First line-Lidoderm 5% patch,TCA,Gabapentin
Pregabalin,Duloxetine
 Second line-
Carbamazepine,Phenytoin,Venlafaxine,Trama
dol
 Third line-Mexiletene
 Others-EMLA Cream,Capsaicin

60. case of neuropathy
|
Motor Sensory Autonomic Mixed
|
Focal Multifocal Generalized
|
Proximal or Distal Symmetric or asymmetr
|
UMN features present or not
|
Acute Subacute Chronic
|
Narrow down etiology and go for Edx studies