Whole-Body MRI in Children and Adolescents - S1 Guideline. / Ganzkörper-Magnetresonanztomografie im Kindes- und Jugendalter ­ S1-Leitlinie.

Whole-body MRI is an imaging method that uses advanced modern MRI equipment to provide high-resolution images of the entire body. The goal of these guidelines is to specify the indications for which whole-body MRI can be recommended in children and adolescents and to describe the necessary technical requirements. CITATION FORMAT: · Schaefer JF, Berthold LD, Hahn G et al. Whole-Body MRI in Children and Adolescents - S1 Guidelines. Fortschr Röntgenstr 2019; 191: 618 - 625.

Carotid Intima-Media Thickness in Children Treated with Growth Hormone: A Follow-Up Study over Three Years.

BACKGROUND: There is an ongoing discussion whether high doses of growth hormone (GH) may lead to cardiovascular diseases. Therefore, we studied the longitudinal relationships between GH treatment and carotid intima-media thickness (cIMT), which is predictive of the development of atherosclerosis. METHODS: We measured blood pressure, lipids, hemoglobin HbA1c, IGF-1, IGFBP-3, and cIMT in 28 children treated with supraphysiological doses of GH (mean age 9.8 ± 2.2 years, 39% males) and 36 children suffering from GH deficiency (GHD) and treated with physiological doses of GH (mean age 9.7 ± 2.2 years, 72% males) in a longitudinal study over 3 years. RESULTS: The cIMT values did not change significantly in the observation period in children with GHD (Δmaximum and Δmean cIMT 0.0 ± 0.1 mm). The mean (+0.1 ± 0.1 mm) but not the maximum cIMT (0.0 ± 0.1 mm) increased significantly (p = 0.049) in the children treated with supraphysiological doses of GH. Blood pressure, lipids, and HbA1c were not related to cIMT, while IGF-1, IGFBP-3, body mass index expressed as a standard deviation score, and treatment duration correlated significantly with cIMT. CONCLUSIONS: We did not find any robust evidence that GH treatment is associated with changes in cIMT. Further studies are necessary to analyze the impact of IGF-1 and IGFBP-3 concentrations on cIMT.

Carotid intima-media thickness in children treated with growth hormone.

BACKGROUND: There is an ongoing discussion whether high doses of growth hormone (GH) may lead to cardiovascular diseases. Therefore, we studied the relationships between GH treatment and carotid intima-media thickness (cIMT), which is predictive of the development of atherosclerosis. METHODS: We measured cIMT in 38 children with supraphysiological doses of GH (mean age 10.9 ± 2.2 years; 47% male; GH indication: small for gestational age, n = 31; Turner syndrome, n = 5; SHOX deficiency, n = 2) and in 38 age- and gender-matched healthy children without GH treatment. Furthermore, we examined cIMT in 61 children with physiological doses of GH (mean age 12.0 ± 3.1 years; 64% male; GH indication: GH deficiency) and in 61 age- and gender-matched healthy children without GH treatment. Moreover, we analyzed blood pressure, lipids, HbA1c, IGF-1, and IGFBP-3 in children treated with GH. RESULTS: The cIMT levels did not differ significantly between children with and without GH treatment either in high-dose GH treatment or in physiological GH doses. In backwards linear regression analyses, cIMT was significantly related to HbA1c, but not to age, gender, BMI, pubertal stage, indication of GH treatment, duration or doses of GH treatment, IGF-1, IGFBP-3, or to any cardiovascular risk factor. CONCLUSIONS: We found no evidence that GH treatment is associated with changes in cIMT.

Short stature before puberty: which children should be screened for SHOX deficiency?

OBJECTIVE: We studied the prevalence of deficiency in the short stature homeobox containing gene (SHOX) in prepubertal short-statured children and analyzed the clinical and radiological signs. METHODS: Screening for SHOX deficiency was performed in 449 prepubertal short-statured children (54% females, aged 4-10 years) by direct sequencing and multiplex ligation probe-dependent amplification. Children with SHOX deficiency were compared to 1:2 age- and gender-matched prepubertal children without SHOX deficiency with respect to left-hand radiographs and anthropometrics including different ratios to height and proposed scores. RESULTS: We identified 22 (4.9%) patients with SHOX deficiency (64% point mutations). Children with SHOX deficiency demonstrated a mesomelic shortening of extremities. Lower leg lengths but not forearm length was reduced in children <8 years with SHOX deficiency. 36% of all children and none of the children <8 years with SHOX deficiency demonstrated any typical radiologic sign. Increased sitting height-to-height ratio and decreased extremities-to-trunk ratio demonstrated the best positive and negative predictive values to identify SHOX deficiency. CONCLUSIONS: Screening for SHOX deficiency seems rational, especially in children with increased sitting height-to-height ratio or decreased extremities-to-trunk ratio. These criteria were also valid in young children.

