Identification of gut microbiota signatures in symptomatic dermographism.

Symptomatic dermographism (SD) is a recurrent inflammatory skin disease related to immunity; however, the details remain elusive. In view of the important role of gut microbiota in immune regulation, the purpose of this study is to investigate the alterations of gut microbiota in SD and explore the potential bacterial biomarkers for diagnosis. A case-control study including SD patients and normal controls (NCs) was carried out. Gut microbiota of the participants was analysed by the 16S rDNA sequencing of faecal samples. The linear discriminant analysis effect size and the receiver operating characteristic curve (ROC) analysis were used to identify the bacterial biomarkers. Forty-four participants were included in this study. The alpha-diversity and beta-diversity of gut microbiota differed significantly between SD patients and NCs. The abundance of Verrucomicrobia, Ruminococcaceae and their subordinate taxa were reduced in SD patients, while Enterobacteriales and its subordinate taxon exhibited higher relative abundance compared with NCs. Subdoligranulum and Ruminococcus bromii showed a potential diagnostic value for SD, and Prevotella stercorea was negatively relevant to duration of SD. Furthermore, the pyruvate, butyric acid and histamine metabolism pathway were likely to be involved in the pathogenesis of SD. Our results revealed that the gut microbiota of SD patients experienced obvious changes, and Verrucomicrobia, Ruminococcaceae and Enterobacteriales were microbiota signatures for SD.