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Background: [ 18 F]FDG-PET/CT is one of the most important diagnostic techniques in the work-up of patients with fever of unknown origin (FUO)/inflammation of unknown origin (IUO). Little is known on how to optimize the diagnostic value of [ 18 F]FDG-PET/CT in patients with FUO/IUO., Methods: Retrospective study in all patients who underwent [ 18 F]FDG-PET/CT during the work-up of FUO/IUO in a tertiary expert center between 2005 and 2014. Data were extracted from medical records., Results: One hundred and four patients were identified, of whom 68 had a final diagnosis (65.4%). Mainly infections (30.8%) and non-infectious inflammatory diseases (30.8%). [ 18 F]FDG-PET/CT contributed to the final diagnosis in 47 of the 68 patients (69.1%). In 21 patients [ 18 F]FDG-PET/CT did not help making a diagnosis. In ten of these patients [ 18 F]FDG-PET/CT was performed while body temperature, CRP and ESR were normal or unknown. Sixteen of 104 patients underwent repeated [ 18 F]FDG-PET/CT. The second scan contributed to the final diagnosis in five of these patients. In two of these patients, the first scan retrospectively was truly non-contributory. In both patients the first [ 18 F]FDG-PET/CT was made while CRP/ESR was low and fever was not present or not measured. A third or fourth scan never contributed to the final diagnosis when the second one did not., Conclusions: [ 18 F]FDG-PET/CT contributed to the final diagnosis in 45.2% of patients, but never contributed when both inflammatory parameters and body temperature were normal. Repeating [ 18 F]FDG-PET/CT should only be done in patients with a non-contributory [ 18 F]FDG-PET/CT when new symptoms or signs appear, or when the first scan was made in absence of fever or elevated inflammatory parameters.

FDG-PET/CT has proven its clinical value and cost-effectiveness in diagnosing metastatic infections in patients with Gram-positive bacteremia. In identification of metastatic foci, FDG-PET/CT is useful as a screening method when localizing symptoms are absent because it provides whole-body coverage. FDG-PET/CT detects early metabolic activity rather than the late anatomical changes as visualized by computed tomography and magnetic resonance imaging. FDG-PET/CT allows more precise localization of infection within a shorter time span between injection and diagnosis as compared to conventional nuclear imaging. This review focuses on the clinical application of imaging of metastatic infectious diseases, with an emphasis on FDG-PET/CT putting it in perspective with other imaging modalities.

Purpose: The purpose of this study was to evaluate the diagnostic value of 18 F-fluorodeoxyglucose (FDG) positron emission tomography and computed tomography (PET/CT scan) and magnetic resonance imaging (MRI) in diagnosing spondylodiscitis and its complications, such as epidural and paraspinal abscesses., Methods: From January 2006 to August 2013 patients with a clinical suspicion of spondylodiscitis, with an infection, or with fever of unknown origin were retrospectively included if 18 F-FDG-PET/CT and MRI of the spine were performed within a 2-week time span. Imaging results were compared to the final clinical diagnosis and follow-up data were collected., Results: Sixty-eight patients were included of whom 49 patients were diagnosed with spondylodiscitis. MRI showed an overall sensitivity of 67 % and specificity of 84 %. Diagnostic accuracy was 58 %, when MRI was performed within 2 weeks after the start of symptoms and improved to 82 %, when performed more than 2 weeks after onset of symptoms. 18 F-FDG-PET/CT showed a sensitivity of 96 % and a specificity of 95 %, with no relation to the interval between the scan and the start of symptoms., Conclusions: As compared to MRI, 18 F-FDG-PET/CT has superior diagnostic value for detecting early spondylodiscitis. After 2 weeks both techniques perform similarly., Competing Interests: Compliance with ethical standards Ethical standards According to the Dutch law, this study was exempt from approval by an ethics committee, because of the retrospective character of this study and the anonymous storage of data. Conflict of interest The authors declare that they have no conflict of interest.

Purpose of the Report: Metastatic infection is a severe complication of bacteremia with high morbidity and mortality. The aim of this study was to investigate the diagnostic value of 18F-FDG PET combined with CT (FDG PET/CT) in children suspected of having metastatic infection., Methods: The results of FDG PET/CT scans performed in children because of suspected metastatic infection from September 2003 to June 2013 were analyzed retrospectively. The results were compared with the final clinical diagnosis., Results: FDG PET/CT was performed in 13 children with suspected metastatic infection. Of the total number of FDG PET/CT scans, 38% were clinically helpful. Positive predictive value of FDG PET/CT was 71%, and negative predictive value was 100%., Conclusions: FDG PET/CT appears to be a valuable diagnostic technique in children with suspected metastatic infection. Prospective studies of FDG PET/CT as part of a structured diagnostic protocol are needed to assess the exact additional diagnostic value.

Invasive group A streptococcal infection is a severe disease with high mortality. Invasive group A streptococcal infection may arise after pelvic inflammatory disease. Pelvic inflammatory disease in postmenopausal women is rare. Here, we report a unique case of a postmenopausal woman with fatal invasive group A streptococcal infection due to pelvic inflammatory disease and an extraordinary course of diagnosis.