Relationship between carotid intima-media thickness and metabolic syndrome in adolescents.

OBJECTIVE: To test the hypothesis that metabolic syndrome (MetS) is more predictive of carotid intima-media thickness (IMT) than the sum of the individual components of MetS. STUDY DESIGN: We analyzed the relationships between 2 definitions of the MetS and IMT in 461 overweight adolescents aged 10-18 years (median body mass index, 28.6 kg/m(2)). We used regression models and receiver operating characteristics (ROCs) for increased IMT (defined as ≥0.7 mm). RESULTS: The prevalence of MetS was 15.0% and 26.9% according to the 2 definitions applied. At the group level, quantitative IMT was associated with body mass index, blood pressure, glucose levels at 2 hours in an oral glucose tolerance test, and with each of the MetS components (all P < .05). At an individual level, using the MetS definitions alone as a diagnostic test for the presence of increased IMT (area under the ROC curve, 0.60-0.66) was inferior when compared with the sum of all individual components (area under the ROC curve, 0.65-0.85). Adding the presence or absence of MetS to the components did not improve the accuracy. CONCLUSION: Overweight adolescents with MetS demonstrated increased IMT values compared with overweight adolescents without MetS. The best model for diagnosing increased IMT was the sum of the quantitative components of MetS. The use of dichotomized variables reduced the diagnostic accuracy. Thus, in clinical practice, treatment of overweight adolescents should be based on weighing cardiovascular risk factors themselves, rather than on the dichotomous variable MetS.

Urgent resection of bleeding congenital mesenchymal chest wall hamartoma in an infant.

We report a case with prenatally diagnosed large cystic-solid mesenchymal chest wall hamartoma. An attempt of conservative management was made however repeated intralesional hemorrhage led to enlargement and severe anemia which required urgent resection at the age of 8 weeks. The infant had an unimpaired development over a follow-up of 4 years.

Fibroblast growth factor 21 (FGF-21) and its relation to obesity, metabolic syndrome, and nonalcoholic fatty liver in children: a longitudinal analysis.

CONTEXT: Fibroblast growth factor 21 (FGF-21), a potent activator of glucose uptake, has been proposed to be related to insulin resistance, metabolic syndrome (MetS), nonalcoholic fatty liver disease (NAFLD), and weight status. OBJECTIVE: Our objective was to study the relationships between FGF-21, parameters of MetS, and NAFLD before and after weight loss in obese children. DESIGN AND SETTING: This was a cross-sectional comparison between obese and normal-weight children and longitudinal 1-yr follow-up study in obese children participating in a lifestyle intervention in a primary care setting. PATIENTS: Patients included 60 obese and 40 lean children of same age, gender, and pubertal stage. INTERVENTION: The outpatient 1-yr intervention program was based on exercise, behavior, and nutrition therapy. MAIN OUTCOMES MEASURES: We evaluated fasting serum FGF-21, weight status [body mass index (BMI) expressed as sd score (SDS)], body fat, insulin resistance index (homeostasis model assessment), leptin, transaminases, free fatty acids (FFA), waist circumference, blood pressure, and lipids. RESULTS: Compared with the normal-weight children, obese children demonstrated significantly (P < 0.001) increased FGF-21, leptin, and homeostasis model assessment levels. FGF-21 was significantly (P < 0.05) correlated to BMI, SDS-BMI, FFA, and leptin both in cross-sectional and longitudinal analyses but not to any additional analyzed parameter. Children with and without MetS or NAFLD did not differ significantly with respect to their FGF-21 concentrations. A decrease of SDS-BMI was associated with a significant (P = 0.038) decrease of FGF-21 levels (mean -34%). CONCLUSIONS: FGF-21 concentrations are reversibly increased in obese children and are related to leptin and FFA. However, our data do not support a significant relationship between FGF-21, insulin resistance, and features of MetS or NAFLD in children.

