RESUMO
This study observed the image characteristics and clinico-imaging relationships of (18)F-fluorodeoxyglucose positron emission tomography/computed tomography ((18)F-FDG PET/CT) in the patients with Kikuchi-Fujimoto disease (KFD). Nine consecutive patients with histologically proven KFD who underwent (18)F-FDG PET/CT were recruited. The (18)F-FDG uptakes of bone marrow (BM), spleen and lymph nodes (LNs) were systematically evaluated and maximum standardized uptake values (SUVmax) were measured. The number, locations and size factors of LNs were also assessed. The correlations were calculated between (18)F-FDG uptake and laboratory data and size factors of LNs, and the findings of LNs were compared between subgroups with different clinical features. (18)F-FDG uptakes were positive in the BM (SUVmax, 3.2 ± 1.2), spleen (SUVmax, 2.8 ± 0.7) and 122 affected LNs (SUVmax, 4.2 ± 2.2) for all patients. The affected LNs presented a systemically (region, 4 ± 1), multiple (number, 14 ± 5) and small-sized (long axis diameter, 11.4 ± 2.7 mm; short axis diameter, 8.0 ± 2.1 mm; area, 81.1 ± 44.6 mm(2)) pattern. The SUVmax of BM correlated to neutrophil count, and the SUVmax of affected LNs correlated to size factors and was lower in patients with long imaging interval and positive anti-nuclear antibody (ANA) (P < 0.05). We conclude that (18)F-FDG PET/CT can be characterized by the generalized distribution of relatively small-sized LNs and involvement of BM and spleen with high (18)F-FDG avidity in patients with KFD. The imaging interval, neutrophil count and ANA level should be synthetically considered during imaging evaluation.
RESUMO
18-Fluoredeoxyglucose position emission tomography and computed tomography ((18)F-FDG PET/CT) scanning has been widely used in the assessment of malignancy. We report here an increased (18)F-FDG uptake in pleural nodules in the PET/CT scan images of a patient having recurrent fever and chest pain. Further studies with bacterial culture and histopathology of biopsy confirmed the lesions as nocardial infection. To our knowledge, it is the first report of PET /CT findings in pleural multiple irregular nodules with nocardial infection. Our study suggests that a combination of FDG-PET/CT scanning and pathological study may be considered in distinguishing uncommon benign lesions in the lung.