***TASK*** the task is to summarize an input biomedical literature in six sentences 
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    Input: Purpose The object of this study was to assess whether 18F-fluorodeoxyglucose PET/CT ( FDG PET/CT ) provides novel information in patients with Takayasu ’s arteritis ( TA ) in addition to that provided by current activity assessment , to analyse the effects of possible confounders , such as arterial grafts , and to verify whether PET/CT could be informative in lesions < 4 mm thick . Methods We studied 30 patients with TA , evaluated from October 2010 to April 2014 by both PET/CT and magnetic resonance imaging ( MRI ) .  All arterial lesions were evaluated by PET both qualitatively ( positive/negative ) and semiquantitatively ( maximum st and ardized uptake value , SUVmax ) , and the thickness of lesions in the MRI field of view was evaluated . In a per-patient analysis , the relationships between the PET data and acute-phase reactants and NIH criteria for active TA were evaluated . In a per-lesion analysis , the relationships between the PET features of each lesion and MRI morphological data were evaluated . The effects of the presence of arterial grafts were also evaluated . Results Increased FDG uptake was seen in 16 of 30 patients ( 53 % ) and in 46 of 177 vascular lesions ( 26 % ) . Significant periprosthetic FDG uptake was seen in 6 of 7 patients ( 86 % ) with previous vascular surgery and in 10 of 11 of grafts ( 91 % ) . Graft-associated uptake influenced the PET results in three patients ( 10 % ) and the SUVmax values in five patients ( 17 % ) . Of 39 lesions with significant FDG uptake , 15 ( 38 % ) were < 4 mm thick . Lesion thickness was correlated with lesion SUVmax in FDG-avid lesions only . FDG arterial uptake was not associated with systemic inflammation or NIH criteria . Conclusions PET/CT reveals unique and fundamental features of arterial involvement in TA . PET/CT may be useful in the assessment of local inflammatory and vascular remodelling events independent of systemic inflammation during follow-up , even in lesions in which the arterial wall is < 4 mm . The presence of arterial grafts is a potential confounder . Prospect i ve studies are required to correlate PET findings with relevant clinical outcomes Takayasu arteritis is a chronic , idiopathic , inflammatory disease that primarily affects large vessels , such as the aorta and its main branches . The clinical features usually reflect limb or organ ischemia result ing from gradual stenosis of involved arteries . Takayasu arteritis often occurs in females during their reproductive years [ 1 - 6 ] . Much of the literature describing Takayasu arteritis has originated from Asian countries , and the disease was once thought to be restricted to these regions [ 1 - 6 ] . During the past few decades , patients with Takayasu arteritis have been increasingly recognized in Africa , Western Europe , and North America [ 7 - 10 ] . However , experience with this disease in the Western Hemisphere remains anecdotal [ 11 - 17 ] . The estimated incidence rate is 2.6 cases per million persons per year . Our institute has prospect ively studied 60 patients with Takayasu arteritis . This is the largest cohort of patients with Takayasu arteritis thus far studied in the United States . We report the clinical manifestations , treatment , and long-term outcome of patients with Takayasu arteritis . Methods Patients Sixty patients with Takayasu arteritis were seen at the National Institutes of Health from 1970 to 1990 . Patients were recruited as part of vasculitis protocol s and without bias to economic , social , or racial status . Medical care was provided without cost to the patients . The diagnosis was based on the presence of symptoms and signs of ischemic , inflammatory large-vessel disease , as well as supportive arteriographic findings . All patients had periodic arteriographic studies and had abnormalities that included multifocal areas of stenosis or aneurysm formation ( or both ) of the aorta or its primary branches [ or both ] . Other causes of large-vessel abnormalities were excluded based on clinical criteria and , where appropriate , on serologic studies . These include 1 ) inflammatory aortitis [ such as syphilis ; tuberculosis ; systemic lupus erythematosus ; rheumatoid arthritis ; spondyloarthropathies ; Buerger , Behcet , Cogan , and Kawasaki diseases ; and giant cell arteritis ] ; 2 ) developmental anomalies [ such as the Ehlers-Danlos syndrome and the Marfan syndrome ] ; and 3 ) other aortic abnormalities ( such as neurofibromatosis , ergotism , and radiation fibrosis ) . Once enrolled , patients were prospect ively followed and assigned to treatment protocol s if their disease was active . Frequency of follow-up depended on disease activity and treatment and varied from monthly to yearly visits . Each visit included a complete history and physical examination , routine laboratory tests , blood pressure measurements in all four limbs ( cuff or DynamappDoppler ) , electrocardiogram , and chest radiograph . A complete aortogram was done if active , new disease was suspected or if required by specific treatment protocol s every 4 to 6 months . Patients enrolled in the methotrexate protocol had angiographic studies at study entry and 6 months and 12 months after enrollment .  Angiography was done by the intra-arterial injection of approximately 100 mL of iopamidol ( 61 % ; Isovue-300 , Squibbs Diagnostic , New Jersey ) using femoral puncture . Criteria for Disease Activity New onset or worsening of two or more features of Takayasu arteritis ( Table 1 ) defined active disease . Typical angiographic findings of disease are shown in Figure 1 . A clear-cut decrease in symptoms or improved clinical findings or both indicated partial remission or smoldering disease . Complete resolution of all clinical features or their stabilization , in the setting of fixed vascular lesions , was indicative of remission . Table 1 . Criteria for Active Disease in Patients with Takayasu Arteritis * Figure 1 . Angiogram showing critical stenoses . Treatment Patients with active disease were initially treated with oral glucocorticoids at a dose of 1 mg/kg per day for 3 months . If patients could not then be tapered to an alternate-day regimen without disease exacerbation , a cytotoxic agent was added as previously described [ 18 , 19 ] . Briefly , such patients received either cyclophosphamide , azathioprine , or methotrexate . Cyclophosphamide or azathioprine was administered as a daily oral dose of 1 to 2 mg/kg per day in conjunction with daily glucocorticoids . Methotrexate was given once weekly , the oral dose ranging from 0.15 to 0.35 mg/kg . The usual starting dose for methotrexate was about 15 mg/wk , with 2.5-mg increments every 1 to 2 weeks to achieve a maximum tolerated weekly dose of up to 25 mg . If active disease had improved , daily glucocorticoid therapy was tapered to an alternate-day regimen . If disease remained inactive , glucocorticoid therapy was further tapered and stopped . Patients who also received a cytotoxic agent continued that agent alone for 1 year after remission . Then , the cytotoxic agent was tapered ; cyclophosphamide and azathioprine were tapered by decrements of 25 mg/mo , and methotrexate was tapered by 2.5 mg/mo until discontinued . If disease recurred , daily glucocorticoids or a cytotoxic agent ( or both ) were increased or restarted . If the glucocorticoids could not be tapered to an alternate-day regimen within 6 months or could not be discontinued completely within 12 months of starting the cytotoxic agent , then that cytotoxic agent was considered a failure . Such patients were treated with the minimum daily glucocorticoid dose that could control their disease . Human Lymphocyte Antigen Typing Lymphocytes were separated and typed for HLA-A , B , and C. B lymphocytes were obtained for HLA DR , DQ , and DRw typing . Sera or cells were typed by the fluorescent technique ( from the National Institutes of Health ) using a microtoxicity assay with eosin staining [ 20 ] . Antigenic typing complied with guidelines from the International Histocompatibility Workshop . Statistical Methods The frequencies of symptoms and clinical findings were compared for association with and without specific arterial involvement by the Fisher Exact test , with adjustments made for multiple comparisons using the modified Bonferroni method [ 21 ] . Laboratory results observed during active disease and remission were compared using the two-tailed paired t-test . Medians for diagnostic delay and duration of follow-up for pediatric-onset and adult-onset Takayasu arteritis were compared by the Wilcoxon two- sample test . The