Treatment of tall stature in boys: comparison of two different treatment regimens.

BACKGROUND: High-dose testosterone treatment is a well-known, though still controversial, therapy in boys with tall stature. METHODS: 161 boys with constitutional tall stature were treated at two different treatment centers (center A 114 patients; center B 47 patients). In center A, boys were treated with 500 mg and in center B with 250 mg testosterone enanthate intramuscularly every 2 weeks. Predicted adult height (PAH) was calculated according to the Bayley/Pinneau method using the Greulich-Pyle method for bone age determination. RESULTS: At onset of treatment, the patients at the two centers did not differ with respect to chronological age (center A 14.2 ± 1.3 years; center B 13.5 ± 1.1 years), height (center A 187.8 ± 7.3 cm; center B 185.5 ± 5.5 cm), bone age (center A 13.8 ± 0.8 years; center B 13.6 ± 0.7 years), or PAH (center A 205.2 ± 5.2 cm; center B 204.8 ± 5.5 cm). Mean treatment duration was significantly longer in center A than in center B (14.2 ± 4.0 vs. 11.3 ± 2.2 months). At the end of the testosterone treatment, PAH did not differ significantly (center A 197.7 ± 5.3 cm; center B 196.1 ± 4.7 cm). The mean reduction in PAH at the end of treatment was 7.6 ± 5.0 cm (center A) and 8.7 ± 5.6 cm (center B) which is ∼50% of the expected growth at onset of treatment. CONCLUSIONS: A testosterone enanthate dose of 250 mg every 2 weeks was as effective in reducing adult height in boys with tall stature as a dose of 500 mg every 2 weeks.

Effect of lifestyle intervention on features of polycystic ovarian syndrome, metabolic syndrome, and intima-media thickness in obese adolescent girls.

CONTEXT: Polycystic ovarian syndrome (PCOS) is associated with cardiovascular risk factors (CRF). Lifestyle intervention is regarded as therapy of choice even if studies in adolescent girls with PCOS are scarce. OBJECTIVE: Our objective was to analyze the impact of lifestyle intervention on menses irregularities, hyperandrogenemia, CRF, and intima-media thickness (IMT) in adolescent girls with PCOS. PATIENTS: Patients included 59 obese girls with PCOS aged 12-18 yr. INTERVENTION: Intervention was a 1-yr lifestyle intervention based on nutrition education, exercise training, and behavior therapy. MAIN OUTCOME MEASURES: Menses cycles, IMT, waist circumference, blood pressure, fasting lipids, insulin, glucose, testosterone, dehydroepiandrosterone sulfate, androstenedione, and SHBG were evaluated. RESULTS: In contrast to the 33 girls without weight loss, the 26 girls reducing their body mass index during the lifestyle intervention (by a mean of -3.9 kg/m(2)) improved most CRF and decreased their IMT (by a mean of -0.01 cm). Testosterone concentrations decreased (by a mean of -0.3 nmol/liter) and SHBG concentrations increased (by a mean of +8 ng/ml) significantly in girls with weight loss in contrast to girls with increasing weight. The prevalence of amenorrhea (-42%) and oligoamenorrhea (-19%) decreased in the girls with weight loss. The changes in insulin in the 1-yr follow-up were significantly correlated to changes in testosterone (r = 0.38; P = 0.002) and SHBG (r = -0.35; P = 0.048). A linear regression model with changes in IMT as dependent variable demonstrated a significant association with changes in blood pressure and weight status but not with changes in testosterone. CONCLUSIONS: Weight loss due to lifestyle intervention is effective to treat menses irregularities, normalize androgens, and improve CRF and IMT in obese adolescent girls with PCOS.

Intima media thickness-related risk factors in childhood obesity.

