What Is Neuropathy?

Neuropathy is a term that refers to disease or malfunctions of the nerves. Nerves at any location in the body can be damaged from any injury or disease. Neuropathy is often classified mainly according to the types or location of nerves that are affected. Neuropathy can also be classified according to the disease causing it. (For example, neuropathy from the effects of diabetes is called diabetic neuropathy.

Neuropathy

Types of Neuropathy

Peripheral neuropathy:
Peripheral neuropathy is when the nerves outside of the brain and spinal cord are effected These nerves are part of the peripheral nervous system. Accordingly, peripheral neuropathy is neuropathy
that affects the nerves of the extremities — the toes, feet, legs, fingers, hands, and arms.

Cranial neuropathy:
Cranial neuropathy as name suggest , occurs when any of the twelve cranial nerves (nerves that exit from the brain directly) are damaged. specific types of cranial neuropathy are optic neuropathy and auditory neuropathy,trigeminal neuropathy. Optic neuropathy refers to damage or disease of the optic nerve that transmits visual signals from the retina of the eye to the brain. Auditory neuropathy
involves the nerve that carries signals from the inner ear to the brain and is responsible for hearing.Trigeminal neuropathy mean damage to fifth cranial nerve.

Autonomic neuropathy:
Autonomic neuropathy is damage to the nerves of the autonomic nervous system ie. involuntary nervous system. These nerves control the heart and circulation (including blood pressure), digestion, bowel and bladder function, the sexual response, and perspiration. Nerves in other organs may also be affected.

Focal neuropathy:
Focal neuropathy is neuropathy that is restricted to one nerve or group of nerves, or one area of the body.

What Causes Neuropathy?

Nerve damage may be caused by a number of different diseases, injuries, infections, and even vitamin deficiency states.

Diabetes: Diabetes is the condition most commonly associated with neuropathy. The characteristic symptoms of peripheral neuropathy often seen in people with diabetes are sometimes referred to as diabetic neuropathy. The risk of having diabetic neuropathy rises with age and duration of diabetes.
Neuropathy is most common in people who have had diabetes for decades and is generally more severe in those who have had difficulty controlling their diabetes, or those who are overweight or
have elevated blood lipids and high blood pressure.

Vitamin deficiencies: Deficiencies of the vitamins B12 and folate, as well as other B vitamins, can cause damage to the nerves.

Autoimmune neuropathy: Autoimmune diseases such as rheumatoid arthritis, systemic lupus, and Guillain-Barre syndrome can cause neuropathies.

Infection: Some infections, including HIV/AIDS, Lyme disease, leprosy, and syphilis, can damage nerves.

Post-herpetic neuralgia: Post-herpetic neuralgia, a complication of shingles (varicella-zoster virus infection) is a form of neuropathy.

Alcoholic neuropathy: Alcoholism is often associated with peripheral neuropathy. Although the exact reasons for the nerve damage are unclear, it probably arises from a combination of damage to the nerves by alcohol itself along with the poor nutrition and associated vitamin deficiencies that are common in alcoholics.

Genetic or inherited disorders: Genetic or inherited disorders can affect the nerves and are responsible for some cases of neuropathy. Examples include Friedreich's ataxia and Charcot-Marie- Tooth disease.

Amyloidosis: Amyloidosis is a condition in which abnormal protein fibres are deposited in tissues and organs. These protein deposits can lead to varying degrees of organ damage and may be a cause of neuropathy.

Uremia: kidney patients develop Uraemia (a high concentration of waste products in the blood due to kidney failure) can lead to neuropathy.

Toxins and poisons can damage nerves: Examples include gold compounds, lead, arsenic, mercury, some industrial solvents, nitrous oxide, and organophosphate pesticides.

Drugs or medication: commonly seen with various drugs.Certain drugs and medications can cause nerve damage. Examples include cancer therapy drugs such as vincristine (Oncovin, Vincasar), and
antibiotics such as metronidazole (Flagyl), and isoniazid (Nydrazid, Laniazid).

Trauma/Injury: Trauma or injury to nerves, including prolonged pressure on a nerve or group of nerves, is a common cause of neuropathy. Decreased blood flow (ischemia) to the nerves can also
lead to long-term damage. Post traumatic neuropathy mostly seen during roadside accidents.

Tumors: Benign or malignant tumours of the nerves or nearby structures may damage the nerves,directly, by invading the nerves, or cause neuropathy due to pressure on the nerves. A condition called as paraneoplastic syndrome where nerves damage is early feature for the real malignancy.

SYMPTOMS

Regardless of the cause, neuropathy is associated with characteristic symptoms of paresthesias,dysthesias,anesthesia. Although some people with neuropathy may not have symptoms, certain symptoms are common. The degree to which an individual is affected by a particular neuropathy varies in symptoms.

Damage to the sensory nerves is common in peripheral neuropathy. Symptoms often begin in the feet with a gradual onset of paresthesias loss of feeling, numbness, tingling, or pain and progress toward the centre of the body with time. The arms or legs may be involved. The inability to determine joint position may also occur, which can result in clumsiness or falls. Extreme sensitivity to touch can be another symptom of peripheral neuropathy. The sensation of numbness and tingling of the skin is medically known as paresthesia.

The loss of sensory input from the foot means that blisters and sores on the feet may develop rapidly and not be noticed. Because there is a reduced sensation of pain, these sores may become infected and
the infection may spread to deeper tissues, including bone. In severe cases, amputation may be necessary example diabetic foot.

When damage to the motor nerves (those that control movement) occurs, symptoms include weakness, loss of reflexes, loss of muscle mass, cramping, and/or loss of dexterity.

Autonomic neuropathy, or damage to the nerves that control the function of organs and glands, may manifest with a wide variety of symptoms, including:Nausea, vomiting, or abdominal bloating after
meals.Urinary symptoms, such as incontinence, difficulty beginning to urinate, or feeling that the bladder was not completely emptied.Impotence (erectile dysfunction) in men are hall mark features of autonomic neuriopathy Dizziness or fainting. Constipation or diarrhoea is seen in case of autonomic neuropathy. Blurred vision could be the feature of optic nerve involvement. Heat intolerance or  decreased ability to sweat is seen in case of autonomic neuropathy.Hypoglycemia unawareness: it is seen in case of diabetic autonomic neuropathy. Low blood sugar levels (hypoglycemia) are associated with trembling, sweating, and palpitations. In people with autonomic neuropathy, these characteristic symptoms may not occur, making dangerously low  blood sugar levels difficult to recognize.

Dr. Navin Tiwari

Director, Asian Neuro Centre, Indore and Consulting Neurologist with more than 10 years of experience.

We at Asian Neuro Centre offers a comprehensive screening and care program for neuropathic patients.
We have world class machine for nerve study which h give precise result about your nerves.