Diseases & Conditions

Diabetic neuropathy

Many people with diabetes eventually develop some form of nerve damage, a condition known as diabetic neuropathy. High blood sugar can injure nerve fibers throughout your body, but nerves in your legs and feet are damaged most often.

Depending on the affected nerves, symptoms of diabetic neuropathy can range from pain and numbness in your extremities to problems with your digestive system, urinary tract, blood vessels and heart. For some people, these symptoms are mild; for others, diabetic neuropathy can be painful, disabling and even fatal.

Diabetic neuropathy is the most common serious complication of diabetes. Yet you can often prevent diabetic neuropathy or slow its progress with tight blood sugar control and a healthy lifestyle.

Seek medical care if you notice:

• Unusual burning, tingling weakness or pain in your hands or feet
• Dizziness
• Markedly increased or decreased sweating
• Changes in your digestion, urination or sexual function

These symptoms don't always indicate nerve damage, but they may signal other problems that require medical care. In either case, early diagnosis and treatment offer the best chance for controlling symptoms and preventing more-severe problems.

See your doctor immediately if you have a cut or sore on your foot that doesn't seem to be healing, is infected or is getting worse. Even minor sores that don't heal can turn into ulcers. In the most severe cases, untreated foot ulcers may become gangrenous — a condition in which the tissue dies — and require surgery or even amputation of your foot.

Diabetic neuropathy is usually diagnosed based on your symptoms, your medical history and a physical exam. During the exam, your doctor is likely to check your muscle strength and tone, tendon reflexes, and sensitivity to touch, temperature and vibration.

Filament test
Sensitivity to touch is often tested using a soft nylon monofilament. If you're unable to feel the filament on your feet, it's a sign that you've lost sensation in those nerves.

Other tests
In some cases, other tests may be needed, including:

• Nerve conduction studies. This test measures how quickly the nerves in your arms and legs conduct electrical signals. It's often used to diagnose carpal tunnel syndrome.
• Electromyography (EMG). Often performed along with nerve conduction studies, electromyography measures the electrical discharges produced in your muscles.
• Quantitative sensory testing. This noninvasive test is used to assess how your nerves respond to vibration and changes in temperature.

The American Diabetes Association recommends that all people with diabetes have a comprehensive foot exam — either by a doctor or a foot specialist (podiatrist) — at least once a year. In addition, your feet should be checked for sores, cracked skin, calluses, blisters, and bone and joint abnormalities at every office visit.

If you already have diabetic neuropathy, you'll likely be referred to a podiatrist or other specialist for monitoring and treatment.