Macroangiopathy caused by atherosclerosis is one of the major morbidity and mortality factors in obese adults with dyslipidemia, hypertension and disturbed glucose metabolism. However, the onset of these cardiovascular changes is not well established. Measuring the intima- media thickness (IMT) of the common carotid artery, as a non-invasive marker for early atherosclerotic changes, has been reported to be reliable and predictive for later cardiovascular disease. Increased IMT has been reported in children with diabetes mellitus type 1 and 2. IMT was related to both hyperglycaemia and dyslipidemia in these children. Furthermore, children with hypertension demonstrated increased IMT. Moreover, children with familial hypercholesterolemia have higher IMT values as compared to healthy children. Obese children with the features of the metabolic syndrome (MetS) such as hypertension, dyslipidemia, or impaired glucose tolerance also demonstrated increased IMT. A strong association between IMT and parameters of the MetS has been reported for impaired glucose tolerance. Furthermore, increased androgens in girls with polycystic ovarian syndrome (PCOS) are associated with increased IMT measurements. Reduction of overweight and normalization of blood pressure, glucose metabolism and dyslipidemia were associated with a reduction of IMT in children and adolescents. In conclusion, early vascular changes already occur in obese children with MetS suggesting that rather cardiovascular risk factors such as hypertension, dyslipidaemia, or disturbed glucose metabolism are associated to increased IMT than obesity per se. Most importantly, these early changes are reversible if effective therapy of cardiovascular risk factors could be achieved.

Pregnancy-associated plasma protein A in obese children: relationship to markers and risk factors of atherosclerosis and members of the IGF system.

BACKGROUND: Pregnancy-associated plasma protein A (PAPPA) is a large placenta-derived glycoprotein, which serves as a protease of several IGF-binding proteins (IGFBPs). In non-pregnant adults, measurable PAPPA levels were detected and have been implicated in the pathophysiology of atherosclerotic plaques. However, data in children is lacking. OBJECTIVE: To study the relationship between PAPPA, markers of atherosclerosis, and members of the IGF system in pediatric obesity. PATIENTS AND DESIGN: Eighty-two obese and 52 nonobese children and 1-year longitudinal follow-up study for obese cohort. INTERVENTION: Outpatient 1-year intervention program based on exercise, behavior, and nutrition therapy. MAIN OUTCOME MEASURES: Changes in PAPPA levels, carotid intima media thickness (IMT), weight, blood pressure, lipids, metabolic markers, and members of IGF system. RESULTS: Baseline PAPPA (PAPPA(BL)) serum levels did not differ between obese and lean subjects. PAPPA(BL) correlated significantly with IGF1, IGFBP1, and serum cholesterol. During the 1-year-program mean IMT decreased from 0.66 ± 0.01 to 0.63 ± 0.01 mm (P<0.05) and PAPPA from 1.83 ± 0.12 to 1.58 ± 0.11 µU/l (P<0.00). In linear regression analysis with IMT after intervention as dependent variable, PAPPA contributed significantly to the observed variance. The longitudinal change of PAPPA correlated significantly with the change of serum triglycerides. CONCLUSION: In this cohort of obese children, PAPPA serum levels correlated significantly with other cardiovascular risk factors. The lack of a direct correlation between PAPPA and IMT suggests that the described association of atherosclerotic plaques and increased PAPPA levels might reflect an indirect mechanism of PAPPA with cardiovascular risk factors such as serum lipids rather than a direct effect on the vasculature.

Association between androgens, intima-media thickness and the metabolic syndrome in obese adolescent girls.

BACKGROUND: While an association between androgens and the metabolic syndrome (MS) is well established in obese women, studies concerning this relationship are scarce in obese adolescent girls. Therefore, we analysed the relationships between androgens, MS and intima-media thickness (IMT) in this age-group. METHODS: In 160 obese girls (aged 12-18 years, mean BMI: 32.6 +/- 5.0 kg/m((2))), androgens [testosterone, dehydroepiandrosterone sulphate (DHEA-S), androstenedione], SHBG and the components of MS (waist circumference, blood pressure (BP), lipids, uric acid, insulin, glucose, 2 h glucose in oral glucose tolerance test (oGTT)) were studied. Furthermore, IMT was determined in a subgroup of 71 randomly chosen girls. RESULTS: Testosterone correlated significantly to systolic BP (r = 0.20), diastolic BP (r = 0.24), 2 h glucose in oGTT (r = 0.30), triglycerides (r = 0.19), uric acid (r = 0.17), waist circumference (r = 0.25) and IMT (r = 0.54). These relationships (except for waist circumference and uric acid) were independent of BMI and insulin resistance index homeostasis model assessment. In contrast to testosterone, DHEA-S, androstenedione and SHBG showed no or weaker correlations to any parameter of MS. The 48 girls with MS demonstrated significantly higher testosterone (1.8 +/- 0.7 nmol/l; P = 0.025) and DHEA-S (4.7 +/- 2.3 micromol/l; P = 0.008) concentrations as compared with the 112 girls without MS (mean testosterone 1.5 +/- 0.7 nmol/l, mean DHEA-S 3.6 +/- 2.3 micromol/l). CONCLUSIONS: Testosterone was significantly related to MS and its components in obese adolescent girls independently of BMI and insulin resistance. As IMT was significantly associated with testosterone, this supports the clinical relevance of this finding.

