Diagnosis

Rheumatoid arthritis (RA) affects approximately 1% of the adult population. It is currently considered a chronic disease for which there is no cure, but remission has become an achievable goal with optimal treatment. Both disability and enormous cost are functions of the disease over time. It is therefore crucial to treat RA early and persistently until remission is present. The challenge of treatment of early RA is not the lack of effective medicine, but rather the ethical and economic considerations related to risk-benefit and cost-benefit. Overtreating patients with disease-modifying antirheumatic drugs (DMARDs) is often feared, but the potential undertreatment of patients with RA can have accelerated structural consequences. This chapter covers diagnosis of RA, from the initial evaluation of patients with new-onset arthritis to important differential diagnoses. Critical diagnostic features are explained, and the 2010 European League Against Rheumatism (EULAR) classification criteria are described and rationalized. The importance of distinction between classification and diagnosis is highlighted.