LAUSR

Giant cell arteritis (GCA) was originally described as granulomatous vasculopathy in carotid artery branches, particularly in superficial temporal arteries. Thus, the classical 1990 American College of Rheumatology (ACR) criteria for classification of GCA are markedly orientated towards cranial symptoms and findings (1). However, recent studies have shown that the aorta and its main branches are frequently involved in patients with GCA as well as in those with Takayasu arteritis (2–4). In addition, it has been shown that computed tomographic angiography (CTA) can reveal vascular abnormalities highly suggestive of aortic inflammation (5, 6). Fluorodeoxyglucose–positron emission tomography has also been reported to be useful for detecting aortic inflammation (7, 8). Temporal artery biopsy has been the gold standard to diagnose GCA based on ACR criteria, in spite of the improvements in these imaging techniques. In this study, we retrospectively assessed the clinical, imaging, and pathological findings of patients with GCA to reconsider whether temporal arteries should be biopsied to diagnose GCA. The studywas performed in accordancewith theDeclaration of Helsinki and the principles of good clinical practice. Approval was obtained from the local ethics committee. The study included consecutive patients with GCA diagnosed according to ACR criteria and/or radiographic evidence of aortitis at Tomakomai City Hospital between 2008 and 2018. Clinical symptoms, laboratory findings, CTA images, and pathology of temporal arteries were collected from the available medical records. Inflammatory findings on CTA were defined as the presence of circumferential wall thickening and/or vascular stenosis, dilation, or aneurysm, judged by independent radiologists. Positive results of temporal artery biopsy were determined in accordance with ACR criteria. In univariate analysis, continuous variables were compared using Wilcoxon’s test, and categorical variables by the chi-squared test. Variables with a probability value less than 0.1 were assessed multivariately by a logistic regression model. Agreement between two variables was evaluated using Cohen’s kappa coefficient. Statistical significance was defined as a probability value < 0.05. Twenty-six patients with GCA were enrolled in the study. Fever was the most frequent symptom, found in 16 patients, followed by a headache in 12 patients. CTA detected inflammation of the aorta and/or its main branches in 20 patients. Temporal artery biopsy was performed in 21 patients, revealing vasculitis in 11 of them (Table 1). More patients with biopsy-positive GCA were female than those with biopsy-negative GCA (91% vs 40%, p = 0.01). Out of 11 patients with biopsy-positive GCA, only four (36%) had headache and/or jaw claudication. Temporal artery abnormalities by physical examination were also less frequent (27%) in patients with biopsy-positive GCA than in biopsy-positive patients. Abdominal/back pain was found more frequently in patients with biopsy-positive GCA, although this was not statistically significant (45% vs 10%, p = 0.07). The erythrocyte sedimentation rate was higher in patients with biopsy-positive GCA (median 125 mm/h vs 81 mm/h, p = 0.03). CTA displayed inflammatory findings in the thoracic/abdominal aorta (91%) and subclavian artery (64%) more frequently in patients with biopsy-positive GCA. Multivariate analysis revealed that being female, having abdominal/back pain, and having thoracic/abdominal aortitis were independently frequent in patients with biopsy-positive GCA. Agreement was high between biopsy results and gender (κ = 0.51) or inflammation of the thoracic aorta (κ = 0.52)/abdominal aorta (κ = 0.61) on CTA, whereas it was low between biopsy results and any symptoms. Our data confirmed that thoracic/abdominal aortitis was common in patients with GCA, particularly in those with biopsy-positive GCA, consistent with previous reports (2–6). Contrary to our expectation, cranial symptoms were uncommon in our patients with biopsy-positive GCA. This suggests that temporal artery biopsymight be recommended for patients with suspicion of GCA regardless of cranial symptoms. However, positive results on the temporal artery biopsy were strongly correlated with inflammatory findings in the thoracic/abdominal aorta. We consider that CTA could become a promising examination for the diagnosis ofGCAas an alternative to temporal artery biopsy, although this was a single-centre experience limited to a small number of patients.