The assessment of biologic treatment in patients with rheumatoid arthritis using FDG-PET/CT

Rheumatology, 04/18/2012

Okamura K et al. – The FDG uptake observed in the inflamed RA joints may reflect disease activity. The FDG–PET response was correlated with the clinical response to the biologic treatment of RA.


  • Twenty–two patients who received anti–TNF therapies, including infliximab for 16 patients and etanercept for 6 patients, were assessed.
  • PET with 18F–FDG studies and clinical assessments were performed at baseline and 6 months after the initiation of therapy.
  • The maximal standardized uptake value (SUVmax) was used as a representative value for the assessment of the FDG uptake in the bilateral shoulder, elbow, wrist, hip, knee and ankle joints.
  • Spearman’s rank correlation test was applied to assess the correlation between the SUV and the clinical parameters.


  • The ΔSUV (12 joints), the difference in the SUVmax of the affected 12 joints before and after treatment, was positively correlated with the ΔDAS28 (r = 0.609, P = 0.003), ΔDAS28–CRP (r = 0.656, P = 0.001) and Δtender joint count (TJC) (r = 0.609, P = 0.003).
  • There were also significantly positive correlations between ΔSUV (8 joints); the difference in the SUVmax of the bilateral shoulder, elbow, wrist and knee joints before and after treatment and the ΔDAS28 (r = 0.642, P = 0.001), ΔDAS28–CRP (r = 0.712, P < 0.001) and ΔTJC (r = 0.608, P = 0.003), respectively.

Print Article Summary Cat 2 CME Report