[Small fiber neuropathy in systemic autoimmune diseases].

Small fiber neuropathy (SFN) causes damage to small-calibre nerve fibers (unmyelinated C fibers and myelinated A-delta fibers). The symptoms of SFN usually are sensitive including paresthesia, dysesthesia or burning pain, and protopathic deficits, sometimes associated with dysautonomia. The causes of SFN can be classified in six main groups: idiopathic, toxic, metabolic, immunological, infectious and hereditary. In this article, we present the diagnostic approach to SFN, the most common autoimmune aetiologies, as well as elements of their therapeutic management.