obsolete sodium channelopathy-related small fiber neuropathy https://github.com/monarch-initiative/mondo/issues/5114 https://github.com/monarch-initiative/mondo/issues/6752 https://github.com/monarch-initiative/mondo/issues/6877 https://github.com/monarch-initiative/mondo/issues/7693 https://www.malacards.org/card/hereditary_sodium_channelopathy_related_small_fibers_neuropathy true Orphanet:306577 OBSOLETE. A rare, genetic, peripheral neuropathy disorder due to gain-of-function mutations in voltage-gated sodium channels present in the small peripheral nerve fibers characterized by neuropathic pain of varying intensity (often beginning in the distal extermities and with a burning quality) associated with autonomic dysfunction (e.g. orthostatic dizziness, palpitations, dry eyes and mouth), abnormal quantitative sensory testing, and reduction in intraepidermal nerve fiber density. Large fiber functions (i.e. normal strength, tendon reflexes, and vibration sense) and nerve conduction studies are typically normal. MONDO:0017629