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Causes[edit]
There are many possible causes of small fiber neuropathy. The most common cause is diabetes or glucose intolerance.[8] Other possible causes include hypothyroidism, Sjögren's syndrome, Lupus, vasculitis, sarcoidosis, nutritional deficiency, Celiac disease, Lyme disease, HIV, Fabry disease, amyloidosis and alcoholism.[9] A 2008 study reported that in approximately 40% of patients no cause could be determined after initial evaluation.[10] When no cause can be identified, the neuropathy is called idiopathic. A recent study revealed dysfunction of a particular sodium channel (Nav1.7) in a significant portion of the patient population with an idiopathic small fiber neuropathy.[11]

Recently several studies have suggested an association between autonomic small fiber neuropathy and postural orthostatic tachycardia syndrome.[12] Other notable studies have shown a link between erythromelalgia,[13] and fibromyalgia[14]

Small fiber peripheral neuropathy - Wikipedia, the free encyclopedia

Hugs, ElaineD