GSE
Peripheral Neuropathy
Causes of nerve damage/inflammation in peripheral
neuropathy (PN)
Numerous factors can cause neuropathies
Neuropathies affect at least 20 million people in the U.S.. All forms of neuropathy involve inflammation as a result of damage from:
Autoimmune diseases.
E.g. Lupus, rheumatoid arthritis and Guillain-Barre syndrome. Some
neuropathies are caused by inflammation resulting from immune system activities,
and can develop quickly or slowly.
Acute inflammatory demyelinating
neuropathy (aka Guillain-Barré syndrome). Can quickly damage motor, sensory, and autonomic
nerve fibers; Most people recover from this syndrome although severe cases can
be life threatening.
Chronic inflammatory demyelinating
polyneuropathy. Usually damages sensory and motor nerves, but
not autonomic nerves; can alternate between remission and relapse.
Acute or chronic multifocal motor
neuropathy. Affects only motor nerves.
Diabetes (Diabetic peripheral neuropathy). More
than 50% of diabetics develop some type of neuropathy to several nerves; nerve
endings slowly die leading to loss of sensation in the feet, legs and hands
which at times can be painful and can lead to weakness and difficulty walking.
Nerve damage may result from impaired ability to utilize glucose for energy.
Toxin exposure.
Can cause
peripheral nerve damage:
Heavy metals. E.g. arsenic, lead,
mercury, thallium; Magnesium deficiency allows heavy metal deposition in the
brain.
Certain medications.
Certain
anti-cancer drugs (especially chemotherapy),anticonvulsants, antiviral agents, and antibiotics.
Environmental toxins
Infections.
the table below lists some
viral or bacterial infections that can cause peripheral neuropathy by
directl y attacking and damaging
sensory nerves, often producing sharp pain.
Viral and bacterial infections can also cause
indirect nerve damage by provoking autoimmune disorders. In
this case, I.S. components attack the neural myelin sheath or axon.
Bacteria / Virus
Associated Disease
Borrelia burgdorferi
(spirochete bacteria)
Lymes Disease - rapidly developing, painful polyneuropathy, often within a few weeks after initial infection by a tick bite.
Corynebacterium diphtheriae
Diphtheria
Mycobacterium leprae/lepromatosis
Leprosy
Varicella-zoster
Shingles - Postherpetic neuralgia occurring after an attack of shingles
Epstein-Barr virus
Epstein-Barr
Inherited disorders.
E.g.
Charcot-Marie-Tooth disease, amyloid polyneuropathy;
Traumatic injury.
Can
sever / crush / compress / stretch peripheral nerves.
Motor
vehicle accidents
Falls
Sports
injuries
Pressure on the nerve.
Can compress nerve fibers:
Slipped disks between vertebrae
Broken/dislocated bones
Using
a cast or crutches / Spending a long time in an unnatural position
Repetitive Stress /Repeating a motion
many times (E.g. typing) - repetitive
flexing of any group of joints for prolonged periods often leads to entrapment
neuropathies, by causing ligaments, tendons, and muscles to become inflamed and
swollen, constricting the narrow passageways through which some nerves pass.
E.g. Carpal tunnel syndrome
A pinched nerve in the back
Tumors.
Growths can form directly on the nerves
themselves, or tumors (malignant and benign) can exert pressure on surrounding
nerves contributing to PN;
Acute and chronic
inflammation of connective tissue. Acute inflammation of protective tissue
surrounding nerves can spread directly into nerve fibers. Progressive
destruction of connective tissue from low level chronic inflammation renders
nerve fibers more vulnerable to compression injuries and infections. Inflamed,
swollen joints can entrap nerves, with ensuing pain.
Vitamin deficiencies
/Alcoholism. Vitamins B1
(thiamine), B3 (niacin),
B6, B12, E
are particularly important to nerve health
and whose deficiency is a factor in PN.
B1
deficiency is typically seen in alcoholics
There are several causes of B12
deficiency:
A strict vegetarian diet. Since animal-based foods such as red meat,
dairy products, fish, poultry and eggs are the only recognized source of dietary
B12.
Inability of stomach acids to aid in
B12 absorption. As such, drugs taken to reduce stomach acid
should be taken with B12 supplements.
Other conditions/procedures associated with a
reduced ability to absorb B12.
Include autoimmune
diseases, pernicious anemia, pancreatic diseases, ileal resection, Crohn's
disease, HIV infection, gastritis, gastric or small intestine surgeries,
malabsorption syndromes, M.S.
Kidney disease, liver
disease. By allowing
abnormally high amounts of toxic
substances in the blood that can severely damage nerve tissue. Most patients on
dialysis because of kidney failure develop polyneuropathy.
Reduced
oxygen supply to
peripheral nerves. Hypoxia caused by
vascular damage or diseases of the blood can seriously damage or kill nerve
tissue. Blood flow is impeded as
blood vessels become inflamed, which reduces lumen size as vessel walls harden,
thicken, and develop scar tissue. Blood vessel constriction is often present with diabetes.
Hormonal imbalances.
Can disturb normal metabolic processes and cause neuropathies.
Underproduction of thyroid hormones (Hypothyroidism).
Slows metabolism, leading to
fluid retention and swollen tissues that can exert pressure on peripheral
nerves.
Overproduction of growth hormone.
Can
lead to acromegaly, a condition where many parts of the skeleton become
abnormally enlarged. Nerves running through enlarged joints can become
entrapped.
Estrogen
neuropathy. In women, neuropathy can start
within a decade of approaching menopause.
Search for: "Estrogen
Neuropathy", "Menopause Neuropathy", "Hypothyroidism Neuropathy"
Gluten sensitivity.
PN may respond to a strict gluten-free diet
M Hadjivassiliou et al,
Sensory ganglionopathy due to gluten sensitivity. Neurology. 2010 Sep
14;75(11):1003-8.
PubMed
M Hadjivassiliou et al,
Neuropathy associated with gluten sensitivity. J Neurol Neurosurg Psychiatry.
2006 Nov;77(11):1262-6. Epub 2006 Jul 11.
PubMed
Therapies for PN