The high mortality rates among patients waiting for liver transplantation has motivated the use of 'marginal livers', among which are included livers from deceased donors serologically positive for Chagas disease (CD). The present work describes the outcome of orthotopic liver transplantation in six patients with severe liver disease (Child Pugh C), with livers from donors serologically positive for CD. Transplantations were performed from November 2000 to January 2005, and the patients received prophylactic treatment with benznidazole for 60 days, as a recommended by the Brazilian Consensus in Chagas Disease. The transplantation procedures presented no technical problems, and all the patients were discharged from hospital. Five of them did not present side effects demanding interruption of the prophylactic treatment. Four of the patients were clinically well over 1 year after transplantation (mean follow-up of 42.1 months), with negative serological results for CD. Two patients died, one of them 6 months post surgery of sepsis due to biliary complication and other one due to pulmonary (tuberculosis) complications. They were both serologically negative for CD. These results suggest that liver transplantation from CD donors, followed by benznidazole prophylactic treatment, is an important therapeutic alternative for severe liver disease.

Background The observation that 2-deoxy-2[18F]fluoro-D-glucose-positron emission tomography/magnetic resonance imaging ([18F]F-FDG-PET/MRI) revealed high-grade arterial wall FDG uptake, without arterial wall thickening with contrast-enhancement, in a considerable number of c-TA patients in our previous study, encouraged us to compare patients with both PET and MR angiography (MRA) positives, with those with PET positive but MRA negative. Our aim was to evaluate the relevance of these two imaging modalities together. Methods A three-center cross-sectional study with 17 patients who fulfilled the EULAR/PRINTO/PReS criteria for c-TA and who underwent [18F]F-FDG-PET/MRI was previously performed. Herein we compared patients/vessels with positive PET (arterial wall 18F-FDG uptake higher than liver) and positive MRA (arterial wall thickening with contrast-enhancement)—group 1, with those with positive PET but negative MRA—group 2. Results Median disease duration of 17 c-TA patients was 10.4 years. Nine patients were classified as group 1 and six as group 2. Median of metabolic inflammatory volume (MIV) of all arterial segments was significantly higher in group 1 (2346 vs. 1177 cm3; p = 0.036). Fifty-four (19%) from 284 available arterial segments presented positive findings in vessel wall in one or both images. Positive findings were concordant between PET and MRA in only 13% arterial segments (group 1); most changes (28–59.6%) that were discordant between both images, were positive in PET and negative in MRA (group 2). Conclusion Our study demonstrated that [18F]F-FDG-PET/MRI added information about inflammation in vessel wall of c-TA patients. Prospective multicenter studies are needed in order to get solid data to guide immunosuppressive tapering and withdrawal.

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Objectives To assess whether 18F-fluordeoxiglucose-positron emission tomography/magnetic resonance imaging (18F-FDG-PET/MRI) with angiographic sequences can contribute to detecting vessel wall inflammation in patients with childhood-onset Takayasu’s arteritis (c-TA) under immunosuppressive therapy. Methods Three-centre cross-sectional study was conducted. 18F-FDG-PET/MRI scans were performed in c-TA patients and in oncologic patients, who served as the control group. Clinical and laboratorial characteristics were also analysed. Results Seventeen c-TA patients (65% females) between the ages of 6 and 21 years, mean disease duration of 9.4 years were recruited. Only one patient presented clinical disease activity, and six (35.6%) had increased erythrocyte sedimentation rate (ESR) and/or C-reactive protein (CRP) levels. The most frequent magnetic resonance angiography (MRA) findings were stenosis and thickening, observed in 82.4% and 70.6% of c-TA patients, respectively. 18F-FDG-PET revealed 18F-FDG uptake higher than the liver in at least one arterial segment in 15 (88.2%) patients in a qualitative analysis and median standardized uptake value (SUVmax) of 3.22 (2.76-3.69) in a semi-quantitative analysis. c-TA patients presented significantly higher SUVmax than oncologic patients (p < 0.001). A positive correlation between SUVmax and CRP levels (Rho=0.528; p=0.029) was evidenced. Conclusion A state-of-the-art imaging modality was used in c-TA patients and revealed a strong arterial FDG uptake even in patients in apparent remission. We suppose that this finding may represent a silent activity in the vessel wall; however, we cannot exclude the possibility of arterial remodelling. Importantly, a negative imaging scan may help in immunosuppression withdrawal in daily clinical practice.

