Diagnosing Small Fiber Neuropathy

Clinical Examination and Symptoms

According to Ezekiel Fink (UCLA) clinical examinations can find:

• Stocking-glove distribution - issues start from the feet and hands upwards
• Allodynia - touch and mild sensations produce pain
• Hyperalgesia - hypersensitivity to pinpricks
• Reduced sensitivity to pinpricks and heat sensations
• Reduced sensitivity to vibration at the toes
• Motor strength, tendon reflexes, and balance are fine.

Fink reports that SFN can produce a wide variety of symptoms including painful sensations (burning pain, numbness, lancing pain, tingling), dry eyes, dry mouth, orthostatic intolerance, constipation bladder problems, sexual problems, problems sweating, dry, shiny, discolored skin.

Do Your Symptoms Match?

• Check out a Symptom Screening Test for small fiber neuropathy.
• An Easy Way to Tell if You Have Small-Fiber Neuropathy? The Fibromyalgia Symptom Study

Diagnostic Tests [fright][/fright]
According to Neuropathy Commons, a website produced by Anne Oaklander, the researcher and doctor who uncovered the small fiber neuropathy (or polyneuropathy) in fibromyalgia, three types of tests are recommended by the American Academy of Neurology or the European Academy of Neurology: skin biopsy, autonomic function testing and nerve biopsy.

Skin Biopsies

Skin biopsies are safe and easy to do (any MD can do them) but not enough doctors know about them. They require only a small section of skin (3 mm) and leave minimal scarring. The number of small nerves in the biopsy are quantified and compared to norms. Neuropathy Commons contains a list of doctors across the world who perform skin biopsies here.

Autonomic Function Testing

Autonomic function testing includes a battery of tests that determine if your autonomic nerves are functioning properly. The Mayo Clinic lists breathing, tilt table, sweat gland (sudomotor), gastrointestinal and other tests. Quantitative sensory testing can also be done.


Nerve biopsy

Nerve biopsies are older procedures done only at specialized centers.