Fever of unknown origin (FUO) is commonly defined as fever higher than 38.3°C on several occasions during at least 3 weeks with uncertain diagnosis after a number of obligatory tests. FUO remains a clinical challenge as no diagnosis is reached in up to 50% of cases. In general, infection accounts for one-fourth of cases of FUO, followed by neoplasm and noninfectious inflammatory diseases. FDG-PET is a sensitive diagnostic technique for the evaluation of FUO. Especially integrated imaging combining PET and CT facilitates anatomical localization of focally increased FDG uptake, thereby guiding further diagnostic tests to achieve a final diagnosis. FDG-PET/CT appears to be a more sensitive diagnostic tool in FUO than stand-alone FDG-PET, because of the precise anatomical localization of small lesions and better differentiation between physiological and pathologic metabolic foci. With FDG-PET/CT becoming widely available, FDG-PET/CT should be a routine procedure in the workup of FUO., (Copyright © 2013 Elsevier Inc. All rights reserved.)

Purpose: Early detection of infectious endocarditis is challenging. For diagnosing infectious endocarditis, the revised Duke criteria are the gold standard. Evidence of endocardial involvement on echocardiography is a major criterion, but sensitivity and specificity of echocardiography are not optimal. Here we investigated the utility of (18)F-fluorodeoxyglucose (FDG) positron emission tomography and computed tomography (PET/CT) to diagnose infectious endocarditis in patients with gram-positive bacteraemia., Methods: Seventy-two patients with gram-positive bacteraemia were prospectively included. Patients with a positive blood culture growing Staphylococcus aureus, Streptococcus species or Enterococcus species were eligible when a risk factor for developing metastatic infectious foci was present. Infectious endocarditis was defined according to the revised Duke criteria. All patients underwent (18)F-FDG PET/CT and echocardiography. (18)F-FDG uptake in or around the heart valves was evaluated independently by two nuclear medicine physicians., Results: Sensitivity for diagnosing infectious endocarditis with (18)F-FDG PET/CT was 39% and specificity was 93%. The positive predictive value was 64% and negative predictive value was 82%. The mortality rate in patients without infectious endocarditis and without increased (18)F-FDG uptake in or around the heart valves was 18%, and in patients without infectious endocarditis but with high (18)F-FDG uptake in or around the heart valves the mortality rate was 50% (p = 0.181)., Conclusion: (18)F-FDG PET/CT is currently not sufficiently adequate for the diagnosis of infectious endocarditis because of its low sensitivity. Improvements such as patient preparation with low carbohydrate-fat allowed diet and technical advances in the newest PET/CT scanners may increase sensitivity in future studies.

Objective: In assisted reproductive techniques it is important to find a balance between high pregnancy and acceptable multiple pregnancy rates. In IVF treatment, stimulation with highly purified human menopausal gonadotropin (hMG) results in comparable or even higher pregnancy rates at lower oocyte yields compared to recombinant FSH. Since highly purified hMG contains LH activity, a number of the advantages of highly purified hMG may be attributed to this LH activity. In IUI treatment the effectiveness of highly purified hMG has been barely investigated. The aim of this study was to examine the effectiveness of highly purified hMG in IUI patients treated with a mild stimulation protocol., Study Design: In this retrospective study 378 patients were included, receiving 1400 IUI cycles between January 2006 and December 2007. Patients were first treated with three subsequent natural cycles without controlled ovarian hyperstimulation, followed by three subsequent cycles stimulated with highly purified hMG. Primary outcomes were ongoing pregnancy rate and multifollicular growth. Secondary outcomes were multiple pregnancy and miscarriage rates. Primary and secondary outcomes were expressed in percentages with associated 95% confidence intervals (95%CI). Differences in the outcomes between natural and stimulated cycles were calculated using χ(2) tests. Statistical differences were determined at P < 0.05., Results: Ongoing pregnancy rates increased from 6% (95%CI 4.7-7.7) per natural cycle to 7.4% (95%CI 5.2-10.3) per highly purified hMG stimulated cycle (p = 0.34). The highest ongoing pregnancy rate was observed in the fifth treatment cycle (10.8% (95%CI 6.6-17)), which is significantly higher than the ongoing pregnancy rate in the unstimulated group (p = 0.03). In the highly purified hMG group three (9.7% (95%CI 3.3-24.9)) of the ongoing pregnancies were twin pregnancies, in the unstimulated group there was one (1.7% (95%CI 0.3-9.0)) twin pregnancy (p = 0.08)., Conclusion: Our results indicate that mild stimulation with highly purified hMG in IUI treatment results in an acceptable balance between ongoing and multiple pregnancy rates. Future prospective trials should compare mild stimulation protocols to protocols directly starting with controlled ovarian hyperstimulation. Furthermore, these trials should compare other types and dosages of gonadotropins., (Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.)