Species-Level Comparative Metagenomic Analysis of the Bacterial Abundance of the Gut Microbiome in Psoriasis, Hidradenitis Suppurativa, and Pemphigus Foliaceous Patients Using Shotgun Next-Generation Sequencing

Recent studies have revealed a specific relationship between gut bacteria and inflammatory skin profiles. We aimed to perform a species-level comparative metagenomic analysis of the gut microbiome in patients with psoriasis, hidradenitis suppurativa (HS), and pemphigus foliaceus (PF). We included omnivorous nonsmokers and nondrinkers with psoriasis (<i>n</i> = 24), HS (<i>n</i> = 10), and PF (<i>n</i> = 11), as well as healthy controls (<i>n</i> = 10). We collected faecal samples from all patients for classic parasitological analysis. Gut microbiome analysis was conducted using shotgun next-generation sequencing. We used the Deseq2, Limma_voom, LinDA, and MaAMaAsLin 2 bioinformatics tools to evaluate concordance and differential abundance between patients. Thirteen patients (23.64%) were diagnosed with active intestinal parasitosis. The presence of intestinal parasitosis was significantly related to immunosuppression (<i>p</i> = 0.009). The most abundant microorganism species found in the faeces of the patients evaluated was <i>Escherichia coli</i>. Psoriasis patients presented a greater abundance of bacteria from the Veillonellaceae family, whereas PF patients presented a greater abundance of Firmicutes bacteria. Patients with PF showed increased <i>E. coli</i> virulence and antibiotic resistance functional markers. Immunosuppression significantly influenced the presence of intestinal parasitosis as well as increased the virulence of functional markers in patients with PF receiving systemic corticosteroid therapy.