Advances and challenges in the diagnosis and treatment of polymyalgia rheumatica

Polymyalgia rheumatica (PMR) is a common inflammatory condition that often affects people over the age of 50 years. Characteristic symptoms are shoulder and hip girdle pain and prolonged morning stiffness. Markers of inflammation are often elevated. Clinicians are often faced with the challenge of distinguishing PMR from other conditions, particularly rheumatoid arthritis and spondyloarthropathy that can mimic symptoms of PMR in older people. Additionally, there is an association between PMR and giant cell arteritis, a common large-vessel vasculitis which also affects people over the age of 50 years. Imaging of the large vessels in asymptomatic patients with PMR often reveals findings of subclinical vasculitis. Presently, there are no tests that are specific for the diagnosis of PMR and clinicians rely on a combination of history, physical examination, laboratory tests and imaging studies to make a diagnosis. A recent undertaking by the European League Against Rheumatism/American College of Rheumatology has led to the publication of provisional classification criteria of PMR. Ultrasonography, which is being increasingly used by rheumatologists, can greatly aid in the diagnosis of PMR and often shows changes of synovitis and tenosynovitis. Treatment consists of low doses of glucocorticoids which are associated with morbidity. Evaluation of newer biologic therapies targeting inflammatory cytokines is underway. Despite treatment, relapses are common.