Thyroid dysfunction and hepatic steatosis in overweight children and adolescents

BACKGROUND

Overt or subclinical hypothyroidism is a common finding in adult populations affected by non-alcoholic fatty liver disease (NAFLD). Currently, there are only sparse data available on the association of thyroid dysfunction and NAFLD in obese children and adolescents.

OBJECTIVE

The study aims to investigate the association of thyroid function test values with NAFLD and metabolic risk factors in a population of obese children and adolescents.

METHODS

A total of 332 overweight and obese children and adolescents (170 girls) aged between 10 and 19 years were analysed. Subjects underwent ultrasound examination of the liver. Thyroid function was evaluated by laboratory determination of thyroid-stimulating hormone (TSH), total triiodothyronine (T3) and total thyroxine levels. All included subjects were either euthyroid or had subclinical hypothyroidism (TSH > 4 μU mL^-1 , normal thyroxine). Further metabolic profiling included the determination of lipid status, insulin and liver function tests. Anthropometric parameters body mass index, waist and hip circumference were documented.

RESULTS

The prevalence of hepatic steatosis was 29.8%. Subjects with NAFLD had significantly higher TSH levels than those without (p = 0.0007). After dividing TSH values into quartiles, both univariate and multivariate analyses (adjusted for age, body mass index-standard deviation scores and stage of puberty) showed a significant association with hepatic steatosis (p < 0.05).

CONCLUSION

Taking possible variables into consideration, our results show that there is a significant association between hepatic steatosis and the TSH levels in obese children and adolescents. Mild thyroid dysfunction may therefore have a role in determining an unfavourable metabolic profile in obese children and adolescents.

Comparison of Two High-End Ultrasound Systems for Contrast-Enhanced Ultrasound Quantification of Mural Microvascularity in Crohn's Disease

PURPOSE

To verify the reproducibility of contrast-enhanced ultrasound (CEUS) quantification results of two different high-end ultrasound systems and to evaluate the clinical utility of the method in patients with Crohn's disease (CD).

MATERIALS AND METHODS

18 patients with histologically confirmed CD (36.8 % women, 63.2 % men; mean age 43.7 ± 14.1 years) and wall segments thicker than 5 mm were recruited. CEUS quantification and conventional ultrasound investigation were performed under standardized settings using Toshiba Aplio500 and Siemens Acuson S3000 high-end ultrasound systems. CEUS was performed at a low mechanical index of 0.1 after bolus application of 4.8 ml of SonoVue(®) contrast medium. The recorded DICOM clips were quantified using VueBox(®) (version 4.3) calculating 11 quantitative parameters. Subsequently, CEUS quantification and conventional ultrasound results were analyzed.

RESULTS

Correlation of quantitative parameters between the Aplio500 and AcusonS3000 systems for peak enhancement (PE), rise time (RT), wash-in-rate (WiR) and quality of fit (QOF) yielded significance levels of p < 0.05 and p < 0.0001 for wash-in-wash-out area under the curve (WiWoAUC). Spearman rank test showed moderate levels of correlation for PE, RT, WiR and QOF (r = 0.5, 0.49, 0.49 and 0.5 respectively), and high correlation for WiWoAUC (r = 0.89) between the two ultrasound systems.

CONCLUSION

Due to multiple uncontrollable affecting factors, the method of CEUS quantification by VueBox in the intestine cannot be recommended for device-independent multicenter studies. Therefore we suggest to use identical ultrasound systems and probes as well as to establish adequate reference ROIS, like a AIF-ROI.

A Nonclassical Monocyte Phenotype in Peripheral Blood is Associated with Nonalcoholic Fatty Liver Disease: A Report from an EMIL Subcohort

Nonalcoholic fatty liver disease (NAFLD) as the prototypic hepatic manifestation of metabolic syndrome is an independent risk factor for cardiovascular disease. Our study was designed to investigate the association between NAFLD and alteration in monocyte subsets as hallmark of cardiovascular disease. Seventy-three "Echinococcus Multilocularis and other medical diseases in Leutkirch" (EMIL) population-based cohort participants (mean observation period 11 years) were selected to study their monocyte phenotype by multiparameter flow cytometry. NAFLD was diagnosed using standard ultrasound based criteria excluding other causes of fatty liver disease. Three monocyte subsets ("classical" CD14++ CD16-, "intermediate" CD14++  CD16+, "nonclassical" CD14+CD16++  monocytes), and surface markers (CD36 and CD9) were determined. Classical risk markers covering inflammatory and dysmetabolic characters were also determined. Forty-three out of 73 subjects revealed a stable clinical phenotype, namely 17 subjects revealed NAFLD, whereas 26 subjects showed no fatty liver disease. Compared to the nonfatty liver group, the nonclassical monocyte fraction (p=0.049), total monocyte fraction and count were increased in NAFLD probands (p=0.028, and 0.035, respectively), while classical monocyte fraction (p=0.034) was decreased. Total monocyte fraction, nonclassical monocyte fraction, and waist circumstance were independent risk factors for NAFLD. The nonclassical monocyte fraction and classical monocyte fraction were significantly correlated with waist-to-hip ratio. This pilot long-term follow-up study suggests that nonclassical monocyte fraction and total monocyte fraction might have potential as a prognostic and modifiable biomarker in NFALD patients. This novel marker set might therefore be of interest to monitor druggable inflammatory pathways in individuals with hepatic manifestation of the metabolic syndrome.

Sonographically measured suprailiac adipose tissue is a useful predictor of non-alcoholic fatty liver disease in obese children and adolescents

OBJECTIVE

The objective of the present study was to identify ultrasonographic and anthropometric parameters that are highly associated with the presence of non-alcoholic fatty liver disease (NAFLD) in overweight children and adolescents.

