Transcript 1362405401_Painful Neuropathy Syndrome, New Treatments

Diabetic painful neuropathy
Dr. Ashok Kumar Das
Diabetic painful neuropathy
This is a definite subset of diabetic
neuropathy and requires more attention
owing to its painful condition, disability and
wide spectrum of clinical syndrome
Diabetic painful neuropathy
Comprises of clinical syndromes like acute
painful neuropathy, chronic sensorimotor
neuropathy, proximal painful symmetrical
motor neuropathy, proximal painful
asymmetrical motor neuropathy (diabetic
amyotrophy) painful diabetic external
ophthalmoplegia, treatment induced insulin
neuritis, hypoglycaemic neuritis and
painful painless leg .
Diabetic painful neuropathy
* Pain is a feature of small fiber neuropathy.
The small fibers also carry autonomic
impulses.
* It seems logical to expect increased
incidence of autonomic denervation in
painful diabetic neuropathies
Diabetic painful neuropathy
Relief of pain is of paramount importance and
obligatory on the part of physician.
But the state of the art of pain relief in this
syndrome is far from satisfactory.
Many modalities of treatment have been
advocated but the arena of therapy is full of
claims and counter claims.
Diabetic painful neuropathy
* These modalities range from simple
analgesic to most modern aldolase reductase
inhibitors
* In the national context, pain relief must be
obtained by simple measures
Clinical types of painful diabetic
neuropathy - 1
Although a rigid classification of painful
diabetic neuropathy is very difficult they may
be grouped under following three major
categories
1. Symmetrical distal painful polyneuropathies
2. Proximal motor neuropathies
3. Focal asymmetrical painful neuropathies
Clinical types of painful diabetic
neuropathy - 2
Symmetrical distal painful polineuropathies
may be grouped as
1.
2.
3.
4.
Small fibre type
Mixed large and small fibre type
Hypoglycaemic neuropathy/insulin neuritis
Mixed distal sensory-motor neuropathy
Clinical types of painful diabetic
neuropathy - 3
Proximal motor neuropathies can be divided
into two groups
1. Symmetrical proximal motor neuropathy
2. Asymmetrical proximal motor neuropathy
- diabetic amyotrophy
Focal asymmetric neuropathies-1
1. Predominantly sensory:
a)
b)
c)
d)
Intercostal Neuropathy
Truncal neuropathy
Thoraco-abdominal radiculopathy
Neuropathy due to involvement of lateral
cutaneous nerve of thigh
Focal asymmetric neuropathies-2
Predominantly motor:
Mononeuritis or mononeuritis
Multiplex which may include a) Ocular neuropathy
b) Femoral neuropathy
c) Sciatic neuropathy
d) Median neuropathy
Diabetic mono-neuropathies
a)
b)
c)
d)
Isolated and multiple mononeuropathies
Cranial moneuropathies
Proximal motor neuropathies
Truncal polyneuropathy
Distal polyneuropathies
a)
b)
c)
d)
Acute sensory neuropathy
Chronic sensory motor neuropathies
Proximal motor neuropathies
Truncal polyneuropathy
Symmetrical distal
polyneuropathies - 1
Small fibre type:
* In small fibre type neuropathy
* Pain and paraesthesis, most commonly of
the lower extremities are the characteristic
symptoms
* Pain - dull, burning, aching, lancinating,
crushing and cramp-like
Symmetrical distal
polyneuropathies - 1
Paraesthesia may manifest as a sensation of
coldness, numbness, tingling or burning
On exam - dysesthesia and calf tenderness
Symmetrical distal
polyneuropathies - 3
* In addition - diminished pain and
temperature perception in the lower
extremity with less involvement of reflex
and position and vibratory sensation
* Autonomic dysfunction most prevalent
Diabetic neuropathic cachexia:
* Outstanding symptoms - weight loss and
severe pain
* Emotional disturbance
* Anorexia
* Impotence
* Mild diabetes
* Simultaneous onset of diabetes and
neuropathy
Painful-painless leg
* Patient experience pain or paraesthesia
* On neurological examination - pain
sensation absent
* Such patients are at greatest risk of painless
injury to the feet
Hypoglycemic neuropathy /
insulin neuritis
* Hypoglycaemia is rare - but treatable
* Usually presents symmetrical motor,
sensory or mixed neuropathies of uncertain
aetiology
* Distal symmetrical symptoms
* More common in nondiabetic patients
subjected to insulin shock therapy
Mixed distal sensory motor
neuropathies
* Usually occur in middle aged and elderly
with type 2 diabetes
There are two entities
1. Subacute proximal neuropathy of insidious
onset
2. Ischaemic mononeuropathy multiplex of
acute onset
Focal asymmetrical diabetic
neuropathy
* Intercostal neuropathy
* Middle aged or older patients
* Present with longstanding diabetes with
abrupt onset of unilateral pain
* Associated with peripheral sensory
neuropathy,weight loss and worsening of
pain at night
* Condition recovers in 3 months
Truncal neuropathy - 1
* Pain in the trunk
* Abdominal bulge causing muscle weakness
* Clinical features suggestive of malignant
disease
* Electromyography reveals correct diagnosis
* Spontaneous and complete recovery
Truncal neuropathy - 2
* Most diabetic with this syndrome are in 5th
or 6th decade of life
* Associated with weight loss, beginning with
the onset of pain
* Denervation of paraspinal muscles present
* Lesion is proximal, either in the nerve roots
or the spinal nerves
Truncal neuropathy - 3
* Spinal cord compression should be
excluded by appropriate investigations
* Caused by ischaemic infarction of nerve
* No pathological evaluation of involved
intercostal nerve has been reported
Truncal neuropathy - 4
* Involvement of lateral cutaneous nerve may
present with sensory disturbance in thigh
* Usually asymmetrical without motor deficit
* Recover spontaneously
Cranial neuropathy
* With the exception of pupillary
sparing,disruption of oculomotor nerve
function – most frequent
* Recovery usually occurs within 6-12 weeks
* Lower cranial nerves can get involved.
* Internuclear opthalmoplegia
Drugs used in painful diabetic
neuropathy - 1
* Non steroidal anti inflammatory agents
* Ibuprofen 600mg four times daily
* Sulindac 200 mg twice daily
Drugs used in painful diabetic
neuropathy - 2
*
*
*
*
Carbamazepine upto 200 mg q 6h
Amitryphyline-fluphenazine combination
Gabapentin 900 mg q 8h
Whereas lignocaine and phenytoin failed to
do so
* Mexiteline 150 mg – 450 mg / day
Drugs used in painful diabetic
neuropathy - 3
Tricyclic antidepressant drugs:
Amitriptyline 50-150 mg at night
* Nortriptyline 50-150 mg at night
* Imipramine 100 mg daily
* Paroxetine 40 mg daily
Other drugs: Capsaicin 0.075% q 6h
Fluphenazine 1 mg/day