Diagnosing giant cell temporal arteritis.

Arteritis is a complex and totally underestimated clinical entity that may present in several ways. Due to the diversity of clinical features and the frequent overlapping of clinical syndromes, many different classifications are available for arteritides, but the simplest classification for the practicing physician is the broad division of arteritis into giant cell arteritis and non-giant cell arteritis. Giant cell arteritis encompasses two distinct clinical entities that are pathologically indistinguishable from each other; but both involve arteritis of median and large-sized arteries characterized by an infiltration of giant cells. These include temporal arteritis and Takayasu's arteritis. The non-giant cell arteritis encompasses a greater variety of uncommon diseases that are often associated with other systemic processes such as systemic lupus erythematosus or periarteritis nodosa, and it generally results in ischemic organ dysfunction that is amenable only to medical treatment. Less commonly, however, non-giant cell arteritis may become manifested as acute arterial occlusion caused by circulating anticoagulants, abdominal apoplexy as intra-abdominal bleeding from rupture of micro aneurysms of artery branches, gastrointestinal bleeding from local necrosis of the gastrointestinal tract, or deep-vein thrombosis secondary to hypercoagulable states. Although temporal arteritis has generated a voluminous body of literature, its precise etiology remains elusive. This study summarizes our experience in 15 cases of temporal arteritis and one case is presented to increase knowledge about this disease entity.