IgG4 related diseases:whole-body 18 F-FDG PET/CT findings

FENG Fei; YU Zhong-fei; ZHANG Jian; YANG Jian; HU Sheng-ping; SUN Gao-feng; CHENG Chao; DONG Ai-sheng; KONG Ling-shan; ZUO Chang-jing

Abstract：Objective To analyze the PET/CT imaging characteristics of IgG4 related diseases (IgG4 related diseases , IgG4RD) and to investigate the function of 18 F-FDG PET/CT in diagnosing of IgG4RD and whole-body evaluation .Meth-ods Whole-body 18 F-FDG PET /CT findings in 14 patients (male 12 ,female 2 ,age from 43 to 75 ,the median age of 59 years old) with clinical conformed IgG4RD were reviewed retrospectively .Organs'morphology changes ,density alter and 18 F-FDG metabolism were observed .Results All of 14 cases had a high level of serum IgG4 ,(970 .14 ± 950 .70) mg/dl (136~3690) mg/dl .18 F-FDG PET/CT imaging showed that there were multiple organ involvement in IgG4RD and 12 ca-ses (85 .7% ) with pancreas involvement ,which were characterized by diffuse or segmental enlargement of the pancreas with increased 18 F-FDG uptake;9 cases (62 .3% ) with salivary gland involvement were characterized by unilateral or bilat-eral salivary glands swelling with increased 18 F-FDG uptake;6 cases (42 .9% ) had bile duct system involved ,which were characterized by mild expansion of bile ducts with mild thickening wall .Along the bile duct ,18 F-FDG uptake was in-creased;7 in 12 male patients (58 .3% ) had prostatic involved characterized by unilateral or bilateral lobe with increased 18 F-FDG uptake;Other organs were involved ,including thyroid (5 cases) ,lung (4 cases) ,intestine (4 cases) ,artery (2 cases) and kidney (1 case) .Conclusion IgG4RD is a systemic disease .18 F-FDG PET/CT shows well the changes and metabolic characteristics of organs ,which are involved in IgG4RD .It plays a distinct role in diagnosis of IgG4RD and w hole-body evaluation .