Ahmed Nabeel, Vigouroux Marie, Ingelmo Pablo
Faculty of Medicine, McGill University, Montreal, QC, Canada.
Faculty of Dentistry, McGill University, Montreal, QC, Canada.
J Pain Res. 2022 Feb 17;15:513-520. doi: 10.2147/JPR.S340038. eCollection 2022.
Juvenile fibromyalgia (JFM) is a condition that presents as chronic widespread musculoskeletal pain and affects children and adolescents. JFM remains a challenging diagnosis, as it is both based on subjective criteria and the pathogenesis is poorly understood. Small fiber neuropathy (SFN) is a distinct condition, which is characterized by pathology of small A-delta and C fibers, and can present similarly to JFM. Small fiber pathology is characterized by reduced intraepidermal nerve fiber density (IENFD) on skin biopsy. Recent studies have found that as many as half of patients with JFM can demonstrate decreased IENFD, in pattern similar to SFN. This phenomenon has been referred to as small fiber pathology. The meaning of these findings was disputed; however, the current consensus remains that fibromyalgia and SFN are distinct conditions. Additionally, among patients with fibromyalgia, there are two phenotypes: those with small fiber pathology and those without. The purpose of this review was to characterize the role assessment of IENFD plays in the clinical context. We conducted a narrative review of pertinent articles pertaining to JFM, SFN and small fiber pathology in fibromyalgia. We concluded that assessment of IENFD should be completed if SFN is suspected either when a patient first presents or in patients who were previously diagnosed with fibromyalgia and SFN is later suspected. Distinguishing between JFM and SFN is important because recommended therapies differ between the two conditions. However, there is no evidence to support the use of skin biopsy to distinguish between the two discussed fibromyalgia phenotypes. More studies are needed to elucidate whether IENFD varies with morbidity and if both fibromyalgia phenotypes vary in their response to different therapeutic regimens.
青少年纤维肌痛（JFM）是一种表现为慢性广泛性肌肉骨骼疼痛的病症，影响儿童和青少年。JFM仍然是一个具有挑战性的诊断，因为它既基于主观标准，其发病机制也了解甚少。小纤维神经病变（SFN）是一种独特的病症，其特征是小A-δ纤维和C纤维的病理变化，并且可能与JFM表现相似。小纤维病理变化的特征是皮肤活检时表皮内神经纤维密度（IENFD）降低。最近的研究发现，多达一半的JFM患者可表现出IENFD降低，其模式与SFN相似。这种现象被称为小纤维病理变化。这些发现的意义存在争议；然而，目前的共识仍然是纤维肌痛和SFN是不同的病症。此外，在纤维肌痛患者中，有两种表型：有小纤维病理变化的和没有小纤维病理变化的。本综述的目的是描述IENFD评估在临床背景中的作用。我们对与JFM、SFN以及纤维肌痛中的小纤维病理变化相关的文章进行了叙述性综述。我们得出结论，如果在患者初诊时怀疑有SFN，或者在先前被诊断为纤维肌痛且后来怀疑有SFN的患者中，都应完成IENFD评估。区分JFM和SFN很重要，因为这两种病症的推荐治疗方法不同。然而，没有证据支持使用皮肤活检来区分所讨论的两种纤维肌痛表型。需要更多的研究来阐明IENFD是否随发病率变化，以及两种纤维肌痛表型对不同治疗方案的反应是否不同。
