Reddy Natasha, Raynor William Y, Werner Thomas J, Baker Joshua F, Alavi Abass, Revheim Mona-Elisabeth
Department of Radiology, Hospital of the University of Pennsylvania, 3400 Spruce Street, Philadelphia, PA 19104, USA.
Division of Rheumatology, University of Pennsylvania, 3400 Spruce Street, Philadelphia, PA 19104, USA.
Diagnostics (Basel). 2023 Jun 23;13(13):2149. doi: 10.3390/diagnostics13132149.
Rheumatoid arthritis (RA) involves chronic inflammation of synovial joints, causing pain, stiffness, and limited mobility. F-sodium fluoride (NaF) is a PET tracer whose uptake reflects bone turnover, while F-fludeoxyglucose (FDG) shows glucose metabolism and can serve as a marker for inflammation. The aim of this study is to determine the feasibility of calculating the FDG and NaF mean standardized uptake value (SUVmean) in the knee joint, hip joint, and sacroiliac (SI) joint of RA patients and to determine their association with patient characteristics. Prospective FDG-PET/CT as well as NaF-PET/CT imaging was performed on 18 RA patients. The global SUVmean was calculated on FDG-PET/CT and NaF-PET/CT images using a semiautomated CT-based method of segmentation. FDG and NaF uptake were found to be significantly correlated in the knee (r = 0.77, < 0.001), but not in the hip and SI joints. In the knee, both NaF SUVmean and FDG SUVmean were significantly correlated with body weight, BMI, leptin, and sclerostin levels ( < 0.05). NaF SUVmean was significantly positively correlated with BMI and leptin for both the hip and SI joints ( < 0.05). No significant correlation was observed between either PET parameter and age, height, erythrocyte sedimentation rate (ESR), and interleukins 1 and 6 (IL-1 and IL-6); however, FDG was correlated with inflammatory markers such as C-reactive protein (CRP) and patient global visual analogue scale (VAS-PtGlobal) in some joints. In this study, both FDG and NaF uptake were quantified in large joints of patients with RA using CT segmentation. NaF and FDG SUVmean were correlated with clinical variables related to body weight and adiposity, suggesting that degenerative joint disease may play a larger role in influencing the uptake of these tracers in large joints than RA disease activity. FDG and its correlation with markers of inflammation such as CRP and VAS-PtGlobal suggests that this tracer may serve as a more specific marker for RA disease activity than NaF. Larger prospective and longitudinal data are necessary to gain a better understanding of the roles of FDG and NaF in evaluating RA joint activity in these joints.
类风湿性关节炎（RA）涉及滑膜关节的慢性炎症，会导致疼痛、僵硬和活动受限。氟代氟化钠（NaF）是一种正电子发射断层显像（PET）示踪剂，其摄取反映骨转换，而氟代脱氧葡萄糖（FDG）显示葡萄糖代谢，可作为炎症标志物。本研究的目的是确定计算RA患者膝关节、髋关节和骶髂（SI）关节中FDG和NaF平均标准化摄取值（SUVmean）的可行性，并确定它们与患者特征的关联。对18例RA患者进行了前瞻性FDG-PET/CT以及NaF-PET/CT成像。使用基于CT的半自动分割方法在FDG-PET/CT和NaF-PET/CT图像上计算整体SUVmean。发现膝关节中FDG和NaF摄取显著相关（r = 0.77，<0.001），但髋关节和SI关节中不相关。在膝关节中，NaF SUVmean和FDG SUVmean均与体重、体重指数（BMI）、瘦素和硬化蛋白水平显著相关（<0.05）。NaF SUVmean在髋关节和SI关节中均与BMI和瘦素显著正相关（<0.05）。未观察到任何PET参数与年龄、身高、红细胞沉降率（ESR）以及白细胞介素1和6（IL-1和IL-6）之间存在显著相关性；然而，在某些关节中，FDG与C反应蛋白（CRP）和患者整体视觉模拟评分（VAS-PtGlobal）等炎症标志物相关。在本研究中，使用CT分割对RA患者的大关节中的FDG和NaF摄取进行了量化。NaF和FDG SUVmean与与体重和肥胖相关的临床变量相关，这表明退行性关节疾病在影响这些示踪剂在大关节中的摄取方面可能比RA疾病活动起更大作用。FDG及其与CRP和VAS-PtGlobal等炎症标志物的相关性表明，与NaF相比，这种示踪剂可能是RA疾病活动的更特异性标志物。需要更大规模的前瞻性和纵向数据，以更好地了解FDG和NaF在评估这些关节中RA关节活动中的作用。
