Diabetic neuropathy is a serious and common complication of type 1 and type 2 diabetes.
Ocurres over 90% of diabetes people.
Presence of symptoms and or signs of nerve dysfunction in people with diabetes after all other causes have been excluded.
It’s a type of nerve damage caused by long-term high blood sugar levels.
The condition usually develops slowly, sometimes over the course of several decades.
Distal Symmetrical Neuropathy(DSN) most common form of DN.
DSN affects the toes and distal foot, but slowly progresses proximally to involve the feet and legs in a stocking distribution.
It is also characterized by a progressive loss of nerve fibers affecting both the autonomic and somatic divisions, thereby diabetic retinopathy and nephropathy can occur.
Foot ulceration and painful neuropathy are the main clinical consequences of DSPN, linked with higher morbidity and mortality
2. Diabetic neuropathy is a serious and common
complication of type 1 and type 2 diabetes.
Ocurres over 90% of diabetes people.
Presence of symptoms and or signs of nerve
dysfunction in people with diabetes after all other
causes have been excluded.
It’s a type of nerve damage caused by long-term
high blood sugar levels.
The condition usually develops slowly,
sometimes over the course of several decades.
3. Distal Symmetrical Neuropathy(DSN) most common form
of DN.
DSN affects the toes and distal foot, but slowly progresses
proximally to involve the feet and legs in a stocking
distribution.
It is also characterized by a progressive loss of nerve fibers
affecting both the autonomic and somatic divisions, thereby
diabetic retinopathy and nephropathy can occur.
Foot ulceration and painful neuropathy are the main clinical
consequences of DSPN, linked with higher morbidity and
mortality
6. OXIDATIVE STRESS
As mentioned in polyol pathway
However, oxidative stress could be also initiated by autoxidation of glucose and
their metabolites, increased intracellular formation of Advanced Glycation
Endproducts
oxidative stress is caused by enhanced free radical formation due to glucose
metabolism itself and/or deficits in antioxidant defense and it may play a major
role among the putative pathogenic mechanisms of diabetic neuropathy.
7. MICROVASCULAR CHANGES
In clinical and preclinical studies, it was found that in DNP peripheral
perfusion is reduced, not only in the nervous tissue, but also in the skin,
being an important physiological evidence of microvasculature alteration.
As a result, nerve ischemia occurs
Causing electrical instability, progressive nerve loss in proximal and distal
segments
another structural modification related to hyperglycemia is myelin sheath
alteration. The observed demyelinization can be related to Schwann cells
altered capacity to support normal myelin sheath
8. DIAGNOSIS
• Overall muscle strength and tone
• Tendon reflexes
• Sensitivity to touch and vibration
• Filament test. Your doctor will brush a soft nylon fiber (monofilament)
over areas of your skin to test your sensitivity to touch.
• Sensory testing. This noninvasive test is used to tell how your nerves
respond to vibration and changes in temperature.
• Nerve conduction testing. This test measures how quickly the nerves
in your arms and legs conduct electrical signals. It's often used to
diagnose carpal tunnel syndrome.
• Muscle response testing. Called electromyography, this test is often
done with nerve conduction studies. It measures electrical discharges
produced in your muscles.
• Autonomic testing. Special tests may be done to determine how your
blood pressure changes while you are in different positions, and whether
you sweat normally.
9. TREATEMENT
The goals of treatment are to:
• Slow progression of the disease
• Relieve pain
• Manage complications and restore
function
10. Slowing progression of the disease
Consistently keeping your blood sugar
within your target range is the key to
preventing or delaying nerve damage.
Good blood sugar management may
even improve some of your current
symptoms.
11. PHARMACOTHERAPY
Three different agents have regulatory approval in the United States for the treatment
of DNP:
pregabalin (75-150 mg/day), duloxetine (60 mg/day) and tapentadol (100mg/day)
Anticonvulsants-Pregabalin was the first anticonvulsant to receive approval from
the Food and Drug Administration (FDA) for the treatment of DNP
Gabapentin also used. ( 600mg/day)
Antidepressants-Antidepressants represent the first line drugs in DNP management.
Duloxetine, a serotonin and norepinephrine reuptake inhibitor, is rated level A for
efficacy and is approved in the United States for the treatment of this condition.
Venlafaxine, TCA like Amitriptyline, nortriptyline etc.
Opioids- Morphine, Tapendatol
OTHER AGENTS
Lidocaine patch, Capsaicin topical cream (0.025% to 0.075%), Alpha lipoic acid,
Isosorbide dinitrate etc.
12. Final considerations about DNP
treatment:
Diabetic complications can be reduced with improved
blood glucose control and other lifestyle interventions
The medications rated as level A based on their efficacy
are able to reduce pain and improve some aspects of
patients’ quality of life, but are not able to fully
eliminate pain or prevent/revert the neuropathy.
Even their combination does not result in satisfactory
pain control, being the best improvement in pain,
restricted to 50% of relief for the majority of the
patients.