A retrospective cohort study to assess PET-CT findings and clinical outcomes in Takayasu arteritis: does 18F-fluorodeoxyglucose uptake in arteries predict relapses?

The objective of this study is to investigate the use of PET-CT scan with 18F-fluorodeoxyglucose (18F-FDG) as a method to predict outcomes in patients with Takayasu arteritis (TAK), as well as to analyze associations between 18F-FDG PET-CT findings with disease relapses, sustained remission, new angiographic lesions, ischemic events, and changes in therapy for TAK. At baseline assessment, 36 TAK patients underwent 18F-FDG PET-CT scan and maximal standardized uptake value (SUVmax) in arteries ≥ 1.3 was predictive for clinical disease activity. Thirty-two TAK patients were then followed-up for a median 83.5 months. Twenty-three (71.9%) patients developed clinical relapses and new arterial lesions were observed in 14 (43.8%) cases. Disease relapses [85.0% vs. 50.0%, p = 0.049; odds ratio (OR): 5.667; 95% confidence interval (95 CI): 1.067-30.085] and the need for changing immunosuppressive therapy (85.0% vs. 41.7%, p = 0.018; OR: 7.933; 95CI: 1.478-42.581) were more frequently found in patients with SUVmax ≥ 1.3 at baseline compared with those presenting SUVmax < 1.3. No associations were found between SUVmax ≥ or < 1.3 in large arteries at baseline and the development of ischemic events, sustained remission or new angiographic lesions. In multivariate analysis, associations between baseline SUVmax ≥ 1.3 and disease relapses were not independent (hazard ratio: 1.07; 95 CI 0.39-2.92; p = 0.892). In conclusion, arterial SUVmax is marginally associated with disease relapses and with the need to change therapy in TAK. 18F-FDG uptake in large arteries is not associated with the development of new arterial lesions in TAK.

Takayasu arteritis: assessment of response to medical therapy based on clinical activity criteria and imaging techniques.

In this retrospective longitudinal cohort study we included 52 patients with Takayasu arteritis (TA) who were on regular follow-up at the Vasculitis Unit of Universidade Federal de São Paulo between 2003 and 2009. The mean age at study was 38 years and the mean age at diagnosis was 29 years. Patients were followed for a mean 74.3 months. A relapse-remitting course was observed in 41 patients (78.8%) whereas 9 (17.3%) had a monophasic course and only 2 (3.8%) patients were chronic-active. Disease remission was achieved in 50 patients (96.2%). Angiographic type V was observed in 42.3% of TA patients at diagnosis and in 61.5% during follow-up. The most affected arteries were the abdominal aorta (63.5%) and left subclavian (60.6%). Prednisone was used by 94% of TA patients and immunosuppressive agents were prescribed for 51 (98%) patients. Methotrexate was used by 82.7%, followed by cyclophosphamide (26.9%), azathioprine (25.0%), anti-TNFα agents (5.8%) and leflunomide (5.8%). Although, forty patients (76.9%) used prednisone and methotrexate as initial treatment, 75% of them developed new vascular lesions along follow-up. Eighteen TA patients (34.6%) needed to change immunosuppressive therapy due to failure or toxicity, among them 83.3% presented new lesions. Surgical treatment was performed in 34.6% of patients and restenosis was observed in 13.5% in a median time of 11 months after surgery. In conclusion besides prednisone and methotrexate is largely used in TA, the majority of patients still develop new arterial lesions along time.