Small Fiber Neuropathien

Abstract

Small fibre neuropathies (SFN) are a subgroup of sensory neuropathies in which almost exclusively thinly myelinated A-delta fibres and unmyelinated C-fibres are affected. The typical clinical presentation consists in acral burning pain accompanied by par- and dysaesthesias. Neurological examination as well as standard neurophysiological assessment reveal normal to marginally pathological findings. Special investigation techniques are necessary to detect functional and morphological small fibre impairment. The aetiology of SFN is variable and the patients should be examined carefully with regard to underlying potentially treatable diseases. The most frequent reason for SFN is diabetes mellitus; SFN may also be associated with impaired glucose tolerance. Pain in SFN may be caused by sensitisation of peripheral nociceptors and in a subgroup of patients also by a hereditary sodium channel disease based on mutations in the gene of the voltage-gated sodium channel Nav1.7. These pathophysiological insights may lead to the development of specific SFN analgesics. At present, treatment of idiopathic SFN follows guidelines on the treatment of neuropathic pain in general.©Georg Thieme Verlag KGStuttgart . New York.