Dysregulated innate and adaptive immune responses discriminate disease severity in COVID-19

The clinical spectrum of COVID-19 varies and the differences in host response characterizing this variation have not been fully elucidated. COVID-19 disease severity correlates with an excessive pro-inflammatory immune response and profound lymphopenia. Inflammatory responses according to disease severity were explored by plasma cytokine measurements and proteomics analysis in 147 COVID-19 patients. Furthermore, peripheral blood mononuclear cell cytokine production assays and whole blood flow cytometry were performed. Results confirm a hyperinflammatory innate immune state, while highlighting hepatocyte growth factor and stem cell factor as potential biomarkers for disease severity. Clustering analysis reveals no specific inflammatory endotypes in COVID-19 patients. Functional assays reveal abrogated adaptive cytokine production (interferon-gamma, interleukin-17 and interleukin-22) and prominent T cell exhaustion in critically ill patients, whereas innate immune responses were intact or hyperresponsive. Collectively, this extensive analysis provides a comprehensive insight into the pathobiology of severe to critical COVID-19 and highlight potential biomarkers of disease severity

18F-FDG PET/CT in Detecting Metastatic Infection in Children

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 valu

The diagnostic value of 18F–FDG-PET/CT and MRI in suspected vertebral osteomyelitis – a prospective study

Purpose: The aim of this study was to determine the diagnostic value of 18F–fluorodeoxyglucose (FDG) positron emission tomography and computed tomography (PET/CT) and magnetic resonance imaging (MRI) in diagnosing vertebral osteomyelitis. Methods: From November 2015 until December 2016, 32 patients with suspected vertebral osteomyelitis were prospectively included. All patients underwent both 18F–FDG-PET/CT and MRI within 48 h. All images were independently reevaluated by two radiologists and two nuclear medicine physicians who were blinded to each others’ image interpretation. 18F–FDG-PET/CT and MRI were compared to the clinical diagnosis according to international guidelines. Results: For 18F–FDG-PET/CT, sensitivity, specificity, PPV, and NPV in diagnosing vertebral osteomyelitis were 100%, 83.3%, 90.9%, and 100%, respectively. For MRI, sensitivity, specificity, PPV, and NPV were 100%, 91.7%, 95.2%, and 100%, respectively. MRI detected more epidural/spinal abscesses. An important advantage of 18F–FDG-PET/CT is the detection of metastatic infection (16 patients, 50.0%). Conclusion: 18F–FDG-PET/CT and MRI are both necessary techniques in diagnosing vertebral osteomyelitis. An important advantage of 18F–FDG-PET/CT is the visualization of metastatic infection, especially in patients with bacteremia. MRI is more sensitive in detection of small epidural abscesses

The value of 18F-FDG PET/CT in diagnosis and during follow-up in 273 patients with chronic Q fever

In 1%–5% of all acute Q fever infections, chronic Q fever develops, mostly manifesting as endocarditis, infected aneurysms, or infected vascular prostheses. In this study, we investigated the diagnostic value of 18F-FDG PET/CT in chronic Q fever at diagnosis and during follow-up. Methods: All adult Dutch patients suspected of chronic Q fever who were diagnosed since 2007 were retrospectively included until March 2015, when at least one 18F-FDG PET/CT scan was obtained. Clinical data and results from 18F-FDG PET/CT at diagnosis and during follow-up were collected. 18F-FDG PET/CT scans were prospectively reevaluated by 3 nuclear medicine physicians using a structured scoring system. Results: In total, 273 patients with possible, probable, or proven chronic Q fever were included. Of all 18F-FDG PET/CT scans performed at diagnosis, 13.5% led to a change in diagnosis. Q fever–related mortality rate in patients with and without vascular infection based on 18F-FDG PET/CT was 23.8% and 2.1%, respectively (P 5 0.001). When 18F-FDG PET/CT was added as a major criterion to the modified Duke criteria, 17 patients (1.9-fold increase) had definite endocarditis. At diagnosis, 19.6% of 18F-FDG PET/CT scans led to treatment modification. During follow-up, 57.3% of 18F-FDG PET/CT scans resulted in treatment modification. Conclusion: 18F-FDG PET/CT is a valuable technique in diagnosis of chronic Q fever and during follow-up, often leading to a change in diagnosis or treatment modification and providing important prognostic information on patient survival

The diagnostic value of 18F–FDG-PET/CT and MRI in suspected vertebral osteomyelitis – a prospective study

Purpose: The aim of this study was to determine the diagnostic value of 18F–fluorodeoxyglucose (FDG) positron emission tomography and computed tomography (PET/CT) and magnetic resonance imaging (MRI) in diagnosing vertebral osteomyelitis. Methods: From November 2015 until December 2016, 32 patients with suspected vertebral osteomyelitis were prospectively included. All patients underwent both 18F–FDG-PET/CT and MRI within 48 h. All images were independently reevaluated by two radiologists and two nuclear medicine physicians who were blinded to each others’ image interpretation. 18F–FDG-PET/CT and MRI were compared to the clinical diagnosis according to international guidelines. Results: For 18F–FDG-PET/CT, sensitivity, specificity, PPV, and NPV in diagnosing vertebral osteomyelitis were 100%, 83.3%, 90.9%, and 100%, respectively. For MRI, sensitivity, specificity, PPV, and NPV were 100%, 91.7%, 95.2%, and 100%, respectively. MRI detected more epidural/spinal abscesses. An important advantage of 18F–FDG-PET/CT is the detection of metastatic infection (16 patients, 50.0%). Conclusion: 18F–FDG-PET/CT and MRI are both necessary techniques in diagnosing vertebral osteomyelitis. An important advantage of 18F–FDG-PET/CT is the visualization of metastatic infection, especially in patients with bacteremia. MRI is more sensitive in detection of small epidural abscesses