Fibromyalgia has been a difficult to classify condition with a combination of nerve-like and joint pains. Treatment has been variably successful, and causes few. However, new studies have helped to shed light on this condition and help reclassify a number of patients as having something else altogether.
Three recent studies demonstrated that a number of patients diagnosed with fibromyalgia had another condition: small fibre neuropathy. Small fibre neuropathy is a condition where the small nerves that supply pain (such as burning, stinging or pins and needles), as well as blood vessels and the heart, are damaged by various conditions such as diabetes.
The first study compared 27 patients diagnosed with fibromyalgia with 30 matched controls. After using a test for small fibre neuropathy called a punch skin biopsy, 40% of the patients with fibromyalgia were shown to have a small fibre neuropathy, versus 3% of controls.
Another study of 25 fibromyalgia patients again found more small fibre neuropathy than in healthy controls or patients with depression.
A final study this time of 56 patients with fibromyalgia again found 60% had biopsy evidence of a small fibre neuropathy.
In total, these studies raise the possibility that fibromyalgia patients may well have a different problem, small fibre neuropathy and this is worth exploring and treating.
1. Oaklander AL, Herzog ZD, Downs HM, Klein MM. Objective evidence that small-fiber polyneuropathy underlies some illnesses currently labeled as fibromyalgia. Pain. 2013;154:2310-2316.
2, Üçeyler N, Zeller D, Kahn AK, et al. Small fibre pathology in patients with fibromyalgia syndrome. Brain. 2013;136:1857-1867.
3. Levine T, Lawson V, Levine A, Hackshaw KV, Saperstein D. Presence of small fiber neuropathy in a cohort of patients with fibromyalgia. [abstract]. Arthritis Rheum. 2012;64(Suppl 10):969.