IntroductionChildhood-onset Takayasu Arteritis (c-TA) is a rare, large-vessel vasculitis seen in children that could predisposing patients to a high risk of mortality. Exercise has the potential to improve overall health in several diseases, but evidence remains scant in c-TA. The main objective of this study was to investigate the safety and potential therapeutic effects of exercise in c-TA.MethodsThis was a 12-week, multicenter, randomized, controlled trial, to test the effects of a home-based, exercise intervention vs. standard of care in c-TA patients in remission. The primary outcomes were arterial inflammation, assessed by [18F] FDG- PET/MRI and systemic inflammatory markers. Secondary outcomes included, physical activity levels, functionality, body composition, disease-related parameters, and quality of life.ResultsThirty-seven patients were assessed for eligibility, which represents the total number of c-TA patients being followed by the three specialized medical ambulatory services in Sao Paulo. After exclusions, fourteen c-TA patients (71.4% females) aged 12-25 years were randomly allocated into exercised (n=5) and non-exercised groups (n=9). Exercise did not exacerbate arterial inflammation. In fact, exercised patients had a reduction in the frequency of vessel segments with severe inflammation, whereas the non-exercised patients had an opposite response (P=0.007). Greater improvements in visceral fat, steps per day, functionality and physical component SF-36 were observed in the exercised patients (P ≤ 0.05).ConclusionsExercise is safe and may improve visceral fat, physical activity levels, functionality, and physical component SF-36 in c-TA patients. Thus, exercise arises as a novel, evidence-based intervention to improve general health in c-TA.Clinical Trial Registrationhttps://www.clinicaltrials.gov/ct2/show/NCT03494062?term=NCT03494062&draw=2&rank=1, identifier NCT03494062.

This work presents a methodology for the optimization of protocols applied to pediatric patients who underwent brain and chest computed tomography examinations. The implementation of this methodology aims to reduce the dose of ionizing radiation delivered to patients and the consequent risk associated with radiation, without decreasing the diagnostic image quality. The comparison between the results of CTDIvol (computed tomography dose index) and DLP (dose-length product) dosimetric quantities before the optimization process and their corresponding results after the implementation of the optimization process was done through boxplot graphs. It is noteworthy that the implementation of this methodology allows reductions in the range between 18 and 50% of the dosimetric values evaluated in this study. In addition, the case of brain computed tomography scans, in which the cohort of the evaluated patients is larger, is a highlight, which should also reflect in the reduction of the absorbed radiation dose by this particularly important group of patients.

Objectives To evaluate correlations between DRL quantities (DRLq) stratified into patient size groups for non-contrast chest and abdomen-pelvis CT examinations in adult patients and the corresponding organ doses. Methods This study presents correlations between DRLq  (CTDIvol, DLP and SSDE) stratified into patient size ranges and corresponding organ doses shared in four groups: inside, peripheral, distributed and outside. The demographic, technical and dosimetric parameters were used to identify the influence of these quantities in organ doses. A robust statistical method was implemented in order to establish these correlations and its statistical significance. Results Median values of the grouped organ doses are presented according to the effective diameter ranges. Organ doses in the regions inside the imaged area are higher than the organ doses in peripheral, distributed and outside regions, excepted to the peripheral doses associated with chest examinations. Different levels of statistical significance between organ doses and the DRLq were presented. Conclusions Correlations between DRLq and target-organ doses associated with clinical practice can support guidance’s to the establishment of optimization criteria. SSDE demonstrated to be significant in the evaluation of organ doses is also highlighted. The proposed model allows the design of optimization actions with specific risk-reduction results.

Background: Renal angiomyolipomas hemorrhage is strongly associated with their size and vascular constitution. Since previous studies showed that mTOR inhibitors can differentially act in distinct cell lines, we analyzed the effects of sirolimus on the volume of different components of angiomyolipomas in patients with tuberous sclerosis complex, including vascular structures. We retrospectively analyzed 23 angiomyolipomas from 10 patients treated with sirolimus. An approach based on a Hounsfield-unit threshold was used to classify angiomyolipomas in fat-rich, fat-poor and intermediate-fat tumors, and to categorize tumor compartments in fat rich, fat poor, intermediate fat and highly vascularized. Diameter variations were measured to assess the effects on aneurysmatic/ectatic vascular formations. Results: Volume reduction following treatment with sirolimus was higher in fat-poor than fat-rich angiomyolipomas. Tumor reduction was mainly determined by decrease of the fat-poor and highly-vascularized compartments, with a lesser contribution of the intermediate-fat component, while the volume of the fat-rich compartment increased. Broad liposubstitution was observed in some tumors. Massive reduction of aneurysmatic/ectatic vascular structures was observed, with disappearance of such lesions in most cases. Conclusions: Our study showed that sirolimus reduces the size of angiomyolipomas by decreasing primarily their highly-vascularized and fat-poor compartments. This effect is associated with a remarkable reduction of tumoral aneurysms/ectatic vessels and other vascular structures. Our findings revealed, therefore, the likely mechanism responsible for the reported risk-decreasing effect of mTOR inhibitors on angiomyolipoma bleeding. Our findings also expand the understanding the biology of this tumor, supporting a role for mTOR in maintenance, and maybe assembling, of blood vessels in angiomyolipomas.