Altered Skin and Gut Microbiome in Hidradenitis Suppurativa

AbstractIntroductionHidradenitis suppurativa (HS) is a chronic inflammatory skin disease characterized by the formation of nodules, abscesses, and fistula at intertriginous sites. The skin-gut axis is an area of emerging research in inflammatory skin disease and may provide answers to the pathogenesis of HS. Methods59 patients with HS provided fecal samples, nasal and skin swabs of affected sites for analysis. 30 healthy controls provided fecal samples and 20 healthy controls provided nasal and skin swabs. We performed 16s rRNA gene amplicon sequencing on total DNA derived from the samples.Results and DiscussionMicrobiome alpha diversity was significantly lower in the fecal, skin and nasal samples of individuals with HS which may be secondary to disease biology or related to antibiotic usage. Ruminococcus gnavus was more abundant in the fecal microbiome of individuals with HS, which is also noted in Crohn's disease (CD), and may suggest comorbidity due to shared gut microbiota alterations. Finegoldia magna was found overrepresented in HS skin samples relative to healthy controls. It is possible local inflammation is driven by F. magna through promoting the formation of neutrophil extracellular traps (NET). These changes in both the gut and skin microbiome warrant further exploration, as therapeutic strategies including faecal microbiota transplant (FMT) and phage therapy may be of benefit.

摘要与引言
化脓性汗腺炎（Hidradenitis suppurativa, HS）是一种慢性炎症性皮肤病，以间擦部位形成结节、脓肿及瘘管为主要特征。皮肤-肠道轴（skin-gut axis）是炎症性皮肤病领域的新兴研究方向，或可为HS的发病机制提供关键解答。

方法
本研究纳入59例HS患者，收集其粪便样本以及受累部位的鼻拭子、皮肤拭子用于检测分析；另招募30名健康对照者提供粪便样本，20名健康对照者提供鼻拭子与皮肤拭子。对所有样本提取的总DNA进行16S rRNA基因扩增子测序（16s rRNA gene amplicon sequencing）。

结果与讨论
HS患者的粪便、皮肤及鼻拭子样本的微生物组α多样性均显著降低，该现象可能继发于疾病本身的病理生理过程，亦或与抗生素使用相关。HS患者粪便微生物组中格氏瘤胃球菌（Ruminococcus gnavus）丰度更高，这一特征同样见于克罗恩病（Crohn's disease, CD），提示二者或因共有肠道菌群改变而存在共病风险。与健康对照相比，HS患者皮肤样本中大芬戈尔德菌（Finegoldia magna）丰度升高，推测该菌可通过促进中性粒细胞胞外陷阱（neutrophil extracellular traps, NET）的形成介导局部炎症反应。肠道与皮肤微生物组的上述改变值得进一步深入探究，粪便菌群移植（FMT, faecal microbiota transplant）及噬菌体疗法等治疗策略或可使患者获益。