An untapped potential for imaging of peripheral osteomyelitis in paediatrics using [ ¹⁸ F]FDG PET/CT —the inference from a juvenile porcine model

Abstract Purpose To examine parameters affecting the detection of osteomyelitis (OM) by [18F]FDG PET/CT and to reduce tracer activity in a pig model. Background [18F]FDG PET/CT is recommended for the diagnosis of OM in the axial skeleton of adults. In children, OM has a tendency to become chronic or recurrent, especially in low-income countries. Early diagnosis and initiation of therapy are therefore essential. We have previously demonstrated that [18F]FDG PET/CT is promising in juvenile Staphylococcus aureus (S. aureus) OM of peripheral bones in a pig model, not failing even small lesions. When using imaging in children, radiation exposure should be balanced against fast diagnostics in the individual case. Methods Twenty juvenile pigs were inoculated with S. aureus. One week after inoculation, the pigs were [18F]FDG PET/CT scanned. PET list-mode acquired data of a subgroup were retrospectively processed in order to simulate and examine the image quality obtainable with an injected activity of 132 MBq, 44 MBq, 13.2 MBq, and 4.4 MBq, respectively. Results All lesions were detected by [18F]FDG PET and CT. Some lesions were very small (0.01 cm3), and others were larger (4.18 cm3). SUVmax was higher when sequesters (p = 0.023) and fistulas were formed (p < 0.0001). The simulated data demonstrated that it was possible to reduce the activity to 4.4 MBq without compromising image quality in pigs. Conclusions [18F]FDG PET/CT localized even small OM lesions in peripheral bones. It was possible to reduce the injected activity considerably without compromising image quality, impacting the applicability of PET/CT in peripheral OM in children

International travel and the risk of hospitalization with non-typhoidal Salmonella bacteremia. A Danish population-based cohort study, 1999-2008

<p>Abstract</p> <p>Background</p> <p>Information is sparse regarding the association between international travel and hospitalization with non-typhoidal <it>Salmonella </it>bacteremia. The aim of this study was to determine the proportion, risk factors and outcomes of travel-related non-typhoidal <it>Salmonella </it>bacteremia.</p> <p>Methods</p> <p>We conducted a 10-year population-based cohort study of all patients hospitalized with non-typhoidal <it>Salmonella </it>bacteremia in three Danish counties (population 1.6 million). We used denominator data on Danish travellers to assess the risk per 100,000 travellers according to age and travel destination. We used patients contemporaneously diagnosed with travel-related <it>Salmonella </it>gastroenteritis as reference patients to estimate the relative risk of presenting with travel-related bacteremia as compared with gastroenteritis. To evaluate clinical outcomes, we compared patients with travel-related bacteremia and patients with domestically acquired bacteremia in terms of length of hospital stay, number of extraintestinal focal infections and mortality after 30 and 90 days.</p> <p>Results</p> <p>We identified 311 patients hospitalized with non-typhoidal <it>Salmonella </it>bacteremia of whom 76 (24.4%) had a history of international travel. The risk of travel-related bacteremia per traveller was highest in the age groups 15-24 years (0.8/100,000 travellers) and 65 years and above (1.2/100,000 travellers). The sex- and age-adjusted relative risk of presenting with bacteremia was associated with travel to Sub-Saharan Africa (odds ratio 18.4; 95% confidence interval [6.9-49.5]), the Middle East (10.6; [2.1-53.2]) and South East Asia (4.0; [2.2-7.5]). We found high-risk countries in the same three regions when estimating the risk per traveller according to travel destination. Patients hospitalized with travel-related bacteremia had better clinical outcomes than patients with domestically acquired bacteremia, they had a shorter length of hospital stay (8 vs. 11 days), less extraintestinal focal infections (5 vs. 31 patients) and a lower risk of death within both 30 days (relative risk 0.2; [0.1-0.7]) and 90 days (0.3; [0.1-0.7]). A healthy traveller effect was a plausible explanation for the observed differences in outcomes.</p> <p>Conclusions</p> <p>International travel is a notable risk factor for being hospitalized with non-typhoidal <it>Salmonella </it>bacteremia and the risk differs between age groups and travel destinations. Healthy travellers hospitalized with bacteremia are less likely to have poor outcomes than patients with domestically acquired bacteremia.</p

Direct Identification of Major Blood Culture Pathogens, Including Pseudomonas aeruginosa and Escherichia coli, by a Panel of Fluorescence In Situ Hybridization Assays Using Peptide Nucleic Acid Probes

Rapid identification of four major pathogens from 1,231 positive blood cultures by fluorescence in situ hybridization with peptide nucleic acid probes (AdvanDx Inc., Woburn, Mass.) was evaluated. For Escherichia coli, Staphylococcus aureus, and Candida albicans results agreed with conventional identification. The lower sensitivity of the Pseudomonas aeruginosa assay should not compromise the utility of the four assays