F-18 FDG-positron emission tomographic scanning and Wegener's granulomatosis.

Wegener's granulomatosis is a necrotizing granulomatous vasculitis that mainly affects the upper airways, lungs, and kidneys. Autoimmune mechanisms are hypothesized to play a role in the pathophysiology of the disease. F-18 fluorodeoxyglucose-positron emission tomographic scanning is normally used to differentiate benign from malignant disease as a result of differences in glucose metabolism. The authors present a case of Wegener's granulomatosis in which F-18 fluorodeoxyglucose-positron emission tomographic scanning yielded a false-positive result.