Kelley Mary A, Hackshaw Kevin V
Department of Neurology, Dell Medical School, University of Texas at Austin, 1601 Trinity St, Austin, TX 78712, USA.
Department of Internal Medicine, Division of Rheumatology, Dell Medical School, University of Texas at Austin, 1601 Trinity St, Austin, TX 78712, USA.
Diagnostics (Basel). 2021 Mar 17;11(3):536. doi: 10.3390/diagnostics11030536.
Small fiber neuropathy (SFN) is a type of peripheral neuropathy that occurs from damage to the small A-delta and C nerve fibers that results in the clinical condition known as SFN. This pathology may be the result of metabolic, toxic, immune-mediated, and/or genetic factors. Small fiber symptoms can be variable and inconsistent and therefore require an objective biomarker confirmation. Small fiber dysfunction is not typically captured by diagnostic tests for large-fiber neuropathy (nerve conduction and electromyographic study). Therefore, skin biopsies stained with PGP 9.5 are the universally recommended objective test for SFN, with quantitative sensory tests, autonomic function testing, and corneal confocal imaging as secondary or adjunctive choices. Fibromyalgia (FM) is a heterogenous syndrome that has many symptoms that overlap with those found in SFN. A growing body of research has shown approximately 40-60% of patients carrying a diagnosis of FM have evidence of SFN on skin punch biopsy. There is currently no clearly defined phenotype in FM at this time to suggest whom may or may not have SFN, though research suggests it may correlate with severe cases. The skin punch biopsy provides an objective tool for use in quantifying small fiber pathology in FM. Skin punch biopsy may also be repeated for surveillance of the disease as well as measuring response to treatments. Evaluation of SFN in FM allows for better classification of FM and guidance for patient care as well as validation for their symptoms, leading to better use of resources and outcomes.
小纤维神经病变（SFN）是一种周围神经病变，由小的A-δ和C神经纤维受损引起，导致临床上称为SFN的病症。这种病理情况可能是代谢、毒性、免疫介导和/或遗传因素的结果。小纤维症状可能多变且不一致，因此需要客观的生物标志物进行确认。大纤维神经病变的诊断测试（神经传导和肌电图研究）通常无法检测到小纤维功能障碍。因此，用PGP 9.5染色的皮肤活检是普遍推荐的SFN客观检测方法，定量感觉测试、自主神经功能测试和角膜共聚焦成像作为次要或辅助选择。纤维肌痛（FM）是一种异质性综合征，有许多症状与SFN中的症状重叠。越来越多的研究表明，约40-60%被诊断为FM的患者在皮肤穿刺活检中有SFN的证据。目前FM中尚无明确界定的表型来表明谁可能有或没有SFN，不过研究表明它可能与严重病例相关。皮肤穿刺活检为量化FM中的小纤维病理提供了一种客观工具。皮肤穿刺活检也可重复进行，用于疾病监测以及评估治疗反应。对FM中的SFN进行评估有助于更好地对FM进行分类，为患者护理提供指导，并验证其症状，从而更好地利用资源并改善治疗结果。