estimated cumulative occurrences of patient remission and relapse over time were determined by the Kaplan-Meier method [ 22 ] . The distributions of time to response of the two age groups were compared by the log-rank method . The probability that observed results were consistent with reported demographic and HLA markers in the general population [ 23 , 24 ] was tested using binomial confidence intervals . Ninety-five percent confidence intervals ( CIs ) were calculated using observed frequencies in the study group ; CIs that did not include the national percentage were statistically significant ( P < 0.05 ) . Results Sixty unrelated patients with Takayasu arteritis were followed during a median period of 5.3 years ( range , 0.5 to 20 years ) . Fifteen patients were lost to follow-up ; 11 of these were followed for 3 to 19 years . The cohort included 58 females and 2 males . The racial background of the patients was as follows : white , 75 % ; African-American , 11.7 % ; Asian , 10 % ; and American Indian , 3.3 % ; Hispanics made up 7 % of the population . The racial distribution was similar to that reported for the United States in the 1990 Census , except for Asians , who comprised 2.9 % of the normal population but accounted for 10 % of our study group ( P = 0.05 ) [ 21 ] . The median age at onset of first symptoms of the disease was 25 years ( range , 7 to 64 years ) , and 21 patients ( 35 % ) presented in the third decade . Nineteen patients ( 32 % ) were juveniles ( < 20 years ) at disease onset . Eight patients ( 13 % ) had onset of their disease after 40 years of age . The median duration of follow-up for pediatric- and adult-onset patients was similar ( 4.8 compared with 5.4 years , respectively , P > 0.20 ) . Patients often had symptoms for several months before the diagnosis of Takayasu arteritis was made . The median delay between the onset of first symptoms and the diagnosis of disease was 10 months ( range , 0 to 13 years ) . The pediatric patients had a median delay in diagnosis of 19 months , but adults had a delay of only 5 months ( P = 0.01 ) . The diagnosis in 12 patients was not made for at least 3 years , even though 8 had either limb claudication or absent or diminished pulses . The remaining 4 patients had features ( such as headache , hypertension , dizziness , arthritis , and erythema nodosum ) for which an inflammatory or vascular cause was not considered . Six patients ( 10 % ) lacked symptoms at disease onset , but the diagnosis was pursued because of clinical findings of asymmetric blood pressures , absent or diminished peripheral pulses , or a bruit . Clinical Features The clinical features of all 60 patients are shown in Figure 2 . Figure 2 . Frequency of clinical features of Takayasu arteritis at presentation and during the course of disease . Vascular Findings The most common clinical finding was a bruit ( 80 % ) , and the most common site was in the carotid vessels ( 70 % ) . Thirty-three percent of patients had multiple bruits . Femoral ( 3.3 % ) and renal ( 1.7 % ) bruits were uncommon . Claudication and a diminished or absent pulse were more common in the upper limbs ( 62 % and 53 % , respectively ) than in the lower limbs ( 32 % and 15 % , respectively ) . Carotodynia was present in 32 % of patients . Claudication at disease onset was less common in pediatric patients than in adult patients ( 11 % compared with 46 % ) , and this continued throughout the course of disease ( 47 % compared with 81 % , P = 0.02 ) . Lightheadedness or dizziness occurred in one third of the patients . Fifty-seven percent of patients with some degree of vertebral artery stenosis experienced lightheadedness . In contrast , only 23 % of those without vertebral artery disease had lightheadedness ( P = 0.04 ) . Lightheadedness was not associated Aim : To evaluate the feasibility of modifying diuresis renography by the simultaneous administration of Tc-99 m ethylenedicysteine and furosemide in the investigation of hydronephrosis and hydroureteronephrosis in infants and children . Parameters assessed were the diuretic response in normal kidneys and the ability of the F+0 study to differentiate between renal obst 
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Conclusion The CRP concentration only moderately reflects the 18F –  FDG PET vascular positivity in TAK , suggesting dissociated information .