Sustained spontaneous clinical remission in giant cell arteritis: Report of two cases with long‐term followup

Abstract

Introduction Corticosteroid treatment usually induces rapid and dramatic relief of giant cell arteritis (GCA)–related clinical manifestations. In addition, corticosteroids reduce the risk of ischemic complications attributed to GCA. This observation is supported by the marked reduction in frequency of ischemic events since corticosteroid therapy was first used to treat GCA in the 1950s (1) by the fact that patients rarely experience ischemic complications after starting treatment, and by the observation that corticosteroids may abrogate recurrent episodes of amaurosis fugax and may sometimes reverse visual loss if administered promptly (2). Therefore, high-dose corticosteroids remain the initial treatment of choice for patients with GCA. Corticosteroids rapidly induce functional changes in temporal artery lesions. Expression of interleukin-2 (IL-2), IL-2 receptor, endothelial cell adhesion molecules (e.g., E-selectin and vascular cell adhesion molecule 1), and proinflammatory cytokines (e.g., IL-1 and IL-6) has been shown to be significantly lower in temporal artery lesions from patients with GCA or in GCA-affected human temporal arteries engrafted into severe combined immunodeficient mice upon corticosteroid treatment (3–5). It is likely that these and other functional changes contribute to remission of clinical symptoms. Although functional changes occur rapidly after corticosteroid administration, persistence of inflammatory infiltrates can be found in totally asymptomatic individuals receiving corticosteroid treatment, and in fact recurrences are frequent when corticosteroids are tapered or withdrawn (6). Over months or years, lesions usually evolve to a healing or obsolescent stage defined histologically by the presence of fibrotic changes in the media, irregular intimal thickening, and persistence of scattered foci of inflammatory cells (7). Corticosteroid requirements are highly variable among patients (6,8). Some patients easily enter sustained remission with relatively short duration of treatment, whereas others experience relapsing chronic disease that requires remarkable cumulative corticosteroid therapy to maintain remission (6,8). Early reports prior to the corticosteroid era depicted instances of spontaneous remission, although no longterm systematic followup of these patients was described (9,10). In addition, a survey of 100 unselected necropsies revealed “healing” GCA lesions in the temporal arteries of 2 elderly patients who died from unrelated conditions and had never been recognized to have symptoms of GCA, suggesting that in these patients, GCA had been asymptomatic, or not symptomatic enough to require medical attention (11). These observations suggest that, in some cases, the GCA inflammatory process may spontaneously evolve into an obsolescent, clinically silent stage. We illustrate this point by describing 2 patients with biopsyproven GCA who underwent spontaneous, long-lasting clinical remission with no treatment.