Rheumatic fever: a forgotten but still existing cause of fever of unknown origin detected on FDG PET/CT.

We present a case of heterogeneous and strongly increased myocardial and valvular 18F-FDG uptake on 18F-FDG PET/CT in an HIV-positive patient with productive cough, fever, weight loss, and progressive dyspnea for 6 months. Contrast-enhanced CT did not reveal the cause of fever, but hyperechogenic valvular lesions on echocardiography in combination with PET/CT findings are suggestive of endocarditis/myocarditis. Postmortem histology 3 weeks after PET/CT showed Aschoff bodies with Anitschkow cells, pathognomonic for rheumatic carditis.

Effect of AIDS on women who have sex-determined health issues.

Worldwide, women account for a growing percentage of human immunodeficiency virus (HIV)-infected patients and more than half of all HIV infections. For many years, morphologic imaging methods were the main approaches employed to investigate HIV and its complications. However, during the past decade, advancements in PET and SPECT imaging technologies opened new possibilities for improved understanding of the pathophysiological processes in HIV.

Antimicrobial peptides: their role as infection-selective tracers for molecular imaging.

Antimicrobial peptides (AMPs) are a heterogeneous class of compounds found in a variety of organisms including humans and, so far, hundreds of these structures have been isolated and characterised. They can be described as natural microbicide, selectively cytotoxic to bacteria, whilst showing minimal cytotoxicity towards the mammalian cells of the host organism. They act by their relatively strong electrostatic attraction to the negatively charged bacterial cells and a relatively weak interaction to the eukaryote host cells.

CA 15.3 measurements for separating FDG PET/CT positive from negative findings in breast carcinoma recurrence. Factors influencing the area under the ROC curve.

Unlabelled: In breast cancer CA 15.3 is considered the tumour marker of choice. CA 15.

Targeting monocytes and macrophages by means of SPECT and PET.

Monocytes have been isolated from patient's blood and directly radiolabelled in vitro using a variety of radiopharmaceuticals such as 99mTc-HMPAO, 111In-oxine, 99mTc-colloids and 18F-FDG. Overall, the best labeling results were obtained using 99mTc-HMPAO. The wide availability of 99mTc and of the ligand HMPAO in kit-formulation makes it the most versatile procedure for imaging localized inflammation using in-vitro labeling.

Role of nuclear medicine in neuroHIV: PET, SPECT, and beyond.

HIV-associated neurocognitive disorders (HAND) remain among the most common clinical disorders encountered in people infected with HIV despite widespread use of antiretroviral therapy. There is an enormous need for further evaluation and early diagnosis of HAND. The variety of PET agents such as FDG, C-PiB and [C]-R-PK11195 as well as SPECT agents Tc-HMPAO, I-FP-CIT and I-IBZM have been investigated for the diagnosis of HAND, for distinguishing between demented and nondemented HIV patients, for differentiation between HAND and nonHIV related dementia, as well as for assessing the influence of coinfection with the other viral pathogens on the brain functionality.

Evaluating the possible role of 68Ga-citrate PET/CT in the characterization of indeterminate lung lesions.

Unlabelled: We sought to determine whether PET/CT imaging with (68)Ga-citrate could be of value in distinguishing benign from malignant lung pathology in a setting with a high prevalence of granulomatous diseases.

Methods: Thirty-six consecutive patients with indeterminate lung lesions prospectively underwent dual time point (60 and 120 min) (68)Ga-citrate PET/CT study prior to lung biopsy. Qualitative and semi-quantitative measures of tracer uptake in the lung lesions (SUVmax) were compared to the histopathology in order to establish an imaging pattern to distinguish benign from malignant lesions.

68Ga-citrate PET/CT in tuberculosis: a pilot study.

Background: Tuberculosis remains an important cause of morbidity and mortality worldwide, the diagnosis, staging and treatment response evaluation of which remains sub-optimal. We evaluated PET/CT imaging with a novel tracer, 68Ga-citrate, in this setting.

Methods: Thirteen patients with tuberculosis underwent PET/CT imaging with 68Ga-citrate.

Peptide synthesis, characterization and ⁶⁸Ga-radiolabeling of NOTA-conjugated ubiquicidin fragments for prospective infection imaging with PET/CT.

