Jamar François, van der Laken Conny J, Panagiotidis Emmanouil, Steinz Maarten M, van der Geest Kornelis S M, Graham Richard N J, Gheysens Olivier
Department of Nuclear Medicine, Cliniques universitaires St-Luc and Institute for Experimental and Clinical Research (IREC), Université Catholique de Louvain, Brussels, Belgium.
Department of Rheumatology, Amsterdam University Medical Center - location VU Medical Center, Amsterdam, The Netherlands.
Semin Nucl Med. 2023 Mar;53(2):287-300. doi: 10.1053/j.semnuclmed.2022.08.010. Epub 2022 Sep 23.
Arthritis and other rheumatic disorders are very frequent in the general population and responsible for a huge physical and disability burden to affected patients as well as a major cost to the society. Precise evaluation often relies on clinical data only but additional imaging may be required i) for a more objective assessment of the disease status, such as in rheumatoid arthritis (RA) or ankylosing spondyloarthritis (AS), ii) for providing prognostic information and evaluating response to treatment or iii) for establishing diagnosis, in patients with unclear clinical picture, such as polymyalgia rheumatica (PMR) and large-vessel vasculitis (LVV). Besides radiological techniques (x-rays, ultrasound, and MRI), functional and molecular imaging has emerged as a valid tool for this purpose in several disorders. Bone scanning has long been a method of choice but is now more used as a triage tool in patients with unclear complaints, including degenerative disorders (eg osteoarthritis). F-FDG-PET/CT (FDG) proved efficient in assessing the extent of the disease and response to treatment in RA and related disorders, and to provide accurate diagnosis in some systemic disorders, including PMR and LVV. Based on glucose metabolism, FDG-PET/CT is able to show increased metabolism in peripheral cells involved in inflammation (eg neutrophils, lymphocytes or monocytes/macrophages) but also in fibroblasts that proliferate in the pannus. The lack of specificity of FDG is a limitation and many alternative tracers were developed at the preclinical stage or applied in the clinics, especially within clinical trials. They include imaging of macrophages using translocator protein (TSPO), folate-receptors or other targets on activated cells. These new tools will undoubtedly become more and more available in the everyday clinical workup of patients with rheumatisms. Finally, it should be kept in mind that a very simple tracer, F-fluoride is widely more performant in AS than FDG.
关节炎和其他风湿性疾病在普通人群中非常常见，给受影响的患者带来了巨大的身体负担和残疾负担，也给社会造成了重大成本。精确评估通常仅依赖临床数据，但对于以下情况可能需要额外的影像学检查：i）更客观地评估疾病状态，如类风湿关节炎（RA）或强直性脊柱炎（AS）；ii）提供预后信息并评估对治疗的反应；iii）对于临床表现不明确的患者，如风湿性多肌痛（PMR）和大血管血管炎（LVV），用于确立诊断。除了放射学技术（X线、超声和MRI）外，功能和分子成像已成为几种疾病中用于此目的的有效工具。骨扫描长期以来一直是一种首选方法，但现在更多地用作有不明主诉患者（包括退行性疾病，如骨关节炎）的分诊工具。F-FDG-PET/CT（FDG）已被证明在评估RA及相关疾病的疾病范围和对治疗的反应方面有效，并能在包括PMR和LVV在内的一些全身性疾病中提供准确诊断。基于葡萄糖代谢，FDG-PET/CT能够显示参与炎症的外周细胞（如中性粒细胞、淋巴细胞或单核细胞/巨噬细胞）以及在血管翳中增殖的成纤维细胞代谢增加。FDG缺乏特异性是一个局限性，许多替代示踪剂在临床前阶段就已开发或应用于临床，特别是在临床试验中。它们包括使用转位蛋白（TSPO）、叶酸受体或活化细胞上的其他靶点对巨噬细胞进行成像。这些新工具无疑将在风湿病患者的日常临床检查中越来越普及。最后，应牢记，一种非常简单的示踪剂F-氟化物在AS中比FDG表现得更为出色。
