Giant cell arteritis (GCA), also called temporal arteritis, is a large- and medium-sized blood vessel systemic vasculitis characterized by the granulomatous involvement of the aorta and its major branches. This vasculitis mainly occurs in white individuals older than 50 years. Due to the progressive aging of the population in Western countries, GCA has emerged as relatively common disease in the elderly. Clinical manifestations of GCA are the result of inflammation of the arterial wall, leading to a series of structural changes, such as intimal hyperplasia and fragmentation of internal elastic laminae and luminal occlusion. Headache is the most typical and common clinical expression of this vasculitis. Visual ischemic manifestations, in particular permanent visual loss, constitute the most feared complications of GCA.
Management of GCA is still fraught with challenges. Corticosteroids are the cornerstone of the therapy in GCA. The use of corticosteroids has dramatically reduced the frequency of blindness in patients with GCA. The initial dose of prednisone or its equivalent ranges between 40-60 mg/day, either as single or divided dose for 3-4 weeks. GCA patients without severe ischemic complications experience rapid disease improvement with an initial prednisone dose of 40 mg/day. In GCA patients who present with severe visual ischemic complication, higher steroid doses, generally an initial dose of 60 mg/prednisone/day or methylprednisolone pulse therapy (1g daily for 3 consecutive days) are given. There are data showing that not the absolute dose but the time from the onset of symptoms to the first administration of corticosteroids is predictive of improvement of visual loss. Regrettably, in most cases once established the prognosis for significant visual recovery in GCA patients despite corticosteroid therapy is poor. Immunosuppressive agents may be considered for use in large vessel vasculitis as adjunctive therapy. In this regard, alternative-corticosteroid sparing drugs, in particular methotrexate (MTX), should be considered in GCA patients with severe corticosteroid-related side effects and/or in those patients who require prolonged corticosteroid therapy due to relapses of the disease. However, a meta-analysis of randomized placebo-controlled trials in patients with newly diagnosed GCA disclosed modest efficacy of MTX (10-15 mg/week) in reducing relapse rate and lowering the cumulative corticosteroid therapy. No clear benefit of anti-TNF-alpha therapy in patients with GCA has been reported. Nevertheless, recent reports indicate that anti-IL6 receptor monoclonal antibody therapy may an effective and relatively safe therapy in patients with inflammatory aortitis refractory to corticosteroids or to other biologic immunosuppressive drugs.
Disclosure of Interest None declared