Introduction: Human antimicrobial peptides are of interest for the development of positron emission tomography (PET) tracers as they exhibit desirable characteristics that make them good candidates for targeting vectors. Due to their natural role in the innate immune system they selectively bind to pathogenic bacteria and yeast, whilst remaining minimally immunogenic and cytotoxic to humans. Research into ubiquicidin (UBI)-based tracers has focused on (99m)Tc as a radionuclide, however, the use of bi-functional chelators such as 1,4,7-triazacyclononane-1,4,7-triacetic acid (NOTA), in combination with ⁶⁸Ga as a radionuclide, allows for a simple radiolabeling procedure which is preferable in a clinical setting using PET/CT.

Advances in imaging of tuberculosis: the role of ¹⁸F-FDG PET and PET/CT.

Purpose Of Review: To review the main applications, advantages and limitations of ¹⁸F-FDG PET and PET/computed tomography (CT), and some other tracers in imaging of tuberculosis (TB).

Recent Findings: In pulmonary TB, granulomas typically demonstrate increased ¹⁸F-FDG uptake, and areas of active TB can be differentiated from old or inactive disease by dual time point imaging. However, standardized uptake value measurements are high in both TB and malignant lesions, with significant overlap that limits their usefulness.

Preclinical evaluation of 68Ga-labeled 1,4,7-triazacyclononane-1,4,7-triacetic acid-ubiquicidin as a radioligand for PET infection imaging.

Unlabelled: Antimicrobial peptides such as ubiquicidin (UBI) are believed to differentiate between mammalian and bacterial or fungal cells. (99m)Tc-UBI29-41 was previously tested for detecting infection in humans using SPECT. For the present study, the UBI fragment UBI29-41 (TGRAKRRMQYNRR) was conjugated to 1,4,7-triazacyclononane-triacetic acid (NOTA), radiolabeled with (68)Ga, and investigated in a rabbit infection model.

Production of high specific activity (195m) Pt-cisplatinum at South African Nuclear Energy Corporation for Phase 0 clinical trials in healthy individual subjects.

Platinum agents continue to be the main chemotherapeutic agents used in the first-line and second-line treatments of cancer patients. It is important to fully understand the biological profile of these compounds in order to optimize the dose given to each patient. In a joint project with the Australian Nuclear Science and Technology Organisation and the Nuclear Medicine Department at Steve Biko Academic Hospital, South African Nuclear Energy Corporation synthesized and supplied (195m) Pt-cisplatinum (commonly referred to as cisplatin) for a clinical pilot study on healthy volunteers.

A modified technique for efficient radiolabeling of 68Ga-citrate from a SnO2-based 68Ge/68Ga generator for better infection imaging.

Our aim was to develop a practical method to prepare 68Ga-citrate using a SnO2-based 68Ge/68Ga generator and evaluate its use in infection imaging. 68Ga-citrate synthesis was performed in a straight forward, quantitative, one-step-aseptic procedure; an amended labeling method was applied using ACD-A buffered citrate as a precursor. Study participants were imaged on a Siemens Biograph 40 PET/CT scanner 60 min post intravenous injection.

Development and prospects of dedicated tracers for the molecular imaging of bacterial infections.

Bacterial infections have always been, and still are, a major global healthcare problem. For accurate treatment it is of upmost importance that the location(s), severity, type of bacteria, and therapeutic response can be accurately staged. Similar to the recent successes in oncology, tracers specific for molecular imaging of the disease may help advance patient management.

Association of hemodynamic response during dipyridamole stress testing with 99mTc-MIBI SPET myocardial perfusion image findings.

The aim of this study was to assess whether there is an association between changes in the heart rate and blood pressure after dipyridamole stress and abnormal scan findings detected with gated technetium-99m methoxy isobutylisonitrile (99mTc-MIBI) myocardial perfusion imaging (MPI). A total of 200 consecutive patients with known or suspected coronary artery disease underwent MPI using a 2 days stress/rest protocol. Heart rate (HR), blood pressure and electrocardiogram were monitored during the stress study.

Biodistribution and dosimetry of 195mPt-cisplatin in normal volunteers. Imaging agent for single photon emission computed tomography.

Unlabelled: 195mPt-cisplatin is regarded as a promising imaging agent for optimizing dosage in patients receiving cisplatin chemotherapy.

