Small Fiber Neuropathy: Symptoms, Treatment, Causes, and More

Overview

Small fiber neuropathy occurs when the small fibers of the peripheral nervous system are damaged. Small fibers in the skin relay sensory information about pain and temperature. In the organs, these small fibers regulate automatic functions such as heart rate and breathing.

A diagnosis of small fiber neuropathy can be a sign of an underlying health condition, such as diabetes. Often, though, no underlying cause is identified.

This condition causes sensory symptoms such as pain, burning, and tingling. These symptoms often start in the feet and progress up the rest of the body. They may become more severe over time.

Small fiber neuropathy is a type of peripheral neuropathy. Peripheral neuropathies affect the peripheral nervous system. This includes the nerves outside of the brain and spinal cord. With small fiber neuropathy, the narrow nerve fibers of the peripheral nervous system are affected.

Symptoms

Symptoms of small fiber neuropathy can vary. Pain is the most common symptom. Other symptoms include sensations, such as:

  • burning, tingling, or prickling (paresthesia)
  • short bursts of pain
  • loss of sensation

Some sensory symptoms can be caused by external triggers. For instance, some people might experience foot pain when wearing socks or touching bedsheets.

Symptoms can be mild or severe, though early symptoms are often mild. Small fiber neuropathy tends to affect the feet first and progress upward. This is known as a “stocking-and-glove” distribution. At later stages, this condition may affect the hands.

In some cases, small fiber neuropathy disrupts autonomic functions. Autonomic functions are things your body does automatically, such as regulating digestion, blood pressure, and urinary function.

When autonomic nerve fibers are affected, symptoms can include:

  • constipation
  • difficulty sweating
  • dizziness
  • dry eyes
  • dry mouth
  • incontinence
  • sexual dysfunction
  • skin discoloration