Diagnosing fevers of unknown origin can be tricky and time consuming but new research published in Scientific Reports suggests that F-18 FDG PET/CT could be of value when other imaging modalities do not produce sufficient results.
Fevers are common but when they persist for three weeks or more despite treatment efforts, their origin becomes a more serious concern. The two most common reasons for fever of unknown origin (FUO) are infection and malignancy but there are hundreds of other possibilities that are less severe. Finding the underlying cause involves an extensive workup that includes physical examination, laboratory testing and medical imaging.
Since plain radiographs, ultrasound, CT and other modalities can sometimes yield inconclusive results, researchers hypothesized that F-18 FDG PET/CT could help fill in some of the blanks.
“Due to the high sensitivity of detecting early metabolic changes, F-18 FDG PET/CT represents the modality of choice in clinical management especially when other imaging modalities deliver inconclusive results,” corresponding author Friedrich Weitzer, with the Division of Nuclear Medicine at the Medical University of Graz, and coauthors explained.
To test their theory, experts retrospectively examined the cases of 300 men and women with FOU at a single center. When the patients’ PET/CT findings were compared to their reported final outcomes it was revealed that the scan results determined the final diagnosis in 54% of cases.
This resulted in a sensitivity of 80.2% and a specificity of 89.8%, respectively. The PET/CT results led to new treatment plans for 24% of patients and altered treatments in 18% of cases.
“Our study clearly showed an overall high sensitivity and specificity compared to several meta-analyses,” the experts wrote. “Therefore, the early use of F-18 FDG PET/CT should be considered if other diagnostic means fail.”
The researchers note that although their study indicates that F-18 FDG PET/CT is a valuable diagnostic resource, making it the standard for the first-line work-up for FUO patients could be challenging.
You can view the detailed research here.
In addition to her background in journalism, Hannah also has patient-facing experience in clinical settings, having spent more than 12 years working as a registered rad tech. She joined Innovate Healthcare in 2021 and has since put her unique expertise to use in her editorial role with Health Imaging.