METHODS

A total of 447 overweight children and adolescents (body mass index, 32.4 ± 5.2 kg m(-2) ; mean age, 14.2 ± 1.9 years; range 10.1-20.3 years) were analysed. Subjects underwent ultrasound examination of the liver as well as ultrasonographic measurement of the amount of adipose tissue overlying the biceps brachii and triceps brachii muscles, and of subscapular, suprailiac and abdominal subcutaneous adipose tissue and intra-abdominal depth. Anthropometric parameters such as body mass index, waist and hip circumference were documented.

RESULTS

The prevalence of NAFLD was 27.1%; it was significantly associated with the above-cited anthropometric parameters (P < 0.001). Ultrasonographic findings identified a significant association between NAFLD and the amount of subscapular, suprailiac and abdominal subcutaneous adipose tissue (P < 0.001) as well as between NAFLD and intra-abdominal depth (P < 0.001). Stepwise logistic regression analysis showed only intra-abdominal depth for both gender and the deposit of subcutaneous suprailiac adipose tissue in females to be independent predictors of NAFLD.

CONCLUSIONS

In overweight children and adolescents, we identified intra-abdominal depth for both gender and the ultrasonographically easily determined subcutaneous suprailiac adipose tissue in females as independent predictor of NAFLD.

Influence of plasma cortisol and other laboratory parameters on nonalcoholic Fatty liver disease

The objective of the present study was to analyse the association between the plasma cortisol concentration and nonalcoholic fatty liver disease (NAFLD). A total of 1 326 subjects (age 18-65 years) were examined in the context of an epidemiological study of a population-based random sample. Medical history and anthropometric data of 662 women and 664 men were documented. In addition, laboratory examinations were performed and the fat concentration of the liver was estimated by ultrasound examination. Mean cortisol concentration in plasma was 260.4±156.8 nmol/l for women and 295.8±161.2 nmol/l for men. NAFLD was identified in 17.7% in women and 35.1% in men. Plasma cortisol concentration showed no association with the existence of NAFLD. NAFLD correlated positive with age, body-mass index (BMI), waist-to-hip-ratio (WHR), alanine aminotransferase (ALT), and triglycerides. The present study failed to establish any association of plasma cortisol concentrations and NAFLD.

Determination of vitality of liver lesions by alveolar echinococcosis

Objective of our study is qualitative and quantitative comparison of contrast enhanced ultrasound (CEUS) and 18F-FDG PETCT in monitoring hepatic alveolar echinococcosis (HAE). Parasitic liver lesions were examined regarding number, size, morphology, vascularization and metabolic activity. Patients, methods: 36 patients with medicallytreated HAE were included in this prospective clinical study. Abdominal ultrasound and CEUS were carried out using ultrasound contrast amplifier SonoVue®. As part of monitoring, patients were examined by 18F-FDG-PET-CT. Quantitative analysis of CEUS was performed using the Software Vue- Box™ Quantification Toolbox. Maximum contrast enhancement in lesions peak enhancement (PE) was used as parameter. For quantification of 18F-FDG PET-CT, maximum Standardized Uptake Value (SUVmax) of lesions was specified and statistically compared with PE. Results: 18F-FDG uptake in parasitic liver lesions was diagnosed by 18F-FDG PET-CT in 32 of 36 patients. Vascularization of liver lesions was detected by CEUS in 22 of 32 FDG-positive patients with sensitivity of 69% and specificity of 100%. Mean maximum diameter of lesions was 69.5mm in CEUS and 63.7mm in B-scan ultrasound (p < 0.0001). No significant correlation was found between SUVmax and PE (p = 0.8879). Conclusion: In comparison to FDG PET-CT, the gold standard for detecting viable lesions by depicting metabolism, CEUS detects viable lesions with high specificity and moderate sensitivity by showing vascularization. CEUS must be regarded as an important tool in monitoring HAE. Dimensions of parasitic lesions are displayed more precisely through CEUS than in B-scan. With currently available methods, CEUS quantification has no benefit in monitoring HAE lesions in daily clinical practice.

Associations of fatty liver disease and other factors affecting serum SHBG concentrations: a population based study on 1657 subjects

Sex hormone binding globulin (SHBG) is a glycoprotein expressed predominantly in the hepatocytes. It regulates the transport of sex steroid hormones in the blood stream to their target tissues. The expression of the SHBG gene is subject to multifactorial regulation including hormonal, metabolic, and nutritional aspects. Against this background, we investigated the effect of fatty liver and metabolic syndrome, together with other parameters, on serum SHBG concentrations in a population-based cohort in Germany. This cross-sectional study included 870 women and 787 men (average age 42.3±12.8 years), who underwent ultrasound screening for fatty liver in addition to providing a complete medical history and undergoing physical and laboratory examination. Fatty liver was diagnosed on ultrasound criteria in 159 women (18.3%) and 287 men (36.5%). Fatty liver was shown to exert a significant influence on serum SHBG concentrations in men and in premenopausal women. Men with grade 1 fatty liver had a 1.96-fold increased risk (95%-confidence interval=1.28-3.02; p=0.0022) and postmenopausal women with grade 1 fatty liver a 2.4-fold risk (95%-confidence interval=1.11-5.27; p=0.0267) for low SHBG concentrations. Among metabolic parameters, HDL-C represented as affecting factor in men (p=0.0058) and premenopausal women (p=0.0002), while cholesterol only showed an association in premenopausal women (p=0.0439) and triglyceride in postmenopausal women (p=0.0436). No association of concentrations of SHBG and metabolic syndrome was observed. Age, BMI and waist-to-hip ratio also influence the SHBG concentration. Based on these findings, we conclude that fat accumulation in the liver influences SHBG concentrations in men and premenopausal women.