Symptoms depend on which nerves are damaged. They often affect the feet and sometimes the legs and hands and include muscle weakness and abnormal feelings such as numbness and pins and needles. The abnormal feeling may be painful, like burning or pricking. Symptoms may also include clumsiness and tiredness. The condition may be very mild and cause no or little trouble. However, it can sometimes be severe, causing severe numbness, pain or weakness.
Peripheral neuropathy means disease of the peripheral nerves. The peripheral nerves extend throughout the body reaching the tips of the toes and the fingers. They carry nerve signals from the brain which make the muscles work and to the brain which tell us that what we are touching. They also tell us whether things are smooth or rough and hot, cold or painful.
What are the symptoms?
What are the causes?
There are hundreds of causes of peripheral neuropathy. The most common cause is diabetes (see entry Diabetes Mellitus). About half of people with diabetes get peripheral neuropathy usually causing numbness and sometimes pain in the feet. This is more likely if the blood sugar control is poor. Other causes are:
- lack of particular vitamins
- poisons in the environment
- some drugs
- inflammation of the nerves
- hereditary (affecting more than one member of a family).
In about a quarter of people with peripheral neuropathy no cause is found.
How is it diagnosed?
A doctor will often be able to tell if a person has peripheral neuropathy by listening to their symptoms and doing an examination. If the cause is obvious, for instance in diabetes, the person may not need to see a specialist. If not, they should see a neurologist, (a specialist in diseases of the peripheral nerves and brain). The doctor may conduct blood and urine tests to find out what the cause is. They may also use the following special tests:
- an electromyography (EMG) - where the doctor gives small electrical shocks to the nerves to tell whether they conduct messages properly. This helps to tell whether peripheral neuropathy is present and what type it is.
- a lumbar puncture - where the doctor numbs the lower part of the back and then removes some the spinal fluid from inside the backbone with a needle. Examining the spinal fluid in the laboratory helps to tell what type of peripheral neuropathy is present.
- a nerve biopsy - this is rarely needed. After an injection of anaesthetic a doctor removes a tiny piece of nerve, usually from the outside of the ankle, to examine under the microscope. This helps to show the cause of the peripheral neuropathy.
How is it treated?
The treatment needed will depend on the symptoms a person experiences. If it is weakness they may need:
- exercises prescribed by a physiotherapist.
- splints if their ankles are very weak
- one or two sticks or crutches or a frame to help walking
- very rarely, a wheelchair.
If it is loss of feeling they may need:
- to take great care of their feet to avoid ulcers.
If there is pain, they may be helped by:
- drugs including paracetamol, amitriptyline or nortriptyline, gabapentin or pregabalin, carbamazepine, duloxetine or tramadol
- attending a special pain clinic for a pain management programme.
There are specific treatments for some types of neuropathy:
- diabetic neuropathy: good blood sugar control
- alcoholic neuropathy: not drinking anymore and vitamin B1
- vitamin-deficiency neuropathy: vitamin supplements. The missing vitamin needs to be identified by a doctor
- drug-related neuropathy: stopping the drug responsible
- inflammatory neuropathy: anti-inflammatory treatment with corticosteroids or other drugs
- hereditary neuropathy: no specific treatment is yet available.
Inheritance patterns and prenatal diagnosis
Some cases of peripheral neuropathy are hereditary. If a doctor or neurologist suspects this then they will refer the family to a genetics centre for information and support.
Is there support?
Families can use Contact a Family's freephone helpline for advice, information and, where possible, links to other families.
Contact a Family's web-based linking service can be accessed at community.cafamily.org.uk