Neuropathy is a condition affecting the nervous system, where the nerve fibres become damaged as a result of an injury or disease.
It is often called peripheral neuropathy because it affects the peripheral nervous system. This is the network of nerves that run out from the brain and spinal cord (which together form the central nervous system) and carry impulses to and from the rest of the body, such as the limbs and organs. Peripheral nerves are responsible for the body’s senses and movements.
Because the peripheral nerves transmit signals to so many different parts of the body, the symptoms of neuropathy can vary depending on which nerves are damaged. For example, damage to the nerves leading to the muscles (the motor nerves) can cause muscle weakness or, in more extreme cases, muscle wasting and paralysis.
Some peripheral nerves, called sensory nerves, feed messages (stimuli) to the brain and spinal cord, so you feel certain sensations. For example, when you prick your finger, sensory nerves transmit this information to the brain and you will feel a sharp sensation. Someone with sensory nerve damage may feel numbness rather than pain.
Sometimes people do not know what the underlying cause of their neuropathy is (idiopathic neuropathy), but in most cases the neuropathy is caused by a known condition or injury. A common type of neuropathy is diabetic neuropathy, which is nerve damage resulting from the high blood sugar levels seen in diabetes.
Neuropathy can be short-term, rapid onset (acute), or long-term, slower onset (chronic), and many nerves may be damaged or just one (mononeuropathy).
The causes are broadly grouped as follows:
- The most common cause in the world is leprosy.
- Genetic diseases: Friedreich's ataxia, Charcot-Marie-Tooth syndrome
- Metabolic/Endocrine: diabetes mellitus , Chronic renal failure, porphyria, amyloidosis, liver failure, hypothyroidism
- Toxic causes: alcoholism, drugs (vincristine, phenytoin, isoniazid), organic metals, heavy metals, excess intake of Vitamin B6 (Pyridoxine)
- Fluoroquinolone toxicity: Irreversible neuropathy is a serious adverse reaction of Fluoroquinolone drugs
- Inflammatory diseases: Guillain-Barré syndrome, systemic lupus erythematosis, leprosy, Sjögren's syndrome
- Vitamin deficiency states: Vitamin B12 (Cyanocobalamin), Vitamin A, Vitamin E, Vitamin B1 (Thiamin)
- Physical trauma: compression, pinching, cutting, projectile injuries (i.e. gunshot wound), strokes including prolonged occlusion of blood flow
- Others: shingles, malignant disease, HIV, radiation, chemotherapy
Many of the diseases of the peripheral nervous system may present similarly to muscle problems (myopathies), and so it is important to develop approaches for assessing sensory and motor disturbances in patients so that a physician may make an accurate diagnosis.
Sources include NIH and NHS. Sections of this article are licensed under the GNU Free Documentation License. It uses material from the Wikipedia article on "Peripheral Neuropathy" All material adapted used from Wikipedia is available under the terms of the GNU Free Documentation License. Wikipedia® itself is a registered trademark of the Wikimedia Foundation, Inc.