18 F-FDG PET/CT 在不明原因发热中的诊断价值

目的：评价18 F-FDG PET／CT显像在不明原因发热（ fever of unknown origin ，FUO）诊断中的临床价值。方法：回顾分析2010年8月至2013年4月的51例FUO病例的FDG PET／CT检查结果。依据病理学、实验室检查或临床随访（大于3个月）得出最终病因诊断，通过定性及半定量方法对FDG PET／CT的诊断结果进行评价，统计学分析采用组间t检验。结果：51例FUO患者的最终诊断包括感染32例、恶性肿瘤9例、非感染性炎症7例以及不明原因3例。单独FDG PET显像对FUO的诊断结果中，真阳性27例（52．9％），假阳性14例（27．5％），假阴性9例（17．6％），真阴性1例（2．0％）。相比之下，联合PET和CT检查的PET／CT显像诊断结果中，真阳性36例（70．6％），假阳性14例（27．5％），假阴性1例（2．0％），真阴性0例（0）。 PET／CT诊断的灵敏度为97．3％（36／37），特异性为0（0／14），准确度为70．6％（36／51）。针对恶性肿瘤，PET或PET／CT的诊断灵敏度及准确度均达100．0％（9／9）。感染与恶性肿瘤病灶的最大标准化摄取值（ maximum standardized uptake value ，SUVmax）之间差异有统计学意义（3．7±2．7 vs．7．7±3．5，P＝0．001，t＝3．6），提示SUVmax可能有助于发热病因的鉴别诊断。结论：FDG PET／CT不但能够在全身范围内发现、定位导致发热的潜在病灶，而且有助于FUO的病因诊断，特别是对恶性肿瘤的诊断。

Diagnostic value of fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography in fever of unknown origin

Objective: To evaluate the diagnostic value of fluorine-18 fluorodeoxyglucose ( 18 F-FDG) positron emission tomography/computed tomography ( PET/CT) in fever of unknown origin ( FUO) in a Chinese hospital .Methods:The records of 51 patients with FUO (32 men and 19 women;mean age 54 years with a range between 3 and 81 years) were analyzed retrospectively .All the patients were examined by 18 F-FDG PET/CT scan and the results were compared with the final diagnosis which was established by additional procedures including pathology , laboratory examination , and clinical follow-up for more than 3 months.The t test was used for statistical analysis .Results: A final diagnosis was established for 48 patients , including 32 patients with infectious diseases , 9 with malignancies , and 7 with non-infectious inflammatory diseases .By FDG PET scan alone , the rates of true positive , false positive , false negative, and true negative were 52.9%, 27.5%, 17.6%, and 2.0%, respectively.By FDG PET/CT scan, the rates of true positive, false positive, false negative, and true negative were 70.6%, 27.5%, 2.0%, and 0, respectively.18F-PET/CT had a sensitivity of 97.3%(36/37), specificity of 0 (0/14), and accuracy of 70.6%(36/51) in FUO, especially a high sensitivity and accuracy of 100%(9/9) in the diagnosis of malignant tumor .Moreover , the maximum standardized uptake value ( SUVmax ) in tumor was significant higher than that in infection (3.7 ±2.7 vs.7.7 ±3.5, P=0.001, t=3.6), which implied that SUVmax might be useful in differential diagnosis in FUO .Conclusion:FDG PET/CT is a valuable imaging tool for the identification and location of the potential lesion in FUO and is helpful for the etiological diagnosis , especially in the diagnosis of malignant lesions .