Utility of 11C-methionine and 11C-donepezil for imaging of Staphylococcus aureus induced osteomyelitis in a juvenile porcine model: comparison to autologous 111In-labelled leukocytes 99mTc-DPD and 18F-FDG

摘要

The aim of this study was to compare ¹¹C-methionine and ¹¹C-donepezil positron emission tomography (PET) with ¹¹¹In-labeled leukocyte and ^99mTc-DPD (Tc-99m 3,3-diphosphono-1,2-propanedicarboxylic acid) single-photon emission computed tomography (SPECT), and ¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) PET to improve detection of osteomyelitis. The tracers’ diagnostic utility where tested in a juvenile porcine hematogenously induced osteomyelitis model comparable to osteomyelitis in children. Five 8-9 weeks old female domestic pigs were scanned seven days after intra-arterial inoculation in the right femoral artery with a porcine strain of Staphylococcus aureus. The sequential scan protocol included Computed Tomography, ¹¹C-methionine and ¹¹C-donepezil PET, ^99mTc-DPD and ¹¹¹In-labelled leukocytes scintigraphy, and ¹⁸F-FDG PET. This was followed by necropsy of the pigs and gross pathology, histopathology, and microbial examination. The pigs developed a total of 24 osteomyelitic lesions, 4 lesions characterized as contiguous abscesses and pulmonary abscesses (in two pigs). By comparing the 24 osteomyelitic lesions, ¹⁸F-FDG accumulated in 100%, ¹¹¹In-leukocytes in 79%, ¹¹C-methionine in 79%, ¹¹C-donepezil in 58%, and ^99mTc-DPD in none. Overall, ¹⁸F-FDG PET was superior to ¹¹¹In-leukocyte SPECT and ¹¹C-methionine in marking infectious lesions.