Methods: We investigated the whole-body distribution and radiation dosimetry of 195mPt-cisplatin in humans. Whole-body scans were obtained up to 144 h after intravenous injection of 112.

Radiolabelled probes targeting tumor hypoxia for personalized medicine.

Hypoxia is a characteristic feature of many solid tumors which has been described in a wide range of tumor types. Its presence impairs the effectiveness of common anti-cancer therapies and accordingly, tumor hypoxia has been associated with an aggressive tumor phenotype, poor response to radio- and chemotherapy, and worse prognosis. In order to predict outcome and identify patients with a worse prognosis and/or patients that would benefit from appropriate treatments, in vivo measurement of tumor hypoxia is required.

FDG-PET imaging in HIV infection and tuberculosis.

The intersection and syndemic interaction between the human immunodeficiency virus (HIV) and tuberculosis (TB) epidemics have global prevalence with devastating morbidity and massive mortality. Using FDG-PET imaging it was shown that in HIV-infected individuals, involvement of the head and neck precedes that of the chest and of the abdomen. The sequence of lymph node involvement observed suggests the existence of a diffusible activation mediator that may be targeted via therapeutic intervention strategies.

Gallium-68: a systematic review of its nononcological applications.

The increased availability of PET facilities worldwide has sparked renewed interest in the use of generator-produced tracers such as gallium-68 (Ga). Imaging with Ga provides exciting opportunities in terms of new ligand-labelling possibilities and the exploration of novel clinical applications. The aim of the study was to summarize and appraise what has been published on the clinical applications of Ga outside oncology practice.

Combined 18F-fluoride and 18F-FDG PET/CT scanning for evaluation of malignancy: results of an international multicenter trial.

Unlabelled: (18)F-FDG PET/CT is used in a variety of cancers, but because of variable rates of glucose metabolism, not all cancers are reliably identified. (18)F(-) PET/CT allows for the acquisition of highly sensitive and specific images of the skeleton. We prospectively evaluated combined (18)F(-)/(18)F-FDG as a single PET/CT examination for evaluation of cancer patients and compared it with separate (18)F(-) PET/CT and (18)F-FDG PET/CT scans.

Prevalence and pattern of brown adipose tissue distribution of 18F-FDG in patients undergoing PET-CT in a subtropical climatic zone.

Background: The uptake of F-FDG in brown adipose tissue (BAT) may have important implications in understanding the pathophysiology of BAT and obesity. Because of the thermal implications of BAT uptake of F-FDG, this study aimed to contribute to existing knowledge by assessing patients scanned in a subtropical environment with particular reference to ethnicity.

Patients And Methods: A retrospective study was carried out to determine the prevalence and pattern of BAT uptake in patients undergoing F-FDG PET-CT imaging in a PET facility located in a subtropical climatic zone.

Predictive and prognostic value of metabolic tumour volume and total lesion glycolysis in solid tumours.

Data available in patients suffering from squamous cell carcinoma of the head and neck, lung carcinoma, oesophageal carcinoma and gynaecological malignancies suggest that metabolic tumour volume and to a lesser extent total lesion glycolysis have the potential to become valuable in the imaging of human solid tumours as prognostic biomarkers for short- to intermediate-term survival outcomes, adding value to clinical staging, for assessment of response to treatment with neoadjuvant and concurrent chemotherapy, and for treatment optimization; for example, based on early treatment response assessment using changes in metabolic tumour volume over time, it might be possible to select patients who require a more aggressive treatment to improve their outcome. Prospective studies enrolling consecutive patients, adopting standardized protocols for FDG PET acquisition and processing, adjusting for potential confounders in the analysis (tumour size and origin) and determining the optimal methodology for determination of these novel markers are mandatory.

Blood-brain barrier integrity in a zolpidem-responder patient.

A 27-year-old neurologically disabled but fully conscious male zolpidem-responder patient was investigated for blood brain barrier (BBB) dysfunction 5 years after a traumatic brain injury. A baseline single-photon emission computed tomography (SPECT) technetium-99m-labelled hexamethylpropylene amine oxime (99mTcHMPAO) brain scan was performed and the patient was administered 10 mg zolpidem daily. The patient was rescanned 2 weeks later when 99mTcHMPAO was injected 1 hour after zolpidem application.