Keidar Zohar, Gurman-Balbir Alexandra, Gaitini Diana, Israel Ora
Department of Nuclear Medicine, Rambam Health Care Campus, Haifa, Israel.
J Nucl Med. 2008 Dec;49(12):1980-5. doi: 10.2967/jnumed.108.054692. Epub 2008 Nov 7.
Fever of unknown origin (FUO) is a challenging diagnostic problem. Timely identification and precise localization of the causing process are critical for appropriate patient management. The present prospective study evaluates the role of PET/CT using (18)F-FDG in the investigation of FUO.
A total of 48 consecutive patients (25 men, 23 women; age range, 24-82 y) with FUO underwent (18)F-FDG PET/CT scans. FUO was defined as a fever of more than 38.3 degrees C that lasted for more than 3 wk and failure to reach diagnosis after more than 1 wk of inpatient investigation. The performance of PET/CT for identifying the etiology of FUO was assessed. Final diagnosis was based on histopathology, microbiologic assays, or clinical and imaging follow-up.
PET/CT detected suggestive foci of increased (18)F-FDG uptake in 27 patients. In 22 of these 27 positive studies (81%), PET/CT identified the underlying disease and diagnosed infection in 9 patients, an inflammatory process in 10 patients, and malignancy in 3 patients. (18)F-FDG PET/CT was negative in 21 patients. All these patients were diagnosed as having systemic nonfocal infection or drug-induced fever or showed spontaneous resolution of the febrile state with no further evidence of a localized inflammatory, infectious, or malignant process for a clinical follow-up period of 12-36 mo.
(18)F-FDG PET/CT identified the underlying cause of the fever in 46% of the present study population and contributed to the diagnosis or exclusion of a focal pathologic etiology of the febrile state in 90% of patients. (18)F-FDG PET/CT has a high negative predictive value (100%) for assessment of FUO. If confirmed by further studies, (18)F-FDG PET/CT may be used in the future as an initial noninvasive diagnostic modality for assessment of this group of patients.
不明原因发热（FUO）是一个具有挑战性的诊断难题。及时识别并精确确定病因对于患者的恰当管理至关重要。本前瞻性研究评估了使用（18）F-FDG的PET/CT在不明原因发热调查中的作用。
共有48例连续的不明原因发热患者（25例男性，23例女性；年龄范围24 - 82岁）接受了（18）F-FDG PET/CT扫描。不明原因发热定义为体温超过38.3摄氏度，持续超过3周，且经过1周以上的住院检查仍未确诊。评估了PET/CT识别不明原因发热病因的性能。最终诊断基于组织病理学、微生物学检测或临床及影像学随访。
PET/CT在27例患者中检测到（18）F-FDG摄取增加的提示性病灶。在这27项阳性研究中的22例（81%）中，PET/CT确定了潜在疾病，其中9例诊断为感染，10例为炎症过程，3例为恶性肿瘤。21例患者的（18）F-FDG PET/CT为阴性。所有这些患者被诊断为全身性非局灶性感染或药物性发热，或者在12 - 36个月的临床随访期内发热状态自发缓解，且无进一步的局部炎症、感染或恶性病变证据。
在本研究人群中，（18）F-FDG PET/CT在46%的患者中确定了发热的潜在原因，并在90%的患者中有助于诊断或排除发热状态的局灶性病理病因。（18）F-FDG PET/CT在评估不明原因发热方面具有较高的阴性预测价值（100%）。如果进一步研究得到证实，（18）F-FDG PET/CT未来可能作为评估这类患者的初始非侵入性诊断方法。
