Growth abnormalities in children with chronic hepatitis B or C

A machine learning-based SNP-set analysis approach for identifying disease-associated susceptibility loci

Identifying disease-associated susceptibility loci is one of the most pressing and crucial challenges in modeling complex diseases. Existing approaches to biomarker discovery are subject to several limitations including underpowered detection, neglect for variant interactions, and restrictive dependence on prior biological knowledge. Addressing these challenges necessitates more ingenious ways of approaching the "missing heritability" problem. This study aims to discover disease-associated susceptibility loci by augmenting previous genome-wide association study (GWAS) using the integration of random forest and cluster analysis. The proposed integrated framework is applied to a hepatitis B virus surface antigen (HBsAg) seroclearance GWAS data. Multiple cluster analyses were performed on (1) single nucleotide polymorphisms (SNPs) considered significant by GWAS and (2) SNPs with the highest feature importance scores obtained using random forest. The resulting SNP-sets from the cluster analyses were subsequently tested for trait-association. Three susceptibility loci possibly associated with HBsAg seroclearance were identified: (1) SNP rs2399971, (2) gene LINC00578, and (3) locus 11p15. SNP rs2399971 is a biomarker reported in the literature to be significantly associated with HBsAg seroclearance in patients who had received antiviral treatment. The latter two loci are linked with diseases influenced by the presence of hepatitis B virus infection. These findings demonstrate the potential of the proposed integrated framework in identifying disease-associated susceptibility loci. With further validation, results herein could aid in better understanding complex disease etiologies and provide inputs for a more advanced disease risk assessment for patients.

Nutritional disorders resulting from food allergy in children

The elimination of food allergens that contribute essential nutrients in paediatrics may lead to the development of nutritional disorders. The most common nutritional disorders include poor growth, micronutrient deficiencies and feeding difficulties. Of the aforementioned, growth faltering has been well studied and is seen as a common presenting factor in paediatric food allergy. However, the use of different criteria and cut-off values makes it difficult to establish the overall effect. The impact of number and type of foods eliminated and comorbidities has yielded varying results, although there seems to be a trend towards worsening growth with atopic dermatitis and the avoidance of cow's milk. Low micronutrient intake is common in paediatric food allergy; however, a low intake does not necessarily translate into a deficiency as measured by biomarkers. Vitamin D and calcium have been well studied, and a long-lasting impact on bone mineral density has been found. However, other micronutrient deficiencies have also been found and should also be considered. Feeding difficulties is a common complaint in clinical practice, but limited data have been published in food allergy. Poor growth and reflux/vomiting have been shown to be associated with feeding difficulties, in particular in non-IgE-mediated food allergies. There seems to be a long-lasting effect on feeding, in particular in cow's milk allergy, which needs to be taken into account with dietary input. The interplay between growth, feeding difficulties and micronutrient deficiencies has been implied in some studies, but cause and effect is not well established and requires further research.

Assessment of Growth and Development in Children With Hepatitis B Positivity

Background

Chronic infections and liver diseases may influence the growth and development of children by leading to malnutrition. In this study, demographic characteristics, anthropometric measurements and laboratory findings for children with hepatitis B positivity were analyzed.

Methods

A total of 43 cases were admitted to our clinic between January 2012 and February 2013 and detected to have HBsAg positivity.

Results

Malnutrition was detected in 11 cases (25.6%) and obesity in three cases (6.9%). Aspartate aminotransferase (AST) levels were significantly higher in malnourished patients compared to those without malnutrition. The weight to height was significantly higher in patients with positive HBeAg compared to children with negative HBeAg. We found that the weight standard deviation scores (SDS) ratios dropped as alanine aminotransferase (ALT) and AST levels increased and height SDS ratios decreased. In addition, body mass index (BMI) decreased as AST and alpha feto protein (AFP) values increased. While a significant relationship was not detected between insulin-like growth factor binding protein-3 (IGFBP-3) and insulin-like growth factor-1 (IGF-1) and ALT, a significantly negative correlation was detected between IGFBP-3 and IGF-1 and AST. We found a malnutrition rate of 25.6% in children with HBsAg positivity. We also found that weight and height SDS rates decreased as ALT and AST levels increased. In addition, we detected that BMI decreased as AST and AFP values increased.

Conclusion

We consider that hepatic inflammation is the factor that affects growth. Monitoring of growth and development during follow-up of children who are detected to have HBsAg positivity would be beneficial to determine the mechanism and causes of growth retardation.

Body mass index and waist circumference of HIV-infected youth in a Miami cohort: comparison to local and national cohorts

OBJECTIVES

Human immunodeficiency virus (HIV)-infected youth are healthier because of effective antiretroviral therapies. We compared anthropometric measurements and prevalence of overweight and obesity between perinatally HIV-infected youth, a local HIV-uninfected comparison group, and 2007 to 2010 National Health and Nutrition Examination Survey (NHANES) data. In addition, we compared only African American HIV-infected youth with NHANES African Americans.

METHODS

Height, weight, body mass index (BMI), and waist circumference (WC) of HIV-infected youth, aged 10 to 19 years, were compared among groups. BMI percentiles were categorized as underweight (<5%), normal (5% to <85%), overweight (85% to <95%), and obese (≥ 95%). Clinical correlates were modeled as predictors of BMI and WC.

RESULTS

A total of 134 HIV-infected (including 103 African Americans) (mean age 16.5 years), 75 HIV-uninfected (mean age 14.2 years), and 3216 NHANES (including 771 NHANES African Americans) (mean age 15.0 years) youth were included in the analysis. Height and weight z scores of HIV-infected youth were lower than those of HIV-uninfected and NHANES (P ≤ 0.056) youth. BMI, WC, and BMI category were not statistically different between groups. In the HIV-infected African American group, BMI z score was lower (0.49 vs 0.76, P = 0.04) compared with NHANES African Americans. There were no significant predictors of BMI or WC for the HIV-infected group.

CONCLUSIONS

HIV-infected children have similar BMIs and WCs as uninfected children both locally and nationally and show similar high rates of obesity and overweight. When compared with a more racially similar African American national sample, HIV-infected children have a lower BMI, suggesting that there may be persistent anthropometric differences in HIV.

The Possible Role of TLR2 in Chronic Hepatitis B Patients with Precore Mutation

Recognition mechanisms of innate immune response help to improve immunotherapeutic strategies in HBeAg-negative chronic hepatitis B (CHB). Toll-like receptor 2 (TLR2) is an important component of innate immunity. In this study, the frequency of precore mutations of the hepatitis B virus (HBV) and serum TLR2 were evaluated in CHB patients. Fifty-one patients with chronic hepatitis B, negative for HBeAg and detectable HBV DNA, were examined for the presence of mutations in pre-core region of HBV genome by direct sequencing. Serum TLR2 was measured by enzyme-linked immunosorbent assay. Interactions of truncated HBeAg and TLR2 proteins were evaluated with molecular docking software. The G1896A pre-core mutation were detected in 29 (57%) which was significantly associated with higher concentration of serum TLR2 in comparison with patients without this mutation (4.8 ± 2.9 versus 3.4 ± 2.2 ng/mL, P = 0.03). There was also a significant correlation between serum ALT and TLR-2 (r = 0.46; P = 0.01). Docking results illustrated residues within the N-terminus of truncated HBeAg and TLR2, which might facilitate the interaction of these proteins. These findings showed the dominance of G1896A pre-core mutation of HBV variants in this community which was correlated with serum TLR2. Moreover TLR2 is critical for induction of inflammatory cytokines and therefore ALT elevation.