Routine use of punch biopsy to diagnose small fiber neuropathy in fibromyalgia patients.

Fibromyalgia is a clinical syndrome that currently does not have any specific pathological finding to aid in diagnosis. Therefore, fibromyalgia is most likely a heterogeneous group of diseases with similar symptoms. Identifying and understanding the pathological basis of fibromyalgia will allow physicians to better categorize patients, increasing prospective treatment options, and improving potential therapeutic endeavors. Recent work has demonstrated that approximately 50% of patients diagnosed with fibromyalgia have damage to their small unmyelinated nerve fibers. A skin punch biopsy is a sensitive and specific diagnostic test for this damage as a reduction in nerve fiber density allows for the diagnosis of small fiber neuropathy. Small fiber neuropathy is a disease with symptoms similar to fibromyalgia, but it often has a definable etiology. Identifying small fiber neuropathy and its underlying cause in fibromyalgia patients provides them with a succinct diagnosis, increases treatment options, and facilitates more specific studies for future therapeutics.