Neuropathy is a condition related to damage in the nerves of the peripheral nervous system. While it is not regarded as being a disease itself it is often a result of an underlying condition such as cancer, diabetes or liver and kidney problems. It can cause damage to sensory, motor and autonomic nerves and result in a wide range of symptoms. It can be both an acquired and inherited condition. Some of the most common causes of neuropathy include:
Injury or trauma resulting from falls, car accidents and sports injuries can cause nerves to become damaged. Nerve damage can include them being partially or completely severed, crushed, stretched or compressed. Broken bones are also commonly associated with damage to the peripheral nervous system. Slipped discs and carpal tunnel syndrome can also cause nerves to become compressed.
Systemic diseases are those that affect the whole body many of which result in peripheral neuropathy. Nerve tissue is susceptible to a number of conditions including:
It has been estimated that around 60% of diabetes sufferers will go on to develop mild to severe symptoms of neuropathy. Diabetes often has the effect of thickening arteries and so reducing the amount of oxygen that is available for the peripheral nerves which results in damage to them.
Kidney & Liver Disorders
When the kidneys are not functioning properly there can be a build-up of toxic substances in the bloodstream. These substances can have a damaging effect on nerve tissue and polyneuropathy is a common result. Liver conditions can also result in various neuropathies caused by chemical imbalances.
A hormonal imbalance can cause a disruption to the body’s normal metabolic processes. Imbalances that cause fluid retention and swollen tissue can put pressure on nerves causing them to become damaged. An underactive thyroid gland is one of the most common causes of nerve damage.
Vitamin deficiencies related to malnourishment and alcoholism can result in damage to the nerves. The body needs a constant supply of vitamins E, B1, B12, B6 and niacin to maintain a healthy nervous system. It is thought that excessive alcohol consumption and poor dietary habits affects the body’s ability to process these vitamins.
Tumours (both benign and malign) can develop and cause pressure to be exerted on nerves which has a damaging effect on them. They can affect all areas of the body and lead to motor, sensory and autonomic nerve damage.
Viral and Bacterial Infection
Separate from systemic causes are neuropathies caused by bacterial and viral infection. Damage to the nerves can be caused by viral infections such as herpes simplex and herpes varicella-zoster viruses. Viruses typically attack sensory nerves and can result in intense pain for sufferers. HIV can also cause nerve damage. Bacterial infections such as Lyme disease, leprosy and diphtheria can cause extensive damage to the peripheral nervous system. While leprosy and diphtheria are rare in the developed world the number of reported cases of Lyme disease has been increasing steadily for years.
As well as being the result of systemic illness, physical trauma and viral infection peripheral neuropathy can also be an inherited condition.