Intense FDG uptake on PET/CT in the upper and lower respiratory system indicative of Wegener's granulomatosis

Wegener's granulomatosis (WG) is an uncommon systemic vasculitis, which involves the upper and lower respiratory tracts and the kidneys. Because the patients generally present with clinical manifestations that are similar to common diseases, WG may be initially misdiagnosed as infection or malignancy. We report the case of a 55-year-old male presenting with weight loss, cough, hemoptysis, low-grade fever, and pulmonary nodules detected on the thoracic CT scan. Malignancy was initially suspected, so a PET/CT was performed. It demonstrated intense FDG uptake in the upper and lower respiratory system. The diagnosis of WG was based on PET findings, elevated serum levels of inflammatory markers, and the presence of c-ANCA. We consider that the knowledge of FDG-PET/CT findings may help to make an easier and earlier diagnosis of WG.