Relationships between cardiovascular risk profile, ultrasonographic measurement of intra-abdominal adipose tissue, and waist circumference in obese children.

BACKGROUND & AIMS: Ultrasonographic measurements have been proposed to assess intra-abdominal adipose tissue. The aim of this study was to compare the relationship between waist circumference (WC), ultrasonographic measurements of intra-abdominal adipose tissue (UMA), and cardiovascular risk factors (CRF). METHODS: We determined blood pressure (BP), fasting HDL-cholesterol, LDL-cholesterol, triglycerides, glucose, insulin resistance index HOMA, 2 h glucose in oral glucose tolerance test (oGTT), weight status (SDS-BMI), WC, and UMA in 89 obese children. Furthermore, we analyzed the changes of CRF, SDS-BMI, WC, and UMA in 29 obese children participating in a one-year lifestyle intervention. RESULTS: In stepwise multivariable regression analysis, waist circumference was significantly associated to LDL-cholesterol, triglycerides, HOMA, and systolic blood pressure (adjusted variance (AV) 0.05-0.17). SDS-BMI was significantly related to triglycerides, HDL-cholesterol, 2 h glucose in oGTT, and diastolic blood pressure (AV 0.12-0.15), while UMA was related significantly to HOMA (AV 0.04). The obese children participating in a lifestyle intervention significantly reduced their overweight, which was associated with a significant improvement of most CRF and a reduction of WC and UMA. Changes of WC were significantly correlated to changes of HDL-cholesterol (r=-0.45), HOMA (r=0.37), glucose tolerance (r=0.59), systolic BP (r=0.60), and diastolic BP (r=0.43), while change of SDS-BMI and UMA were not significantly related to any CRF. CONCLUSIONS: Compared to UMA, WC was stronger related to CRF in obese children. Therefore, the simple measurement of WC seems preferable as an indirect marker of CRF.

Precocious pseudopuberty due to autonomous ovarian cysts: a report of ten cases and long-term follow-up.

We report the findings and clinical course of ten girls aged 0.2 to 6.3 years with precocious pseudopuberty due to autonomous ovarian cysts. We found elevated oestrogen levels in five patients and failure of gonadotropin response to GnRH stimulation in four patients during the first episode, of the disease. In one patient, a GnRH stimulation test was not performed. Pelvic ultrasound examination showed large ovarian cysts in all ten patients. Following the initial episode the secondary sexual characteristics of nine patients regressed completely without treatment. The cyst of one girl was removed surgically on demand of her parents. Three girls presented recurrent autonomous ovarian cysts. Two of these girls developed central precocious puberty requiring treatment with a GnRH-agonist after repeated episodes of precocious pseudopuberty. We started treating the third girl with a GnRH agonist after the second relapse of the autonomous ovarian cyst because of rapidly advancing bone age. We conclude that in the majority of cases autonomous ovarian cysts regress spontaneously and that surgery is in general not indicated. Furthermore, autonomous ovarian cysts can relapse before the onset of physiological puberty and accelerate biological maturation leading to central precocious puberty and consequent decrease of height potential.

Relationship between metabolic syndrome definitions for children and adolescents and intima-media thickness.

