Impact of 18 F-FDG-PET/CT on the management of Staphylococcus aureus bacteraemia: a retrospective observational study.

OBJECTIVES: To assess the impact of 18 F-FDG-PET/CT on the diagnosis and management of patients with Staphylococcus aureus bacteraemia (SAB).

METHODS: Post hoc analysis of a prospective cohort of consecutive adult patients diagnosed with SAB (January 2013-December 2017). Patients who underwent 18 F-FDG-PET/CT at the discretion of the attending physician were included. Endpoints were the identification of previously unknown infectious foci and changes in clinical management, defined as changes in the duration or class of antibiotic therapy, a surgical procedure on the source of infection or a change in the decision to remove or retain an implantable device.

RESULTS: We included 39 patients (median age: 69 years, IQR:60-79). Fifteen (39%) patients did not have an infectious focus identified before 18 F-FDG-PET/CT). Thirty new infectious foci were detected in 22/39 (56%) patients. In 11/15 (73%) patients without an identified focus at least one infectious focus was detected by 18 F-FDG-PET/CT. In 22/26 (85%) patients with implantable devices, 18 F-FDG-PET/CT confirmed or ruled out infection or detected local complications. Out of 13 device infections, 10 were detected by 18 F-FDG-PET/CT (7/10 for the first time). In 19/39 (49%) patients 18 F-FDG-PET/CT results led to changes in clinical management (15 changes in antibiotic therapy, 2 device removals, 2 surgical procedures, 1 avoidance of a surgical procedure).

CONCLUSIONS: 18 F-FDG-PET/CT may be a useful asset in the management of selected SAB cases, allowing the identification of previously undetected infectious foci and optimization of therapy, particularly in patients with endovascular devices. Indication should be made on a case-by-case basis.