The fine line between Takayasu arteritis and giant cell arteritis.

The objective of this study is to describe a series of patients above the age of 50 years with large vessel arteritis and vascular involvement typical of TAK. A retrospective review of 18 patients (median age 64 years) with emphasis on clinical characteristics, laboratory values, and vascular involvement by CT, MRI, or planar angiography. Five patients fulfilled the ACR criteria for GCA, five for TAK, three both GCA and TAK, while five patients did not fulfill the criteria for either disease. The dominant presenting symptoms were constitutional, while only a few patients had cranial or peripheral symptoms. Sixty-one percent had physical signs of vascular compromise. Temporal artery biopsy showed giant cell arteritis in six out of nine biopsies. Arterial involvement: 78 % had either involvement of the ascending aorta, the aortic arch, descending or/and abdominal aorta, 9 carotid, 12 subclavian, 5 axillary, 3 renal, 7 iliac, and 2 femoral arteries; 7 mesenteric or celiac trunk. All the patients were treated with prednisone and 50 % with steroid-sparing drug. Nine out of 15 patients (60 %) achieved remission after 1 year of follow-up. No substantial differences in the distribution of vascular involvement, type of treatment, or outcome measures were observed between patients fulfilling criteria for GCA or TAK. Vascular involvement typical of TAK in patients above the age of 50 years with large vessel arteritis seems to be more frequent than previously assumed. Our findings support the assumption that TAK and GCA represent a spectrum of the same disease.