Of these, 35/53 (66%) of the patients had positive FDG-PET/CT findings, and 13/53 (25%) of the 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%). The presence of liver cirrhosis was the only variable significantly associated with the likelihood of negative PET data (P = . 005). 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 the patients had positive FDG-PET/CT findings, of whom 3/18 (17%) of the patients were false positives, 11/18 (61%) of the patients were true positives, and 6/18 (33%) of the 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 the 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 the duration of the preceding antimicrobial treatment as well as the number of days of bacteremia.
Sepsis. Of these, 35/53 (66%) of the patients had positive FDG-PET/CT findings, and 13/53 (25%) of the 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%). The presence of liver cirrhosis was the only variable significantly associated with the likelihood of negative PET data (P = . 005). 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 the patients had positive FDG-PET/CT findings, of whom 3/18 (17%) of the patients were false positives, 11/18 (61%) of the patients were true positives, and 6/18 (33%) of the 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 the 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 the duration of the preceding antimicrobial treatment as well as the number of days of bacteremia.