What’s Causing the Pain?

Solving the mystery of the tingling, numbness, or pain in your feet or hands   -- and the causes—requires a bit of detective work. That's because peripheral neuropathy is not a single disease, but can be caused by a number of conditions that damage or impair the nerves in your extremities. 

Strangely, in as many as 15% of cases, there is no known cause! 

 The Mayo Clinic list of possible causes include (in alphabetical order):

• Alcoholism. Alcoholism can lead to vitamin deficiencies that in turn can damage nerves.
• Autoimmune diseases. Among these are Sjogren's syndrome, lupus, rheumatoid arthritis, Guillain-Barre syndrome, and several other types.
• Diabetes. More than half the people with diabetes develop some type of neuropathy. 
• Exposure to poisons. Toxic substances include heavy metals or chemicals.
• Medications. Certain medications, especially those used to treat cancer.
• Infections. These include certain viral or bacterial infections, including Lyme disease, shingles, Epstein-Barr virus, hepatitis C, leprosy, diphtheria and HIV.
• Inherited disorders. Disorders such as Charcot-Marie-Tooth disease are hereditary types of neuropathy.
• Trauma or pressure on the nerve. Traumas, such as from motor vehicle accidents, falls or sports injuries, can sever or damage peripheral nerves. Nerve pressure can result from having a cast or using crutches or repeating a motion such as typing many times.
• Tumors. Growths, cancerous (malignant) and noncancerous (benign), can develop on the nerves or press nerves. Also, polyneuropathy can arise as a result of some cancers related to the body's immune response. These are a form of paraneoplastic syndrome.
• Vitamin deficiencies. B vitamins — including B-1, B-6 and B-12 — vitamin E and niacin are crucial to nerve health. A lack of these vitamins can be a cause.
• Bone marrow disorders. These include abnormal protein in the blood (monoclonal gammopathies), a form of bone cancer (osteosclerotic myeloma), lymphoma and amyloidosis.
• Other diseases. These include kidney disease, liver disease, connective tissue disorders and an underactive thyroid (hypothyroidism).

Seek medical care right away for unusual tingling, weakness or pain in your hands and feet. An early diagnosis, followed by immediate treatment, offers the best chance for controlling your symptoms and preventing further damage to your peripheral nerves.

Source: http://www.mayoclinic.org/diseases-conditions/peripheral-neuropathy/symptoms-causes/dxc-20204947