Isolated aortitis versus giant cell arteritis: are they really two sides of the same coin?

Objectives: The aim of the study was to compare epidemiological data, clinical findings and results of investigations in patients with isolated aortitis and those with giant cell arteritis (GCA) to establish whether patients with isolated aortitis differ from those with GCA.

Methods: We reviewed the medical notes of all patients consecutively seen in two Rheumatology centres in the last two decades with a suspicion of GCA, searching for cases characterised by abnormal [18F] fluorodeoxyglucose (FDG) PET uptake of the aorta. 'Isolated aortitis' was defined as increased FDG uptake in the aorta not explained by atherosclerosis in the absence of FDG uptake in other large vessels.

Results: Comparing the epidemiological and clinical data of patients with isolated arteritis with those with GCA, we observed many statistical significant differences. First of all, the male/female ratio was reversed, with a predominant male involvement in isolated arteritis. Moreover, the mean age of patients with isolated arteritis was significantly lower than that of GCA patients (62 vs. 78.4 yrs; p<0.0001). None of the patients with isolated aortitis presented at any time of the disease course the typical symptoms of GCA, while in a low percentage of cases constitutional symptoms represented the only clinical features. Beside the aortic arch, the sites more frequent involved were the thoracic and abdominal tracts, in all cases without an uptake of the aortic branches.

Conclusions: It is not known whether our patients with isolated aortitis represent variants of GCA or TA, nor is it known how they will evolve, but we can certainly conclude that these patients have a different epidemiologic and clinical profile, and do not necessarily represent two sides of the same coin.