Radiolabelled WBCs against [18F]FDG PET/CT for imaging infections: the eternal battle

DFIs and VGEIs represent two difficult scenarios from a diagnostic point of view and the prompt identification of the infection benefit from a multidisciplinary and multimodal approach in which NM plays a crucial role. As far as DFIs is concerned, a plethora of radiological and NM modalities are available and can be used and combined for the diagnosis, but at the moment no definite diagnostic flowchart exists (Chapter 2). In Chapter 3, MRI, 99mTc-HMPAO WBC scintigraphy and [18F]FDG PET/CT showed a comparable sensitivity in detecting pedal OM. In Chapter 4, we compared MRI, 99mTc-HMPAO WBC scintigraphy and [18F]FDG PET/CT in detecting OM, STIs and Charcot in a large population of diabetic patients.VGEI is another condition in which standardized diagnostic algorithms and a unanimous consensus on the most appropriate imaging modality are still needed. CTA, WBC scintigraphy and [18F]FDG PET/CT play a complementary role being CTA always the first-choice imaging modality (Chapter 5). From our retrospective comparative study on CTA, radiolabelled WBCs and [18F]FDG PET/CT (Chapters 6), the addition of a NM examination resulted in a better patient’s management in our population. Recently published EANM guidelines (Chapter 7) fully assessed the role of different imaging modalities in the diagnostic setting of VGEI according to time elapsed from surgery. WBC scintigraphy can be performed at any time from surgery, given its high accuracy in discriminating post-surgical inflammation from an infection. [18F]FDG PET/CT should be performed at least 4 months after surgery, given the possibility of false positive findings due to sterile inflammation

Immunoscintigraphy for therapy decision making and follow-up of biological therapies

With the availability of new biological therapies there is the need of more accurate diagnostic tools to noninvasively assess the presence of their targets. In this scenario nuclear medicine offers many radiopharmaceuticals for SPECT or PET imaging of many pathological conditions. The availability of monoclonal antibodies provides tools to target specific antigens involved in angiogenesis, cell cycle or modulation of the immune systems. The radiolabelling of such therapeutic mAbs is a promising method to evaluate the antigenic status of each cancer lesion or inflamed sites before starting the therapy. It may also allow to perform follow-up of such biological therapies. In the present review we provide an overview of the most studied radiolabelled antibodies for therapy decision making and follow-up of patients affected by cancer and other pathological conditions

Diabetic Foot Infections:The Diagnostic Challenges

Diabetic foot infections (DFIs) are severe complications of long-standing diabetes, and they represent a diagnostic challenge, since the differentiation between osteomyelitis (OM), soft tissue infection (STI), and Charcot's osteoarthropathy is very difficult to achieve. Nevertheless, such differential diagnosis is mandatory in order to plan the most appropriate treatment for the patient. The isolation of the pathogen from bone or soft tissues is still the gold standard for diagnosis; however, it would be desirable to have a non-invasive test that is able to detect, localize, and evaluate the extent of the infection with high accuracy. A multidisciplinary approach is the key for the correct management of diabetic patients dealing with infective complications, but at the moment, no definite diagnostic flow charts still exist. This review aims at providing an overview on multimodality imaging for the diagnosis of DFI and to address evidence-based answers to the clinicians when they appeal to radiologists or nuclear medicine (NM) physicians for studying their patients

Immune cell labelling and tracking. implications for adoptive cell transfer therapies

BACKGROUND: The understanding of the role of different immune cell subsets that infiltrate tumors can help researchers in developing new targeted immunotherapies to reactivate or reprogram them against cancer. In addition to conventional drugs, new cell-based therapies, like adoptive cell transfer, proved to be successful in humans. Indeed, after the approval of anti-CD19 CAR-T cell therapy, researchers are trying to extend this approach to other cancer or cell types.MAIN BODY: This review focuses on the different approaches to non-invasively monitor the biodistribution, trafficking and fate of immune therapeutic cells, evaluating their efficacy at preclinical and clinical stages. PubMed and Scopus databases were searched for published articles on the imaging of cell tracking in humans and preclinical models.CONCLUSION: Labelling specific immune cell subtypes with specific radiopharmaceuticals, contrast agents or optical probes can elucidate new biological mechanisms or predict therapeutic outcome of adoptive cell transfer therapies. To date, no technique is considered the gold standard to image immune cells in adoptive cell transfer therapies

