TY - JOUR
T1 - Biodistribution of the radionuclides 18F-FDG, 11C-methionine, 11C-PK11195, and 68Ga-citrate in domestic juvenile female pigs and morphological and molecular imaging of the tracers in hematogenously disseminated Staphylococcus aureus lesions
AU - Afzelius, Pia
AU - Nielsen, Ole Lerberg
AU - Alstrup, Aage K. O.
AU - Bender, Dirk
AU - Leifsson, Páll S.
AU - Jensen, Svend B.
AU - Schønheyder, Henrik C.
PY - 2016
Y1 - 2016
N2 - Approximately 5-7% of acute-care patients suffer from bacteremia. Bacteremia may give rise to bacterial spread to different tissues. Conventional imaging procedures as X-ray, Computed Tomography (CT), Magnetic Resonance Imaging (MRI), and ultrasound are often first-line imaging methods for identification and localization of infection. These methods are, however, not always successful. Early identification and localization of infection is critical for the appropriate and timely selection of therapy. The aim of this study was thus; a head to head comparison of 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography (PET) to PET with tracers that potentially could improve uncovering of infectious lesions in soft tissues. We chose 11C-methionine, 11C-PK11195, and 68Ga-citrate as tracers and besides presenting their bio-distribution we validated their diagnostic utility in pigs with experimental bacterial infection. Four juvenile 14-15 weeks old female domestic pigs were scanned seven days after intra-arterial inoculation in the right femoral artery with a porcine strain of S. aureus using a sequential scanning protocol with 18F-FDG, 11C-methionine, 11C-PK11195 and 68Ga-citrate. This was followed by necropsy of the pigs consisting of gross pathology, histopathology and microbial examination. The pigs primarily developed lesions in lungs and neck muscles. 18F-FDG had higher infection to background ratios and accumulated in most infectious foci caused by S. aureus, while 11C-methionine and particularly 11C-PK11195 and 68Ga-citrate accumulated to a lesser extent in infectious foci. 18F-FDG-uptake was seen in the areas of inflammatory cells and to a much lesser extent in reparative infiltration surrounding necrotic regions.
AB - Approximately 5-7% of acute-care patients suffer from bacteremia. Bacteremia may give rise to bacterial spread to different tissues. Conventional imaging procedures as X-ray, Computed Tomography (CT), Magnetic Resonance Imaging (MRI), and ultrasound are often first-line imaging methods for identification and localization of infection. These methods are, however, not always successful. Early identification and localization of infection is critical for the appropriate and timely selection of therapy. The aim of this study was thus; a head to head comparison of 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography (PET) to PET with tracers that potentially could improve uncovering of infectious lesions in soft tissues. We chose 11C-methionine, 11C-PK11195, and 68Ga-citrate as tracers and besides presenting their bio-distribution we validated their diagnostic utility in pigs with experimental bacterial infection. Four juvenile 14-15 weeks old female domestic pigs were scanned seven days after intra-arterial inoculation in the right femoral artery with a porcine strain of S. aureus using a sequential scanning protocol with 18F-FDG, 11C-methionine, 11C-PK11195 and 68Ga-citrate. This was followed by necropsy of the pigs consisting of gross pathology, histopathology and microbial examination. The pigs primarily developed lesions in lungs and neck muscles. 18F-FDG had higher infection to background ratios and accumulated in most infectious foci caused by S. aureus, while 11C-methionine and particularly 11C-PK11195 and 68Ga-citrate accumulated to a lesser extent in infectious foci. 18F-FDG-uptake was seen in the areas of inflammatory cells and to a much lesser extent in reparative infiltration surrounding necrotic regions.
M3 - Journal article
VL - 6
SP - 42
EP - 58
JO - American Journal of Nuclear Medicine and Molecular Imaging
JF - American Journal of Nuclear Medicine and Molecular Imaging
SN - 2160-8407
IS - 1
ER -