Clinical study of giant cell arteritis in our hospital.

To investigate clinical and laboratory features of giant cell arteritis (GCA).,We included 24 patients (6 men, 18 women; mean age 69.8 years) in this study. GCA was diagnosed based on the American College of Rheumatology 1990 classification criteria.,Mean serum C-reactive protein was 9.03 mg/dl. GCA was classified into three types: classic temporal arteritis type (cranial GCA, nine patients); large-vessel type, affecting the aorta and its major branches without temporal arteries (12 patients); generalized type, affecting both temporal arteries and large vessels (three patients). Swelling and tenderness of temporal arteries were recognized in temporal arteritis and generalized arteritis. Ten of these patients also had histopathologic findings of arteritis, including giant cells in biopsy specimens. Examination of HLA-class 1 expression showed that one patient with cranial GCA, three with generalized GCA, and seven with large-vessel GCA were positive for HLA-A24, and four patients with large-vessel GCA were positive for HLA-B39. One patient with cranial GCA, one with generalized GCA, and six with large-vessel GCA were positive for HLA-B52. Nine patients were positive for anti-phospholipid antibodies (seven for anti-cardiolipin antibody immunoglobulin G, seven for anti-cardiolipin β2-glycoprotein-1 antibody, one for lupus anticoagulant).,Our study demonstrated that HLA-class 1 expression in GCA resembles that in Takayasu arteritis, suggesting that these two arteritis types share the same genetic background. In contrast, the difference in the prevalence of anti-phospholipid antibodies in GCA and Takayasu arteritis patients shows a difference in the characteristic aspects of these two arteritis types.