Essential tremor (ET) is the most common movement disorder and share overlapping symptoms with Parkinson’s disease (PD), making differential diagnosis challenging. Gut dysbiosis is regarded crucial in the pathogenesis of PD. Since ET patients also has comorbidity in gastrointestinal disorders, the relationship between gut microbiota and ET really worth investigating and may help distinguishing ET from PD. Fecal samples from 54 ET, 67 de novo PD and 54 normal controls (NC) were collected for 16S ribosomal RNA gene sequencing and quantitative real-time PCR. ET showed lower species richness (Chao1 index) than NC and PD. ET was with Bacteroides-dominant enterotype, while PD was with Ruminococcus-dominant enterotype. Compared with NC, 7 genera were significantly reduced in ET, 4 of which (Ruminococcus, Romboutsia, Mucispirillum, and Aeromonas) were identified to be distinctive with an area under the curve (AUC) of 0.705. Compared to PD, 26 genera were found significantly different from ET, 4 of which (Bacteroides, Fusobacterium, Phascolarctobacterium, and Lachnospira) were found distinguishable with an AUC of 0.756. Clinical association results indicated that Proteus was associated with disease severity (TETRAS) of ET, while Klebsiella was linked to depression and anxiety in ET. Functional predictions revealed that 4 Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways were altered in ET. This study reveals gut dysbiosis in ET and it provides new insight into the pathogenesis of ET and helps distinguishing ET from PD.

特发性震颤 (ET) 是最常见的运动障碍，与帕金森病 (PD) 有重叠的症状，使得鉴别诊断具有挑战性。肠道菌群失调被认为在 PD 的发病机制中至关重要。由于 ET 患者也有胃肠道疾病的合并症，因此肠道微生物群与 ET 之间的关系确实值得研究，并可能有助于区分 ET 和 PD。收集了来自 54 名 ET、67 名新发 PD 和 54 名正常对照 (NC) 的粪便样本，用于 16S 核糖体 RNA 基因测序和定量实时 PCR。ET 的物种丰富度（Chao1 指数）低于 NC 和 PD。ET 是拟杆菌属主导的肠型，而 PD 是瘤胃球菌属主导的肠型。与NC相比，ET显着减少了7个属，其中（Ruminococcus、Romboutsia、Mucispirillum和Aeromonas ) 被鉴定为具有独特性，曲线下面积 (AUC) 为 0.705。与 PD 相比，发现 26 个属与 ET 显着不同，其中 4 个属（拟杆菌属、梭杆菌属、芽孢杆菌属和毛螺菌属）被发现可区分，AUC 为 0.756。临床关联结果表明，变形杆菌与 ET 的疾病严重程度（TETRAS）相关，而克雷伯氏菌与与 ET 中的抑郁和焦虑有关。功能预测显示，4 京都基因和基因组百科全书 (KEGG) 通路在 ET 中发生了改变。这项研究揭示了 ET 中的肠道菌群失调，它为 ET 的发病机制提供了新的见解，并有助于区分 ET 和 PD。