OBJECTIVE: Several definitions of the metabolic syndrome (MS) have been proposed for children and adolescents. The aim of this study was to analyse whether these definitions are linked to intima-media thickness (IMT), which is predictive for atherosclerosis and later cardiovascular disease. METHODS: The prevalence of the MS according to the different published definitions was studied in 264 Caucasian overweight children and adolescents aged 7-16 years (mean BMI 27.3 kg/m(2)). IMT was related to the occurrence of the MS and its components. RESULTS: IMT was influenced by weight status, waist circumference, fasting glucose levels, glucose levels at 2h in the glucose tolerance test, and blood pressure, but not by lipids, fasting insulin, and insulin resistance index. A significant association between IMT and the definitions of MS by Viner (p=0.019) and Weiss (p<0.001) could be observed in a linear regression analysis, but not between the IMT and other proposed definitions. Impaired glucose tolerance had a positive predictive value of 96% (95% confidence interval: 93-98%) for IMT equal or above the top quartile (>or=0.7 mm), while the positive predictive values for IMT>or=0.7 mm were <50% in the different proposed definition of MS. CONCLUSIONS: Children with impaired glucose tolerance seem to be at increased risk for later cardiovascular diseases. Impaired glucose tolerance demonstrated the strongest association to high IMT far superior to any proposed definition of MS. Furthermore, since the proposed definitions of the MS were not or only weakly related to IMT, outcome driven studies are necessary to prove the concept of the MS in childhood.

Intima-media thickness in obese children before and after weight loss.

OBJECTIVE: Obesity in childhood is related to increased intima-media thickness, a noninvasive marker for early atherosclerotic changes. The objective of this study was to analyze the changes of intima-media thickness in obese children with weight loss. METHODS: We analyzed the changes of intima-media thickness and, as markers of cardiovascular risk factor profile, systolic and diastolic blood pressure, triglycerides, high-density lipoprotein cholesterol, glucose, insulin, and insulin resistance index (homeostasis model analysis) in 56 prepubertal obese children (median: 9 years old) before and after a 1-year outpatient intervention program. The control group consisted of 10 nonobese children of the same age and gender. We determined the carotid intima-media thickness by B-mode ultrasound with a 14-MHz linear transducer. Substantial weight loss was defined by a reduction of overweight of at least 0.5 standard deviation scores in BMI. RESULTS: Obese children demonstrated a significantly thicker intima-media compared with the control group. Furthermore, blood pressure, triglycerides, insulin, and insulin resistance index were significantly higher in obese children, whereas high-density lipoprotein cholesterol was significantly lower. In the 24 obese children with substantial weight loss, intima-media thickness, blood pressure, triglycerides, insulin, and insulin resistance index decreased significantly, whereas high-density lipoprotein cholesterol increased significantly. In the 32 obese children without substantial weight loss, there were no significant changes apart from an increase of insulin and insulin resistance index. CONCLUSIONS: Because obese children demonstrated a thicker intima-media, vascular changes seemed to occur already in childhood obesity. Paralleling the improvement of the cardiovascular risk factor profile, intima-media thickness decreased in obese children with substantial weight loss, suggesting the reversibility of early atherosclerotic changes.

Analysis of the functional muscle-bone unit of the forearm in pediatric renal transplant recipients.

BACKGROUND: Renal transplantation in children and adolescents is associated with various skeletal complications. The incidence of spontaneous fractures appears to be increased, but the reasons for this are not entirely clear. Our objective was therefore to evaluate macroscopic bone architecture, mass, and strength by peripheral quantitative computed tomography (pQCT), a method that is not influenced by size-related artifacts. In addition, we investigated the muscle-bone relationship in these patients because under physiologic conditions bone strength continually adapts to increasing mechanical loads, that is, muscle force. METHODS: In 55 patients (41 males) aged 15.8 +/- 4.1 years, we evaluated in a cross-sectional study 4.9 +/- 3.6 years after renal grafting bone mass, density, geometry, and strength of the radius, as well as forearm muscle size and strength, using pQCT at the proximal and distal radius, radiography of the second metacarpal shaft and hand dynamometry. Data were compared to a large cohort (N= 350) of healthy children. RESULTS: Muscle mass and force were adequate for body size in pediatric renal transplant recipients. However, the radial bone was characterized by an inadequately thin cortex in relation to muscular force, as shown by a reduced height-adjusted cortical thickness both at the proximal (-0.83 +/- 1.12 SDS) and distal radius (-0.52 +/- 1.69 SDS), the metacarpal shaft (-0.54 +/- 1.35 SDS), and by a reduced relative cortical area (-0.90 +/- 1.13 SDS), while the mineralization of trabecular bone was unaltered. As a consequence of cortical thinning, the Strength-Strain Index that reflects the combined strength of trabecular and cortical bone was reduced in these patients. CONCLUSION: While bone mineral density of the forearm is not decreased in pediatric renal transplant recipients, bone strength in relation to muscular force is reduced. This alteration may contribute to the increased propensity for fractures in these patients.

