Gut dysbiosis is associated with aortic aneurysm formation and progression in Takayasu arteritis

Abstract

AbstractBackgroundTakayasu arteritis (TAK) is an autoimmune large vessel vasculitis that affects the aorta and its major branches, eventually leading to the development of aortic aneurysm and vascular stenosis or occlusion. This retrospective and prospective study aimed to investigate whether the gut dysbiosis exists in patients with TAK and to identify specific gut microorganisms related to aortic aneurysm formation/progression in TAK.MethodsWe analysed the faecal microbiome of 76 patients with TAK and 56 healthy controls (HCs) using 16S ribosomal RNA sequencing. We examined the relationship between the composition of the gut microbiota and clinical parameters.ResultsThe patients with TAK showed an altered gut microbiota with a higher abundance of oral-derived bacteria, such asStreptococcusandCampylobacter, regardless of the disease activity, than HCs. This increase was significantly associated with the administration of a proton pump inhibitor used for preventing gastric ulcers in patients treated with aspirin and glucocorticoids. Among patients taking a proton pump inhibitor,Campylobacterwas more frequently detected in those who underwent vascular surgeries and endovascular therapy for aortic dilatation than in those who did not. Among the genus ofCampylobacter,Campylobacter gracilisin the gut microbiome was significantly associated with clinical events related to aortic aneurysm formation/worsening in patients with TAK. In a prospective analysis, patients with a gut microbiome positive forCampylobacterwere significantly more likely to require interventions for aortic dilatation than those who were negative forCampylobacter. Furthermore, patients with TAK who were positive forC. gracilisby polymerase chain reaction showed a tendency to have severe aortic aneurysms.ConclusionsA specific increase in oral-derivedCampylobacterin the gut may be a novel predictor of aortic aneurysm formation/progression in patients with TAK.