[Polymyalgia rheumatica and temporal arteritis]

Polymyalgia rheumatica (PMR) and giant cell arteritis (GCA) are closely related and frequently occurring inflammatory diseases with an incidence of 50 and 18 per 100,000 per year, respectively, in people aged 50 years or over. The most frequent symptom of PMR is aching and morning stiffness lasting more than 1 month and exacerbated by movement, occurring in the shoulder and pelvic girdles and in the neck region. GCA is vasculitis of the large and medium-sized arteries that originate from the aortic arch, causing new and marked headache localised over the temporal or occipital areas, jaw claudication, visual impairment or claudication of the arms. GCA is characterised by histopathological panarteritis with a predominantly lymphohistiocytic cell infiltrate. Activation of macrophages is central to the arteritis. Standard treatment for PMR and GCA is glucocorticoids, which may consist of prednisone 10-20 mg/day or its equivalent for PMR patients and prednisone 30-40 mg to 1 mg/kg body weight for GCA patients. For GCA patients with recently impaired vision, treatment should start with high doses of intravenously administered glucocorticoids, such as methylprednisolone 1 g/day for 3 consecutive days. A treatment duration of 1-2 years is often required for patients with PMR or GCA; because of the side effects associated with long-term use of glucocorticoids, osteoporosis prophylaxis with oral calcium supplementation, vitamin D and bisphosphonates is appropriate.