Multimodality Imaging in the Diagnostic Work-Up of Endocarditis and Cardiac Implantable Electronic Device (CIED) Infection

Infective endocarditis (IE) is a serious cardiac condition, which includes a wide range of clinical presentations, with varying degrees of severity. The diagnosis is multifactorial and a proper characterization of disease requires the identification of the primary site of infection (usually the cardiac valve) and the search of secondary systemic complications. Early depiction of local complications or distant embolization has a great impact on patient management and prognosis, as it may induce to aggressive antibiotic treatment or, in more advanced cases, cardiac surgery. In this setting, the multimodality imaging has assumed a pivotal role in the clinical decision making and it requires the physician to be aware of the advantages and disadvantages of each imaging technique. Echocardiography is the first imaging test, but it has several limitations. Therefore, the integration with other imaging modalities (computed tomography, magnetic resonance imaging, nuclear imaging) becomes often necessary. Different strategies should be applied depending on whether the infection is suspected or already ascertained, whether located in native or prosthetic valves, in the left or right chambers, or if it involves an implanted cardiac device. In addition, detection of extracardiac IE-related lesions is crucial for a correct management and treatment. The aim of this review is to illustrate strengths and weaknesses of the various methods in the most common clinical scenarios

Handling of Doubtful WBC Scintigraphies in Patients with Suspected Prosthetic Joint Infections

Abstract: Despite the application of EANM recommendations for radiolabelled white-blood-cells (WBC) scintigraphy, some cases still remain doubtful based only on visual analysis. The aim of this study was to investigate the role of semi-quantitative analysis and bone marrow scan (BMS) in solving doubtful cases. We retrospectively evaluated all [99mTc]HMPAO-WBC scintigraphies performed, in the last 7 years, for a suspected monolateral prosthetic joint infection (PJI). In doubtful cases, we used five different thresholds of increase of target-to-background (T/B) ratio, between delayed and late images, as criteria of positivity (5%, 10%, 15%, 20% and 30%). BMS were also analysed and sensitivity, specificity and accuracy of different methods were calculated according to final diagnosis. The sensitivity, specificity and accuracy were, respectively, 77.8%, 43.8% and 53.0% for the cut-off at 5%; 72.2%, 66.7% and 68.2% for the cut-off at 10%; 66.7%, 75.0% and 72.7% for the cut-off at 15%; 66.7%, 85.4% and 80.3% for the cut-off at 20%; 33.3%, 93.8% and 77.3% for the cut-off at 30%. BMS provided a significantly higher diagnostic performance than 5%, 10% and 15% thresholds. Conversely, we did not observe any statistically significant difference between BMS and the cut-off of more than 20%. Therefore, doubtful cases should be analysed semi-quantitatively. An increase in T/B ratio of more than 20% between delayed and late images, should be considered as a criterion of positivity, thus avoiding BMS

Imaging Modalities for the Diagnosis of Vascular Graft Infections:A Consensus Paper amongst Different Specialists

Vascular graft infection (VGI) is a rare but severe complication of vascular surgery that is associated with a bad prognosis and high mortality rate. An accurate and prompt identification of the infection and its extent is crucial for the correct management of the patient. However, standardized diagnostic algorithms and a univocal consensus on the best strategy to reach a diagnosis still do not exist. This review aims to summarize different radiological and Nuclear Medicine (NM) modalities commonly adopted for the imaging of VGI. Moreover, we attempt to provide evidence-based answers to several practical questions raised by clinicians and surgeons when they approach imaging in order to plan the most appropriate radiological or NM examination for their patients

