Rheumatic diseases are chronic conditions which affect a large proportion of the population worldwide (1). Among them, inflammatory chronic diseases including rheumatoid arthritis (RA), spondyloarthritis (SpA), crystal-induced arthritis (CIA), and connective tissue autoimmune diseases, such as systemic lupus erythematosus (SLE) and systemic sclerosis (SSc), are the most common. Chronic inflammation has been recognized to play a role also in osteoarthritis (OA), classically considered a non-inflammatory form of arthritis. Although different risk factors influence their onset and development, these heterogeneous conditions share common clinical outcome including joint pain, disability, and comorbidities (2). Over the last years increasing attention have been paid to the role of diet in the pathogenesis and progression of rheumatic diseases. It has been observed that healthy dietary habits and the consumption of foods rich in bioactive compounds, omega-3 fatty acids, and antioxidants are associated with a lower risk to develop these diseases and a less severe clinical outcome (3). In particular, an important link between gut microbiota and patients' clinical features highlighted the possibility to modulate disease progression and presentation through microbiota manipulation. In this setting, an emerging role might be attributed to probiotics, live microorganisms that, when administered in adequate amounts, confer a health benefit on the host (4). The most commonly used are Lactobacilli (L.), Bifidobacteria (B.), and Streptococci (S.), either as single species or in mixed culture. Their health effects are largely recognized and supported by randomized controlled clinical trials (RCTs) and meta-analyses conducted on infectious diseases, antibiotic-associated diarrhea, irritable bowel syndrome, abdominal pain, and colitis (5, 6).