Clinical implications of increased uptake in bone marrow and spleen on FDG-PET in patients with bacteremia

Jordy P Pijl; Thomas C Kwee; Riemer H J A Slart; Derya Yakar; Marjan Wouthuyzen-Bakker; Andor W J M Glaudemans

doi:10.1007/s00259-020-05071-8

Clinical implications of increased uptake in bone marrow and spleen on FDG-PET in patients with bacteremia

Eur J Nucl Med Mol Imaging. 2021 May;48(5):1467-1477. doi: 10.1007/s00259-020-05071-8. Epub 2020 Oct 26.

Authors

Jordy P Pijl¹, Thomas C Kwee², Riemer H J A Slart^{2

3}, Derya Yakar², Marjan Wouthuyzen-Bakker⁴, Andor W J M Glaudemans²

Affiliations

¹ Medical Imaging Center, Departments of Radiology, Nuclear Medicine and Molecular Imaging, University Medical Center Groningen, University of Groningen, Hanzeplein 1, P.O. Box 30.001, 9700 RB, Groningen, The Netherlands. j.p.pijl@umcg.nl.
² Medical Imaging Center, Departments of Radiology, Nuclear Medicine and Molecular Imaging, University Medical Center Groningen, University of Groningen, Hanzeplein 1, P.O. Box 30.001, 9700 RB, Groningen, The Netherlands.
³ TechMed Centre, Department of Biomedical Photonic Imaging, University of Twente, Enschede, The Netherlands.
⁴ Department of Medical Microbiology and Infection Prevention, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands.

Abstract

Purpose: To investigate which clinical factors and laboratory values are associated with high FDG uptake in the bone marrow and spleen on 2-deoxy-2-[18F]fluoro-D-glucose (FDG) positron emission tomography (PET)/computed tomography (CT) in patients with bacteremia.

Methods: One hundred forty-five consecutive retrospective patients with bacteremia who underwent FDG-PET/CT between 2010 and 2017 were included. Mean standard uptake values (SUV_mean) of FDG in bone marrow, liver, and spleen were measured. Bone marrow-to-liver SUV ratios (BLR) and spleen-to-liver SUV ratios (SLR) were calculated. Linear regression analyses were performed to examine the association of BLR and SLR with age, gender, hemoglobin, leukocyte count, platelets, glucose level, C-reactive protein (CRP), microorganism, days of antibiotic treatment before FDG-PET/CT, infection focus, use of immunosuppressive drugs, duration of hospital stay (after FDG-PET/CT), ICU admission, and mortality.

Results: C-reactive protein (p = 0.006), a cardiovascular or musculoskeletal focus of infection (p = 0.000 for both), and bacteremia caused by Gram-negative bacteria (p = 0.002) were independently and positively associated with BLR, while age (p = 0.000) and glucose level before FDG-PET/CT (p = 0.004) were independently and negatively associated with BLR. For SLR, CRP (p = 0.001) and a cardiovascular focus of infection (p = 0.020) were independently and positively associated with SLR, while age (p = 0.002) and glucose level before FDG-PET/CT (p = 0.016) were independently and negatively associated with SLR.

Conclusion: High FDG uptake in the bone marrow is associated with a higher inflammatory response and younger age in patients with bacteremia. In patients with high FDG uptake in the bone marrow, a cardiovascular or musculoskeletal focus of infection is more likely than other foci, and the infection is more often caused by Gram-negative species. High splenic FDG uptake is associated with a higher inflammatory response as well, and a cardiovascular focus of infection is also more likely in case of high splenic FDG uptake.

Keywords: Bacteremia; Bone marrow; FDG; Sepsis; Spleen; Uptake.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Bacteremia* / diagnostic imaging
Bone Marrow / diagnostic imaging
Fluorodeoxyglucose F18*
Glucose
Humans
Positron Emission Tomography Computed Tomography
Positron-Emission Tomography
Radiopharmaceuticals
Retrospective Studies
Spleen / diagnostic imaging

Substances

Radiopharmaceuticals
Fluorodeoxyglucose F18
Glucose