Abstract：
BACKGROUND: Small fiber neuropathy [SFN] is a common peripheral neurologic disorder with a vast array of implicated etiologies. It has previously been proposed that some forms of immune-mediated small fiber neuropathy are driven by vasculitis, though antinuclear cytoplasmic antibodies [ANCA] antibodies have not commonly been reported in association with SFN, thus far. We present this case series to discuss the observation of a possible novel association between ANCA and SFN.
METHODS: This is a retrospective case series of 6 patients with SFN and ANCA positivity, with and without systemic manifestations. Patients included were diagnosed with SFN by skin biopsy or autonomic function testing and were seropositive for ANCA by ELISA.
RESULTS: Six patients are outlined, including 4 females and 2 males. Antigen specific antibodies were MPO alone in 4 cases, PR3 alone in 1 case and both MPO and PR3 in 1 case. Systemic vasculitis was noted in 2 patients. Five patients received immunosuppression. Three patients experienced partial improvement, while symptoms stabilized in 3 patients.
CONCLUSIONS: This is the first series of patients with suspected immune-mediated SFN and ANCA antibody positivity, raising the possibility of ANCA mediated isolated SFN. This is in contradistinction to the more typical ANCA-mediated peripheral neuropathy manifestations of mononeuropathy multiplex or axonal sensorimotor neuropathy. We cannot unequivocally prove ANCA-associated vasculitis [AAV] causality in these cases; however, the stabilization in SFN symptomatology and associated improvement in ANCA antibody titer, after AAV treatment, may be indicative of an association.
METHODS: This is a retrospective case series of 6 patients with SFN and ANCA positivity, with and without systemic manifestations. Patients included were diagnosed with SFN by skin biopsy or autonomic function testing and were seropositive for ANCA by ELISA.
RESULTS: Six patients are outlined, including 4 females and 2 males. Antigen specific antibodies were MPO alone in 4 cases, PR3 alone in 1 case and both MPO and PR3 in 1 case. Systemic vasculitis was noted in 2 patients. Five patients received immunosuppression. Three patients experienced partial improvement, while symptoms stabilized in 3 patients.
CONCLUSIONS: This is the first series of patients with suspected immune-mediated SFN and ANCA antibody positivity, raising the possibility of ANCA mediated isolated SFN. This is in contradistinction to the more typical ANCA-mediated peripheral neuropathy manifestations of mononeuropathy multiplex or axonal sensorimotor neuropathy. We cannot unequivocally prove ANCA-associated vasculitis [AAV] causality in these cases; however, the stabilization in SFN symptomatology and associated improvement in ANCA antibody titer, after AAV treatment, may be indicative of an association.
摘要：
背景：小纤维神经病[SFN]是一种常见的周围神经疾病，有大量的相关病因。以前已经提出，一些形式的免疫介导的小纤维神经病是由血管炎引起的，虽然抗核细胞质抗体[ANCA]抗体通常没有与SFN相关的报道，到目前为止。我们提出这个案例系列来讨论ANCA和SFN之间可能的新关联的观察。
方法：这是6例SFN和ANCA阳性患者的回顾性病例系列，有和没有系统性表现。包括的患者通过皮肤活检或自主神经功能测试被诊断为SFN，并且通过ELISA对ANCA呈血清阳性。
结果：概述了六个患者，包括4名女性和2名男性。4例抗原特异性抗体为单纯MPO，1例单独使用PR3，1例同时使用MPO和PR3。2例患者出现系统性血管炎。5例患者接受了免疫抑制。三名患者经历了部分改善，3例患者症状稳定。
结论：这是第一系列疑似免疫介导的SFN和ANCA抗体阳性的患者，提高ANCA介导的孤立SFN的可能性。这与更典型的ANCA介导的多发性单神经病或轴索感觉运动神经病的周围神经病表现相反。在这些情况下，我们无法明确证明ANCA相关血管炎[AAV]的因果关系；然而，SFN症状的稳定和ANCA抗体滴度的相关改善，AAV治疗后，可能是一种联系。
方法：这是6例SFN和ANCA阳性患者的回顾性病例系列，有和没有系统性表现。包括的患者通过皮肤活检或自主神经功能测试被诊断为SFN，并且通过ELISA对ANCA呈血清阳性。
结果：概述了六个患者，包括4名女性和2名男性。4例抗原特异性抗体为单纯MPO，1例单独使用PR3，1例同时使用MPO和PR3。2例患者出现系统性血管炎。5例患者接受了免疫抑制。三名患者经历了部分改善，3例患者症状稳定。
结论：这是第一系列疑似免疫介导的SFN和ANCA抗体阳性的患者，提高ANCA介导的孤立SFN的可能性。这与更典型的ANCA介导的多发性单神经病或轴索感觉运动神经病的周围神经病表现相反。在这些情况下，我们无法明确证明ANCA相关血管炎[AAV]的因果关系；然而，SFN症状的稳定和ANCA抗体滴度的相关改善，AAV治疗后，可能是一种联系。
