Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2025 Apr 30;15(1):51.
doi: 10.1186/s13550-025-01233-7.

Whole-body and site specific [18F]FDG uptake patterns on PET/CT have limited value in differentiating between polymyalgia rheumatica and other inflammatory diseases: two cohorts of treatment-naïve suspected polymyalgia rheumatica

Andreas Wiggers Nielsen  1   2   3 , Gijs D van Praagh  4 , Kornelis S M van der Geest  5 , Ib Tønder Hansen  6   7 , Berit Dalsgaard Nielsen  6   7   8 , Søren Geill Kjær  9 , Jesper Blegvad-Nissen  9 , Kate Rewers  10 , Christian Møller Sørensen  8 , Elisabeth Brouwer  5 , Ellen-Margrethe Hauge  6   7 , Lars Christian Gormsen  7   11 , Riemer H J A Slart  4   12 , Kresten Krarup Keller  6   7
Affiliations

Whole-body and site specific [18F]FDG uptake patterns on PET/CT have limited value in differentiating between polymyalgia rheumatica and other inflammatory diseases: two cohorts of treatment-naïve suspected polymyalgia rheumatica

Andreas Wiggers Nielsen et al. EJNMMI Res. .

Abstract

Background: It has been hypothesized that 2-[18F]fluoro-2-deoxy-D-glucose ([18F]FDG) positron emission tomography (PET) computed tomography (CT) can distinguish polymyalgia rheumatica (PMR) from non-PMR patients based on the [18F]FDG-uptake patterns. Nevertheless, a comprehensive assessment of whole-body [18F]FDG-patterns across all uptaking musculoskeletal sites, as well as site-specific [18F]FDG-uptake patterns, has not been conducted. Therefore, this study aimed to investigate both the overall whole-body [18F]FDG-uptake patterns and the specific uptake patterns at individual sites in patients suspected of having PMR.

Methods: Two distinct cohorts of patients with suspected PMR from Denmark and the Netherlands were prospectively included, encompassing 66/27 and 36/21 PMR/non-PMR patients, respectively. The cohorts consisted of treatment-naïve patients, who underwent pre-treatment [18F]FDG-PET/CT scans. The [18F]FDG-uptake was then assessed across 34 different anatomical sites. Furthermore, the site-specific [18F]FDG-uptake pattern within each anatomical site was categorized according to its shape.

Results: Patients with PMR were more likely than non-PMR patients to have bilateral [18F]FDG-uptake equal to or above liver compared at the ischial tuberosities (91%/41%), shoulder joints (86%/45%), hip joints (83%/52%), and along the lumbar spinal processes (70%/30%). However, a subgroup analysis comparing non-PMR patients with other inflammatory conditions to patients with PMR revealed that several non-PMR patients exhibited a similar whole-body [18F]FDG-uptake pattern. Furthermore, site-specific [18F]FDG-uptake patterns were similar in patients with PMR and non-PMR.

Conclusion: Assessing whole-body or site-specific [18F]FDG-uptake patterns does not improve the diagnostic accuracy in distinguishing PMR from other inflammatory diseases. Consequently, [18F]FDG-PET/CT should mainly be used to rule out a clinical diagnosis of PMR.

Trial registration: ClinicalTrials.gov (NCT04519580). Registered 17th of August 2020.

Keywords: Diagnostic imaging; FDG-PET/CT; Pattern recognition; Polymyalgia rheumatica.

PubMed Disclaimer

Conflict of interest statement

Declarations. Ethics approval and cosent to participate: This study complies with the Declaration of Helsinki. The study protocol for the Danish cohort was approved by the Regional Scientific Ethical Committee for the Central Denmark Region (reference number 1-10-72-99-19) and the Internal List of Research Projects in Central Denmark Region—former Danish Data Protection Agency (reference number: 1-16-02-166-19). All patients provided written informed consent. The study protocol for the Dutch cohort was approved by the ethics committee of the University Medical Center Groningen (METc 2020/220). Consent for publication: Informed written consent was obtained from all individual participants included in the Danish cohort, including the patients depicted in Fig. 1. Informed consent was not required for the Dutch cohort due to the retrospective design of the study. Competing interests: AWN, GP, ITH, SGK, JB-N, CMS, KR, LCG, EB and KK have nothing to declare. BDN has received speaking fees unrelated to this manuscript from Novartis and AbbVie. EMH has received grants unrelated to this manuscript from Novo Nordic Foundation, Roche, Novartis and personal fees from AbbVie, Sanofi, SOBI, Merck Sharp & Dohme and Union Chimique Belge. KG reports speaking fee from Roche and research support from AbbVie and Siemens paid to the UMCG, outside the submitted work. RS received unrestricted research grants from Siemens Healthineers and Pfizer. Furthermore, RS serves as an editor for EJNMMI.

