Patients with rheumatoid arthritis (RA) are at increased risk of manifestations such as serious infectious events (SIEs), malignancies and cardiovascular disease (1). Moreover, a long administration of drugs is required in this chronic disease, a condition that is responsible of a greater risk of side effects. As an example, there is an almost 2-fold greater risk on a SIE in patients with RA than in general population (2). Furthermore bacterial infection, one of the leading cause of morbidity and mortality in RA patients (3), is not an uncommon side effect of therapy. In addition, the use of corticosteroids, even at low doses (10 mg per day or less), utilized in approximately 65% of patients in randomized clinical trials is an important contributory factor to the increased prevalence of SIEs among RA patients (2, 4)...