Clinical and laboratory predictors of diagnostic efficacy of 18F-FDG PET/CT in rheumatology: a retrospective tertiary-centre study
Rheumatology International, cilt.46, sa.6, 2026 (SCI-Expanded, Scopus)
- Yayın Türü: Makale / Tam Makale
- Cilt numarası: 46 Sayı: 6
- Basım Tarihi: 2026
- Doi Numarası: 10.1007/s00296-026-06192-3
- Dergi Adı: Rheumatology International
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, BIOSIS, EMBASE, MEDLINE, Academic Search Ultimate (EBSCO), Biomedical Reference Collection: Corporate Edition (EBSCO), Health Research Premium Collection (ProQuest), Pharma Collection (ProQuest)
- Anahtar Kelimeler: PET-CT scan, Positron emission tomography-computed tomography, Lactate dehydrogenase, Fluorodeoxyglucose F18, Malignancy, Vasculitis
- Sağlık Bilimleri Üniversitesi Adresli: Evet
Özet
Objectives: The aim of this study was to evaluate the diagnostic value of 2-[¹⁸F]-fluoro-2-deoxy-d-glucose positron emission tomography/computed tomography (¹⁸F-FDG PET/CT) in rheumatology, identifying clinical and laboratory predictors of significant findings in patients with ambiguous aetiologies or established rheumatic diseases. Methods: A retrospective analysis was conducted on 128 patients (Group A: n = 60; etiological investigation; Group B: n = 68; established rheumatic diseases) who underwent 18F-FDG PET/CT. Independent predictors were identified via multivariate logistic regression analysis. The diagnostic performance was assessed using a receiver operating characteristic (ROC) analysis and compared using the DeLong test. Results: ¹⁸F-FDG PET/CT scans were helpful in reaching a final diagnosis in 53.9% (n = 69) of patients. The most common diagnoses were malignancy (26%, n = 18), flare-ups (18.8%, n = 13), localized inflammatory findings (17.4%, n = 12), and vasculitis (13%, n = 9). Multivariate analysis identified symptom duration (Group A: odds ratio [OR] = 1.86, p < 0.001; Group B: OR = 2.64, p = 0.004) and lactate dehydrogenase (LDH) levels (per 10 U/L increase; Group A: OR = 1.64, p = 0.001; Group B: OR = 2.99, p = 0.015) as independent predictors. ROC analysis, with cut-off determined by the Youden index, showed that LDH > 251.5 U/L (AUC: 0.888) and symptom duration > 7.45 weeks (AUC: 0.841) had high accuracy in Group A. Group B demonstrated even greater predictive power for symptom duration > 7.31 weeks (AUC: 0.945) and LDH > 264 U/L (AUC: 0.927) (p < 0.001). DeLong’s test confirmed that LDH and symptom duration provided similar diagnostic value, with no significant difference in their AUC values between Groups A and B (p = 0.551 and p = 0.670, respectively). Conclusion: ¹⁸F-FDG PET/CT is a valuable diagnostic tool in rheumatology, particularly for detecting occult malignancies and vasculitis. Symptom duration > 7 weeks and elevated LDH levels are significant, independent predictors of diagnostic yield, potentially optimising patient selection for molecular imaging.