Figures

Fig. 1
Fig. 1
Different [18F]FDG-uptake patterns in the shoulder joints are displayed graphically and on PET scans. A Whole-body PET scan of a patient with PMR. Focal [18F]FDG uptake in the right shoulder and cylindrical [18F]FDG uptake in the left shoulder equal to liver uptake (grade 2). B Whole-body PET scan of a patient with PMR. Circular [18F]FDG uptake in the right shoulder equal to liver uptake (grade 2) and high [18F]FDG uptake in the left should above liver (grade 2), displaying a focal and circular pattern. C Whole-body PET scan of a patient with rheumatoid arthritis. High focal and circular [18F]FDG uptake (grade 2) above liver uptake in both shoulders. In addition, this patient exhibits high [18F]FDG uptake above liver in the elbow, wrist and finger joints. Blue arrows mark focal uptake, orange arrow marks cylindrical uptake, and green arrows mark circular uptake. [18F]FDG, 2-[18 F]fluoro-2-deoxy-D-glucose; PET, Positron emission tomography; PMR, Polymyalgia rheumatica
Fig. 2
Fig. 2
Proportion of suspected PMR patients with avid symmetrical [18F]FDG-uptake—Danish cohort. A Bar plot displaying the proportion of patients with bilateral [18F]FDG uptake above liver for symmetrical sites (visual summed score of 4) and [18F]FDG uptake above liver in singular sites among patients with PMR and non-PMR. B Bar plot displaying the proportion of patients with bilateral [18F]FDG uptake above liver for symmetrical sites (visual summed score of 4) and [18F]FDG uptake above liver in singular sites among PMR and non-PMR patients with other inflammatory conditions. [18F]FDG, 2-[18 F]fluoro-2-deoxy-D-glucose; PMR, Polymyalgia rheumatica
Fig. 3
Fig. 3
Proportion of suspected PMR patients with avid symmetrical [18F]FDG-uptake—Dutch cohort. A Bar plot displaying the proportion of patients with bilateral [18F]FDG uptake above liver for symmetrical sites (visual summed score of 4) and [18F]FDG uptake above liver in singular sites among patients with PMR and non-PMR. B Bar plot displaying the proportion of patients with bilateral [18F]FDG uptake above liver for symmetrical sites (visual summed score of 4) and [18F]FDG uptake above liver in singular sites among PMR and non-PMR patients with other inflammatory conditions. [18F]FDG, 2-[18 F]fluoro-2-deoxy-D-glucose; PMR, Polymyalgia rheumatica
See this image and copyright information in PMC

Similar articles

See all similar articles

References

    1. Gonzalez-Gay MA, Garcia-Porrua C, Salvarani C, Olivieri I, Hunder GG. The spectrum of conditions mimicking polymyalgia rheumatica in Northwestern Spain. J Rheumatol. 2000;27:2179–84. - PubMed
    1. Owen CE, Buchanan RR, Hoi A. Recent advances in polymyalgia rheumatica. Intern Med J. 2015;45:1102–8. 10.1111/imj.12823. - PubMed
    1. Paltta J, Suuronen S, Pirilä L, Palomäki A. Differential diagnostics of polymyalgia rheumatica in a university hospital in Finland. Scand J Rheumatol. 2023:1–7. 10.1080/03009742.2023.2215044. - PubMed
    1. Sondag M, Guillot X, Verhoeven F, Blagosklonov O, Prati C, Boulahdour H, et al. Utility of 18F-fluoro-dexoxyglucose positron emission tomography for the diagnosis of polymyalgia rheumatica: a controlled study. Rheumatology (Oxford). 2016;55:1452–7. 10.1093/rheumatology/kew202. - PubMed
    1. Owen CE, Poon AMT, Yang V, McMaster C, Lee ST, Liew DFL, et al. Abnormalities at three musculoskeletal sites on whole-body positron emission tomography/computed tomography can diagnose polymyalgia rheumatica with high sensitivity and specificity. Eur J Nucl Med Mol Imaging. 2020;47:2461–8. 10.1007/s00259-020-04731-z. - PubMed

Associated data

LinkOut - more resources