Functional and morphologic evaluation of congenital urinary tract dilatation by using combined static-dynamic MR urography: findings in kidneys with a single collecting system.

PURPOSE: To assess combined static-dynamic magnetic resonance (MR) urography in the evaluation of congenital urinary tract dilatation in infants and children. MATERIALS AND METHODS: Sixty-two patients with urinary tract dilatation underwent prospective examination with combined static-dynamic MR urography. A combination examination involved use of a static T2-weighted three-dimensional inversion-recovery fast spin-echo sequence and a dynamic T1-weighted two-dimensional fast field-echo sequence with gadopentetate dimeglumine-DTPA and furosemide application. Twelve additional patients underwent examination with only static MR urography. Thus, both image quality and morphologic features were assessed in 74 patients with the use of MR urography. The results were compared with those of ultrasonography and, when available, conventional urography or surgery. In 62 patients, the dynamic sequence was used to calculate split renal function from renograms generated from parenchymal regions of interest and to assess urinary excretion from whole-kidney renograms. Results were compared with those of diuretic renal scintigraphy (DRS) for split function (Spearman rank correlation coefficient) and urinary excretion (kappa coefficient). RESULTS: Stenoses at the ureteropelvic (n = 33) and ureterovesical (n = 31) junctions and within the ureter (n = 3) and nonstenotic dilatation (n = 23) were clearly depicted, while the normal urinary tract (n = 51) was depicted in its entirety in 47 of 51 examinations. Image quality was considered good or excellent in 95% of the kidney-ureter units. For split renal function, dynamic MR urography and DRS showed significant correlation (r = 0.92, P <.001). For urinary excretion, MR urography and DRS showed strong agreement (kappa = 0.67), with concordant classification of urinary excretion in 59 (81%) of 73 abnormal kidney-ureter units and in all 47 (100%) normal kidney-ureter units. CONCLUSION: Combined static-dynamic MR urography provides high-quality depiction of the urinary tract in infants and children, while allowing accurate determination of single-kidney function and reliable evaluation of urinary excretion.

Advanced coronary and carotid arteriopathy in young adults with childhood-onset chronic renal failure.

BACKGROUND: Cardiovascular mortality is excessive in young adults with end-stage renal disease (ESRD). The factors contributing to ESRD-related vascular disease are incompletely understood. Young adults with childhood-onset chronic renal failure (CRF) are uniquely suited for risk factor assessment because of their long-term exposure at an age when vascular pathology in the general population is still minimal. METHODS AND RESULTS: We used novel noninvasive technologies to screen for coronary and carotid artery disease in 39 patients with ESRD aged 19 to 39 years with childhood-onset CRF presently treated by dialysis or renal transplantation. Coronary artery calcification burden was assessed by CT scan with ECG gating and the intima-media thickness (IMT) of the carotid arteries by high-resolution ultrasound. Coronary artery calcifications were present in 92% of patients; calcium scores exceeded the 95th age- and sex-specific percentiles >10-fold on average. Carotid IMT was significantly increased compared with matched control subjects. Both coronary calcium scores and IMT were associated with cumulative dialysis and ESRD time and the cumulative serum calcium-phosphate product. Coronary calcium scores were strongly correlated with C-reactive protein and Chlamydia pneumoniae seropositivity, time-averaged mean serum parathyroid hormone, and plasma homocysteine. C-reactive protein and parathyroid hormone independently predicted coronary calcium accumulation. Smoking, obesity, and HbA1c were correlated with IMT in the control subjects but not in the patients. CONCLUSIONS: Young adults with childhood-onset CRF have a high prevalence of arteriopathy associated with indicators of microinflammation, hyperparathyroidism, calcium-phosphate overload, and hyperhomocysteinemia but not traditional atherogenic risk factors. These risk factors persist even after successful renal transplantation.