Negative 18F-FDG and Positive 68Ga-FAPI-04 Findings in a Patient With Acute Cholangitis

68 Ga-FAPI PET demonstrates superior detection of primary lesions in cholangiocarcinoma compared with 18 F-FDG PET, making it commonly used in the diagnosis of biliary diseases. Herein, we reported the 18 F-FDG and 68 Ga-FAPI-04 PET/MR findings in a 38-year-old man experiencing acute cholangitis. The lesions exhibited negative 18 F-FDG uptake but intense 68 Ga-FAPI-04 uptake on PET/MR.