PRIME Journal Vol. 11 Issue 4

respiratory, auto-immune and neurologic disorders. Furthermore, chronic inflammation is a feature of both rosacea and several systemic co-morbidities, notably cardiometabolic disease 5,6 . In addition, genome-wide association studies (studying the human genome and comparing it to otherswith a similar disease or condition) identified (chromosomal) loci for rosacea that were also associated with several auto-immune diseases, such as diabetes mellitus, coeliac disease, and rheumatoid arthritis 7 . Rosacea and gut health Association studies linking rosacea to the gastrointestinal system have shown a link with inflammatory bowel disease and overgrowth of gut bacteria (both H.pylori and small intestinal bowel overgrowth) 8 . The microenvironment in the gut is increasingly linked to skin inflammation with gut dysbiosis (an alteration in the harmonious composition of the gut microbiome) playing an important role in immunity as well as controlling inflammatory signalling that maymanifest in facial skin. This can either be through the mediation of inflammation through cytokines and other inflammatory mediators or through mucosal barrier compromise, often known as the leaky gut 9 . Gut dysbiosis is an imbalance that is affected by multiple factors, including age, food consumption, stress and antibiotics (in anti-microbial doses). Intestinal inflammation and gut dysbiosis activate the plasma kallikrein-kinin system pathway, which is pro-inflammatory in rosacea and identified as a key step in its inflammatory cascade 10 . In addition, gut dysbiosis leads to mucosal barrier compromise, which, as a consequence, leads to the increase in pro-inflammatory substances circulating in the bloodstream. Control of the harmonious gut microbial environment, as well as the inflammation, can in turn have a positive effect on the control of rosacea symptoms and is increasingly being recognised as part of the overall management of rosacea through a number of interventions such as dietarymodification, consumption of probiotics, as well as control and eradication of potentially pathogenic microbes such as H.pylori and small intestinal bowel overgrowth 11 . Gastrin-induced flushing, a symptom commonly found in rosacea patients, has also been linked to the presence of H.pylori 8 . In clinical practice, this can be an additional approach in the management of rosacea patients, namely those who do express gastrointestinal symptoms andmay therefore have gut inflammation or bacterial overgrowth could benefit from bacterial eradication and control of inflammation. It is, therefore, of importance that rosacea patients are asked and probed for any gastrointestinal symptoms that might be associated with or contribute to their rosacea symptoms. The skin microbiome The skin microbiome too has increasingly been recognised to play a role in several inflammatory cutaneous diseases, including rosacea 12 . The skin microbiome refers to the diverse microbial population unique to each individual comprising of bacteria, viruses, fungi, and mites. Some are skin residents and act as symbionts, while others are invaders and often pathogenic. Advances in genomic sequencing research, as opposed to outdated culture- based techniques, have paved the way for a much better understanding of the microbiome’s composition on human skin.Theskinmicrobiome is a delicate environment affected by a number of factors, such as the skin’s acidity, temperature, lipid composition, humidity, stress, pollution, dehydration, and local skin The skinmicrobiome is a delicate environment affected by a number of factors, such as the skin’s acidity, temperature, lipid composition, humidity, stress, pollution, dehydration, and local skin changes such as dry or moist skin. Figure 3 (A) before and (B) after of a patient significantly improved after dietary modification and gut treatment 40 September/October 2021 | AESTHETIC FEATURE | ROSACEA |