Effects of Fever on 18F-FDG Distribution In Vivo: a Preliminary Study

Abstract

Purpose: Elevated body temperature might change glucose metabolism in human organs. The purpose of this study is to explore 18 F-FDG distribution in febrile patients on the day of 18 F-FDG PET/CT scanning and compare it with patients with a normal temperature. Procedures: 18 F-FDG PET/CT was performed on 69 febrile patients and 82 patients with a normal temperature. Patient sociodemographic data, blood glucose levels before PET/CT, body temperature on the day of the exam, and laboratory test results were collected. Maximal standard uptake values (SUV max ) in the brain, mediastinal blood pool, liver, spleen, and the bone marrow were compared. Results: Compared with the controls, SUV max of the febrile patients was significantly lower in the brain, mediastinal blood pool, and the liver (p G 0.01), and higher in the spleen and bone marrow (p G 0.01). In the febrile group, SUV max was not significantly different between the FDG burden and non-FDG burden patients (p 9 0.05). Body temperature was found negatively correlated with SUV max in the brain (r = − 0.646), mediastinal blood pool (r = − 0.530), and the liver (r = − 0.384), and positively correlated with the SUV max in the spleen (r = 0.592) and bone marrow (r = 0.651). Multivariate linear regression established body temperature on the day of PET/CT as an independent affecting factor (p G 0.01) for the SUV max in the brain, mediastinal blood pool, liver, spleen, and bone marrow. The SUV in the brain, liver, and mediastinal blood pool remained different (p G 0.05) after corrected with the SUV max in the blood pool or liver. Conclusions: Fever influences 18 F-FDG distribution in multiple human tissues and organs. Altered 18 F-FDG distribution in vivo might affect results of disease lesion detection and tumor therapy response assessment. Correction with blood pool or liver SUV fails to cancel the effects of fever. The day of fever should be avoided for PET/CT scan, especially in assessing tumor therapy response.

Role of splenic and bone marrow uptake at 18F‐FDG PET/CT for the assessment of large vessels vasculitis and the influence of glucocorticoids therapy on their values

“…These findings underline again the correlation of both BM and splenic uptake in cases of systemic inflammation. In this scenario, a correlation between splenic and BM uptake with CRP has also been reported when focusing on patients with fever 14 . Furthermore, Rosenblum et al 15 .…”

“…when focusing on patients with fever. 14 Furthermore, Rosenblum et al 15 reported a positive significant correlation for 18 F-FDG splenic uptake and CRP both at 1 and 2 h PET/CT scans, focusing only on LVV in a time-specific setting.…”

“…11 It is known that splenic and bone marrow (BM) uptake at 18 F-FDG PET/CT in active autoimmune febrile disorders is increased and that spleen uptake can be helpful to assess disease activity in systemic inflammatory diseases, such as LVV. [14][15][16] Therefore, the aim of this study was to assess the presence of a relationship between splenic and BM uptake with the presence of LVV at 18 F-FDG PET/CT. Furthermore, the influence of GC on such uptakes was also investigated.…”

Membrane‐destabilizing ionizable lipid empowered imaging‐guided siRNA delivery and cancer treatment

“…Magnetic resonance imaging (MRI) has the capability to visualize the three‐dimensional structure of tissue due to high spatial resolution and deep tissue penetration without radiation. [ 10 ] However, the sensitivity of MRI is relatively poor compared with positron emission tomography (PET) [ 11 ] and optical imaging, [ 12 ] resulting in a weak contrast resolution in distinguishing tumors from adjacent normal tissues. [ 13 ] Two strategies can be used to circumvent these limitations: (1) develop a nano‐system that can load high amount of magnetic resonance contrast agents, and (2) enhance the accumulation of magnetic nanoparticles in the tumor via an active targeting process, such as by employing a receptor‐ligand interaction mechanism during the delivery process.…”