To date, there is no valuable tool to assess fibrotic disease activity in humans in vivo in a non-invasive way. This study aims to uncouple inflammatory from fibrotic disease activity in fibroinflammatory diseases such as IgG
In this cross-sectional clinical study, 27 patients with inflammatory, fibrotic and overlapping manifestations of IgG
Using combination of 
FAP-specific PET/CT permits the discrimination between inflammatory and fibrotic activity in IgG