Department of Nuclear Medicine, Bichat University Hospital, Département Hospitalo-Universitaire FIRE, Assistance Publique-Hôpitaux de Paris, University Paris Diderot-Paris 7, Paris, France Inserm Unité Mixte de Recherche 1148, Bichat University Hospital, Paris, France.
Department of Nuclear Medicine, Bichat University Hospital, Département Hospitalo-Universitaire FIRE, Assistance Publique-Hôpitaux de Paris, University Paris Diderot-Paris 7, Paris, France.
J Nucl Med. 2014 Dec;55(12):1980-5. doi: 10.2967/jnumed.114.141895. Epub 2014 Nov 13.
Echocardiography plays a key role in the diagnosis of infective endocarditis (IE) but can be inconclusive in patients in whom prosthetic valve endocarditis (PVE) is suspected. The incremental diagnostic value of (18)F-FDG PET and radiolabeled leukocyte scintigraphy in IE patients has already been reported. The aim of this study was to compare the respective performance of (18)F-FDG PET and leukocyte scintigraphy for the diagnosis of PVE in 39 patients.
(18)F-FDG PET and leukocyte scintigraphy were performed on 39 consecutive patients admitted because of clinically suspected PVE and inconclusive echocardiography results. The results of (18)F-FDG PET and leukocyte scintigraphy were analyzed separately and retrospectively by experienced physicians masked to the results of the other imaging technique and to patient outcome. The final Duke-Li IE classification was made after a 3-mo follow-up.
Of the 39 patients, 14 were classified as having definite IE, 4 as having possible IE, and 21 as not having IE. The average interval between (18)F-FDG PET and leukocyte scintigraphy was 7 ± 7 d. Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were 93%, 71%, 68%, 94%, and 80%, respectively, for (18)F-FDG PET and 64%, 100%, 100%, 81%, and 86%, respectively, for leukocyte scintigraphy. Discrepancies between the results of (18)F-FDG PET and leukocyte scintigraphy occurred in 12 patients (31%). In patients with definite IE, 5 had true-positive (18)F-FDG PET results but false-negative leukocyte scintigraphy results. Of these 5 patients, 3 had nonpyogenic microorganism IE (Coxiella or Candida). Of patients for whom endocarditis had been excluded, 6 had true-negative leukocyte scintigraphy results but false-positive (18)F-FDG PET results. These 6 patients had been imaged in the first 2 mo after the last cardiac surgery. The last patient with a discrepancy between (18)F-FDG PET and leukocyte scintigraphy was classified as having possible endocarditis and had positive (18)F-FDG PET results and negative leukocyte scintigraphy results.
(18)F-FDG PET offers high sensitivity for the detection of active infection in patients with suspected PVE and inconclusive echocardiography results. Leukocyte scintigraphy offers a higher specificity, however, than (18)F-FDG PET for diagnosis of IE and should be considered in cases of inconclusive (18)F-FDG PET findings or in the first 2 mo after cardiac surgery.
比较（18）F-FDG PET 和核素白细胞扫描在 39 例疑似人工瓣心内膜炎（PVE）患者中的诊断效能。
对 39 例因疑似 PVE 且超声心动图结果不确定而入院的患者进行（18）F-FDG PET 和核素白细胞扫描。（18）F-FDG PET 和核素白细胞扫描的结果由经验丰富的医生进行分析，这些医生对其他影像学技术的结果以及患者的结局均不知情。最终的 Duke-Li 心内膜炎分类是在 3 个月的随访后进行的。
39 例患者中，14 例被诊断为明确的心内膜炎，4 例为可能的心内膜炎，21 例为非心内膜炎。（18）F-FDG PET 和核素白细胞扫描的平均间隔时间为 7±7 d。（18）F-FDG PET 的敏感性、特异性、阳性预测值、阴性预测值和准确性分别为 93%、71%、68%、94%和 80%，核素白细胞扫描的分别为 64%、100%、100%、81%和 86%。（18）F-FDG PET 和核素白细胞扫描的结果不一致发生在 12 例患者（31%）中。在明确的心内膜炎患者中，5 例（18）F-FDG PET 结果阳性而核素白细胞扫描结果阴性。这 5 例患者中，有 3 例为非化脓性微生物心内膜炎（Q 热或假丝酵母菌）。在排除心内膜炎的患者中，6 例核素白细胞扫描结果阴性而（18）F-FDG PET 结果阳性。这 6 例患者是在最后一次心脏手术后的 2 个月内进行的影像学检查。最后 1 例（18）F-FDG PET 和核素白细胞扫描结果不一致的患者被归类为可能的心内膜炎，（18）F-FDG PET 结果阳性，核素白细胞扫描结果阴性。
（18）F-FDG PET 对疑似 PVE 且超声心动图结果不确定的患者中活动性感染的检测具有较高的敏感性。然而，核素白细胞扫描对 IE 的诊断具有比（18）F-FDG PET 更高的特异性，因此，对于（18）F-FDG PET 结果不确定或在心脏手术后 2 个月内，应考虑核素白细胞扫描。
