There are four main types of diabetic neuropathy. You may have just one type or symptoms of several types. Most develop gradually, and you may not notice problems until considerable damage has occurred.

The signs and symptoms of diabetic neuropathy vary, depending on the type of neuropathy and which nerves are affected.

Peripheral neuropathy

Peripheral neuropathy is the most common form of diabetic neuropathy. Your feet and legs are often affected first, followed by your hands and arms. Possible signs and symptoms of peripheral neuropathy include:

  • Numbness or reduced ability to feel pain or changes in temperature, especially in your feet and toes
  • A tingling or burning feeling
  • Sharp, jabbing pain that may be worse at night
  • Pain when walking
  • Extreme sensitivity to the lightest touch — for some people, even the weight of a sheet can be agonizing
  • Muscle weakness and difficulty walking
  • Serious foot problems, such as ulcers, infections, deformities, and bone and joint pain

Autonomic neuropathy

The autonomic nervous system controls your heart, bladder, lungs, stomach, intestines, sex organs and eyes. Diabetes can affect the nerves in any of these areas, possibly causing:

  • A lack of awareness that blood sugar levels are low (hypoglycemia unawareness)
  • Bladder problems, including frequent urinary tract infections or urinary incontinence
  • Constipation, uncontrolled diarrhea or a combination of the two
  • Slow stomach emptying (gastroparesis), leading to nausea, vomiting and loss of appetite
  • Difficulty swallowing
  • Erectile dysfunction in men
  • Vaginal dryness and other sexual difficulties in women
  • Increased or decreased sweating
  • Inability of your body to adjust blood pressure and heart rate, leading to sharp drops in blood pressure when you rise from sitting or lying down (orthostatic hypotension) that may cause you to feel lightheaded or even faint
  • Problems regulating your body temperature
  • Changes in the way your eyes adjust from light to dark
  • Increased heart rate when you're at rest

Radiculoplexus neuropathy (diabetic amyotrophy)

Instead of affecting the ends of nerves, like peripheral neuropathy, radiculoplexus neuropathy affects nerves in the thighs, hips, buttocks or legs. Also called diabetic amyotrophy, femoral neuropathy, or proximal neuropathy, this condition is more common in people with type 2 diabetes and older adults. Symptoms are usually on one side of the body, though in some cases symptoms may spread to the other side too. Most people improve at least partially over time, though symptoms may worsen before they get better. This condition is often marked by:

  • Sudden, severe pain in your hip and thigh or buttock
  • Eventual weak and atrophied thigh muscles
  • Difficulty rising from a sitting position
  • Abdominal swelling, if the abdomen is affected
  • Weight loss

Mononeuropathy

Mononeuropathy involves damage to a specific nerve. The nerve may be in the face, torso or leg. Mononeuropathy, which may also be called focal neuropathy, often comes on suddenly. It's most common in older adults. Although mononeuropathy can cause severe pain, it usually doesn't cause any long-term problems. Symptoms usually diminish and disappear on their own over a few weeks or months. Signs and symptoms depend on which nerve is involved and may include:

  • Difficulty focusing your eyes, double vision or aching behind one eye
  • Paralysis on one side of your face (Bell's palsy)
  • Pain in your shin or foot
  • Pain in the front of your thigh
  • Chest or abdominal pain

Sometimes mononeuropathy occurs when a nerve is compressed. Carpal tunnel syndrome is a common type of compression neuropathy in people with diabetes.

Signs and symptoms of carpal tunnel syndrome include:

  • Numbness or tingling in your fingers or hand, especially in your thumb, index finger, middle finger and ring finger
  • A sense of weakness in your hand and a tendency to drop things

When to see a doctor

Seek medical care if you notice:

  • A cut or sore on your foot that doesn't seem to be healing, is infected or is getting worse
  • Burning, tingling, weakness or pain in your hands or feet that interferes with your daily routine or your sleep
  • Dizziness
  • 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.

Even minor sores on the feet 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. Early treatment can help prevent this from happening.

Mar. 06, 2012