Rosacea and the Microbiome: A Systematic Review.

Rosacea, a chronic inflammatory skin disease characterized by recurrent episodes of facial flushing, erythema, pustules, and telangiectasia, largely affects fair-skinned women over 30 years of age. Although a long-recognized entity, the exact pathophysiology of this disease is still debated. Current theories highlight the role of the cutaneous microbiome and its associated inflammatory effects in rosacea's pathogenesis. However, microbiological reverberations are not limited to the skin, as recent studies have described the potential cutaneous effects of alterations in the gastrointestinal (GI) microbiome. Associations with additional GI pathologies, including small intestinal bacterial overgrowth (SIBO), irritable bowel syndrome (IBS), and inflammatory bowel disease (IBD), have been investigated, as well as Helicobacter pylori infection. In an attempt to better understand and characterize these relationships, as well as current treatment options, we conducted a systematic review of the literature in PubMed, Cochrane, and Embase from their inception to August 6, 2020. We have synthesized the literature findings within three sections of this manuscript: the cutaneous microbiome, the gut microbiome, and therapeutic strategies. Future studies should focus on specific mechanisms linking GI pathology with rosacea manifestations and the role of enteral drugs in mitigating cutaneous symptoms.