FDG-PET/CT Skull Base to Mid-Thigh Tseng et al [9] performed a single-center retrospective observational study of 53 patients admitted with sepsis of unknown origin who underwent initial workup including unrevealing chest radiography followed by FDG-PET/CT within 2 weeks of sepsis diagnosis. Of these, 35/53 (66%) of patients had positive FDG-PET/CT findings and 13/53 (25%) of patients had treatment modified based on imaging results, which included surgery (9/13) and placement of drainage catheters (4/13). Although the majority of infections identified were musculoskeletal (19/53, 38%), the second most common site of infection was in the chest (13/53, 25%). Kluge et al [10] performed a single-center 6 year retrospective study of critically ill patients with severe sepsis or septic shock of unknown origin. Eighteen patients underwent initial workup, including unrevealing chest radiography followed by FDG-PET/CT (without any other prior cross-sectional imaging). Of these, 14/18 (78%) of patients had positive FDG-PET/CT findings, of which 3/18 (17%) of patients were false positives, 11/18 (61%) of patients were true positives, and 6/18 (33%) of patients had treatment modified based on imaging results, which included surgery and initiation/prolongation of antibiotic therapy. There were no false negatives (100% NPV). Brondserud et al [11] performed a single-center retrospective study of 157 patients with 165 separate episodes of bacteremia of unknown origin who had also undergone FDG-PET/CT as part of workup for infection or sepsis. FDG-PET/CT was able to detect the site of infection in 93/165 scans (56.4%). It was the first modality to identify the site of infection in 41.1% of cases, led to changes in antimicrobial therapy in 14.7% of patients, and resulted in a new infection-related diagnosis unrelated to bacteremia in 9.8% of episodes. FDG-PET/CT had a high clinical impact in 47.3% of cases and was independent of duration of preceding antimicrobial treatment as well as number of days of bacteremia.
Sepsis. FDG-PET/CT Skull Base to Mid-Thigh Tseng et al [9] performed a single-center retrospective observational study of 53 patients admitted with sepsis of unknown origin who underwent initial workup including unrevealing chest radiography followed by FDG-PET/CT within 2 weeks of sepsis diagnosis. Of these, 35/53 (66%) of patients had positive FDG-PET/CT findings and 13/53 (25%) of patients had treatment modified based on imaging results, which included surgery (9/13) and placement of drainage catheters (4/13). Although the majority of infections identified were musculoskeletal (19/53, 38%), the second most common site of infection was in the chest (13/53, 25%). Kluge et al [10] performed a single-center 6 year retrospective study of critically ill patients with severe sepsis or septic shock of unknown origin. Eighteen patients underwent initial workup, including unrevealing chest radiography followed by FDG-PET/CT (without any other prior cross-sectional imaging). Of these, 14/18 (78%) of patients had positive FDG-PET/CT findings, of which 3/18 (17%) of patients were false positives, 11/18 (61%) of patients were true positives, and 6/18 (33%) of patients had treatment modified based on imaging results, which included surgery and initiation/prolongation of antibiotic therapy. There were no false negatives (100% NPV). Brondserud et al [11] performed a single-center retrospective study of 157 patients with 165 separate episodes of bacteremia of unknown origin who had also undergone FDG-PET/CT as part of workup for infection or sepsis. FDG-PET/CT was able to detect the site of infection in 93/165 scans (56.4%). It was the first modality to identify the site of infection in 41.1% of cases, led to changes in antimicrobial therapy in 14.7% of patients, and resulted in a new infection-related diagnosis unrelated to bacteremia in 9.8% of episodes. FDG-PET/CT had a high clinical impact in 47.3% of cases and was independent of duration of preceding antimicrobial treatment as well as number of days of bacteremia.