Supplement Article |
OP8. REPETITIVE 18-FLUORODEOXYGLUCOSE POSITRON EMISSION TOMOGRAPHY IN GIANT CELL ARTERITIS: A PROSPECTIVE STUDY IN 35 PATIENTS
1 Department of General Internal Medicine and 2 Department of Nuclear Medicine, University Hospital Gasthuisberg, Leuven, Belgium
Objective: To study fluorodeoxyglucose (FDG)-deposition in the different vascular beds and in the large joints of patients with giant-cell arteritis (GCA), at diagnosis and during steroid treatment.
Methods: All consecutive patients admitted to our department with a diagnosis of GCA underwent FDG-positron emission tomography (PET) scan before treatment with methylprednisolone was started. PET-scans were repeated at 3 and 6 months, if the initial PET scans showed vascular FDG-uptake. PET-scans were scored at 7 different vascular areas and a total vascular score (TVS) was calculated, ranging from 0 to 21.
Results: 35 patients entered the study. At diagnosis, vascular FDG-uptake was noted in 29 patients (83%). There was no correlation between FDG findings and laboratory parameters or patients complaints, except for jaw claudication. FDG-uptake in the shoulders correlated significantly with the presence of polymyalgia rheumatica (p = 0.005). TVS decreased from a mean score of 7.9±5.5 at baseline to 2.4±3.5 on repeat PET scan at 3 months (p<0.0005) but did no further decrease at 6 months. The patients who had a relapse had similar decreases of TVS compared to those who did not relapse.
Conclusions: FDG-uptake in the large vessels is a sensitive marker for GCA, which can involve the larger thoracic, abdominal and peripheral arteries. Polymyalgia rheumatica complaints in GCA patients correlate with (peri)synovitis of the shoulders and not with inflammation of the subclavian or axillary arteries. Relapses of GCA cannot be predicted by results of former PET scintigraphies.