A Clinical Decision Support System based on fuzzy rules and classification algorithms for monitoring the physiological parameters of type-2 diabetic patients

The use of different types of Clinical Decision Support Systems (CDSS) makes possible the improvement of the quality of the therapeutic and diagnostic efficiency in health field. Those systems, properly implemented, are able to simulate human expert clinician reasoning in order to suggest decisions on treatment of patients. In this paper, we exploit fuzzy inference machines to improve the quality of the day-by-day clinical care of type-2 diabetic patients of Anti-Diabetes Centre (CAD) of the Local Health Authority ASL Naples 1 (Naples, Italy). All the designed functionalities were developed thanks to the experience on the field, through different phases (data collection and adjustment, Fuzzy Inference System development and its validation on real cases) executed by an interdisciplinary research team comprising doctors, clinicians and IT engineers. The proposed approach also allows the remote monitoring of patients' clinical conditions and, hence, can help to reduce hospitalizations

Imaging Modalities for the Diagnosis of Vascular Graft Infections: A Consensus Paper amongst Different Specialists

Vascular graft infection (VGI) is a rare but severe complication of vascular surgery that is associated with a bad prognosis and high mortality rate. An accurate and prompt identification of the infection and its extent is crucial for the correct management of the patient. However, standardized diagnostic algorithms and a univocal consensus on the best strategy to reach a diagnosis still do not exist. This review aims to summarize different radiological and Nuclear Medicine (NM) modalities commonly adopted for the imaging of VGI. Moreover, we attempt to provide evidence-based answers to several practical questions raised by clinicians and surgeons when they approach imaging in order to plan the most appropriate radiological or NM examination for their patients

Predictive Role of Serum Thyroglobulin after Surgery and before Radioactive Iodine Therapy in Patients with Thyroid Carcinoma

Introduction: Thyroidectomy followed by radioactive iodine therapy (RAI) is the treatment of choice for differentiated thyroid carcinoma (DTC). Serum thyroglobulin (Tg) measurement has proved to be useful for predicting persistent and/or recurrent disease during follow-up of DTC patients. In our study, we evaluated the risk of disease recurrence in patients with papillary thyroid carcinoma (PTC), who were treated with thyroidectomy and RAI, by measuring serum Tg at different time-points: at least 40 days after surgery, in euthyroidism with TSH < 1.5 and usually 30 days before RAI (Tg−30), on the day of RAI (Tg0), and seven days after RAI (Tg+7). Methods: One hundred and twenty-nine patients with PTC were enrolled in this retrospective study. All patients were treated with 131I for thyroid remnant ablation. Disease relapse (nodal disease or distant disease) during at least 36 months follow-up was evaluated by serum measurements of Tg, TSH, AbTg at different time points and by imaging techniques (neck ultrasonography, 131I-whole body scan (WBS) after Thyrogen® stimulation). Typically, patients were assessed at 3, 6, 12, 18, 24, and 36 months after RAI. We classified patients in five groups: (i) those who developed nodal disease (ND), (ii) those who developed distant disease (DD), (iii) those with biochemical indeterminate response and minimal residual thyroid tissue (R), (iv) those with no evidence of structural or biochemical disease + intermediate ATA risk (NED-I), and (v) those with no evidence of structural or biochemical disease + low ATA risk (NED-L). ROC curves for Tg were generated to find potential discriminating cutoffs of Tg values in all patients’ groups. Results: A total of 15 out of 129 patients (11.63%) developed nodal disease and 5 (3.88%) distant metastases, during the follow-up. We found that Tg−30 (with suppressed TSH) has the same sensitivity and specificity than Tg0 (with stimulated TSH), and it is slightly better than Tg+7, which can be influenced by the size of the residual thyroid tissue. Conclusion: Serum Tg−30 value, measured in euthyroidism 30 days before RAI, is a reliable prognostic factor to predict future nodal or distant disease, thus allowing to plan the most appropriate therapy and follow-up