The significance of ¹⁸F-FDG PET/CT in secondary hemophagocytic lymphohistiocytosis

This study was aimed to investigate the significance of ¹⁸F-FDG PET/CT in secondary hemophagocytic lymphohistiocytosis (sHLH) patients. A total of 18 patients received ¹⁸F-FDG PET/CT scan at initial diagnosis. All patients (18/18) had at least 3 organs involved, with increased FDG metabolism in different degrees. Fifteen cases (15/18) had definite underlying diseases, including infections (IAHLH), rheumatosis (RAHLH), or malignancy (MAHLH). The SUV_max of patients in MAHLH group was significantly higher than patients in IAHLH group or RAHLH group (P = 0.015, P = 0.045). Furthermore, the SUV_max of patients in IAHLH group was significantly higher than patients of RAHLH group (P = 0.043). Therefore, we concluded that ¹⁸F-FDG PET/CT may especially play important role in differential diagnosis of sHLH.