Fig. 1
Whole-body PET image (a) and axial hybrid PET/CT images of the axillary LNs (b), liver and spleen (c), and pelvis bone (d) from a 45-year-old female patient with fever, skin rash, and arthralgia showed increased 18F-FDG uptake by the right axillary LNs (SUVmax, 6.7), spleen (SUVmax, 4.7), liver (SUVmax, 3.3), and pelvic bone marrow (SUVmax, 4.3). The TLGtotal of LNs was 199,697.4, and MLVtotal of LNs was 53.88. The patient did not progress to MAS after glucocorticoids and methotrexate treatment. Another 42-year-old female patient with fever, skin rash, and lymphadenopathy showed increased 18F-FDG uptake by the left axillary LNs (SUVmax, 9.8), mediastinum LNs (SUVmax, 11.4), spleen (SUVmax, 7.5), liver (SUVmax, 4.7), and pelvic bone marrow (SUVmax, 5.1) on whole-body PET image (e) and axial hybrid PET/CT images of the axillary and mediastinum LNs (f), liver and spleen (g), and pelvis bone (h). The TLGtotal of LNs was 1,144,469.8, and MLVtotal of LNs was 244.75. The patient progressed to MAS after glucocorticoid treatment. Lately, she received intravenous immunoglobulins and achieved remission. LNs, lymph nodes; SUV, standardized uptake value; TLG, total lesion glycolysis; MLV, metabolic lesion volume; MAS, macrophage activation syndrome