Anti–Plexin-D1 Seropositive Small Fiber Neuropathy: Clinical Phenotype, Demographics, and Literature Review

Abstract

Abstract Objectives: Small fiber neuropathy (SFN) is a subtype of painful neuropathies defined by dysfunction of the Aδ and unmyelinated C fibers. It presents with both neuropathic pain and dysautonomia symptoms, posing a significant diagnostic and therapeutic challenge. To address this challenge, research has been conducted to identify autoantibodies and define their association with phenotypes. Methods: Eleven cases of anti–plexin-D1 seropositive SFN were reviewed, along with relevant literature, in attempt to better define anti–plexin-D1 SFN demographics, symptoms, associated medical conditions, and therapeutics. Results: Anti–plexin-D1 SFN typically presents in female patients, with neuropathic pain, normal skin biopsy findings, and normal nerve conduction studies. Anti–plexin-D1 shows an association with concurrent chronic pain, with almost half of the patients undergoing an interventional procedure. Conclusions: Anti–plexin-D1 represents a unique subgroup of SFN, defined by distinct demographics, phenotype, biopsy findings, and therapeutic management.