Microbial Dysbiosis in Rheumatoid Arthritis

Inclusion Criteria: * 18-65 years of age * RA diagnosis based on ACR 2010 classification criteria with symptoms starting within the last 2 years * Referred by GP to the Early Arthritis Clinic at the Norfolk and Norwich University Hospitals NHS trust * Commencing methotrexate monotherapy for the first time Exclusion Criteria: * Initially commencing combination therapy (prior to first stool sample) rather than methotrexate monotherapy i.e. MTX combined with another DMARD or prednisolone * Commencement of MTX therapy prior to first stool sample or cessation of MTX therapy at any point during the study * History of psoriasis * Those currently suffering from, or have ever suffered from, any diagnosed gastrointestinal disease, gastrointestinal disorders including regular diarrhoea and constipation (excluding hiatus hernia unless symptomatic) and/or have undergone gastrointestinal surgery. * Those regularly (3+ times/week) taking self-prescribed over the counter medications for digestive/gastrointestinal conditions * Use of laxatives within 7 days prior to sampling unless these have been used on a regular basis (3+ times/week) for more than one month prior to the study and will continue to be used throughout the study period * The use of over-the-counter medications or food/drinks containing pre and/or probiotics within 7 days prior to sampling, unless these have been used on a regular basis (3+ times/week) for more than one month prior to the study and will continue to be used throughout the study period * Significant alteration of the participant's normal diet at any point during the study (e.g. adoption of the 5:2 fasting diet) * Regular (3+ times/week) or recent (within 3 months) use of colonic irrigation or other bowel cleansing techniques * Recently returned to the UK following a period abroad, and who have suffered gastric symptoms during the period abroad or on return to the UK. These will be assessed on an individual basis * Currently taking or finished a course of antibiotics within the last 3 months * Currently pregnant or lactating * Living with or related to any member of the Study Team * Those who have limited or no understanding of spoken and written English