Small Fiber Neuropathy

Small fiber neuropathy is a condition where the small nerve fibers malfunction. These fibers are the nerve endings located just beneath the skin, responsible for sensing pain and temperature. Additionally, some small nerve fibers connect the brain to various organs, playing a role in autonomic functions. These include unconscious processes such as blood pressure regulation, gastrointestinal activity, and sweating.

Small fiber neuropathy can cause severe and debilitating pain and autonomic dysfunction, significantly impacting quality of life and increasing healthcare costs.

Diagnosis

The diagnosis of small fiber neuropathy cannot be made based on a single (blood) test. Neurological examinations often reveal no abnormalities, as strength, deep tendon reflexes, and vibration sense are typically normal. The diagnosis is established when typical symptoms of small fiber neuropathy are combined with:

• Reduced nerve fiber density in a skin biopsy, and/or
• Abnormal results in temperature threshold testing.

When the diagnosis is confirmed, efforts are usually made to identify an underlying cause, as some causes are treatable. However, in some cases, no underlying condition is found. The mechanisms through which certain conditions damage small nerve fibers are often unclear.

Causes

The most common cause of small fiber neuropathy is diabetes mellitus (diabetes). Other potential causes include:

• Autoimmune disorders
• Vitamin deficiencies
• Hereditary conditions

Treatment

Treatment for small fiber neuropathy primarily focuses on addressing any underlying cause, if identified. When no underlying cause is found, treatment is aimed at managing symptoms. Symptom relief may include:

• Medications to reduce pain
• Pain rehabilitation programs

By addressing symptoms and improving pain management, the goal is to enhance the patient’s quality of life and reduce the impact of the condition.