Purpose of review: To discuss recent findings on the epidemiology and pathogenesis of extra-articular manifestations in rheumatoid arthritis (RA), and provide an update on the literature on treatment of patients with extra-articular RA (ExRA) manifestations.
Recent findings: ExRA is associated with increased comorbidity and mortality. Several surveys suggest that some ExRA manifestations, in particular vasculitis, occur less frequently than previously reported. This is probably due to improved overall control of disease activity. Active RA with high disease activity is associated with increased risk of severe ExRA manifestations. Studies on the impact of treatment with biologics on the occurrence of ExRA are inconclusive. Circulating immune complexes and T cells have been implicated in the pathogenesis of ExRA. The genetic background and related disease mechanisms may be somewhat different in manifestations such as vasculitis and interstitial lung disease. Limited data support a benefit from treatment with cyclophosphamide, TNF-inhibitors or rituximab in patients with severe ExRA.
Summary: ExRA remains a major diagnostic and therapeutic challenge in some patients. Further studies of the pathogenesis of systemic involvement and on the effect of treatment on such mechanisms may be helpful for further improvement of the management of RA.