Fatty liver in childhood

Clinical and Histologic Liver Improvement in Siblings With Lysosomal Acid Lipase Deficiency After Enzyme Replacement

OBJECTIVES

To assess the effect of long-term (104 weeks) treatment with recombinant sebelipase alpha (rhSA) on serum lipid and hepatic transaminase levels, and liver histopathology in 4 siblings diagnosed with lysosomal acid lipase deficiency (LAL-D).

METHODS

Four male siblings from the same nonconsanguineous parents were diagnosed with the late-onset phenotype of LAL-D in 2015. Liver specimens were obtained by biopsy at baseline and after 104 weeks of enzyme replacement with rhSA (1 mg/kg, IV, every 2 weeks). Hepatic transaminase, lipid and lipoprotein levels were assessed at baseline and sequentially every 16 weeks for 104 weeks. Hepatic steatosis was evaluated from hematoxylin and eosin-stained specimens, and fibrosis was evaluated (Metavir-scoring system) from trichrome-stained specimens obtained at baseline and following 104 weeks of treatment with rhSA.

RESULTS

All 4 siblings had improvement in their serum lipid and hepatic transaminase levels after treatment with rhSA. Alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels decreased from baseline by an average of 47% and 56%, respectively. The fasting triglyceride and low-density lipoprotein cholesterol (LDL-C) levels decreased from baseline by an average of 43% and 60%, respectively. Hepatic steatosis decreased from baseline grade 3 to posttreatment grade 1. Hepatic fibrosis did not advance following 104 weeks of treatment with rhSA and regressed in 1 sibling.

CONCLUSIONS

Treatment with rhSA for 104 weeks in 4 siblings with LAL-D demonstrated improvement in their hepatic transaminase and serum lipid levels, accompanied by reduction of hepatic steatosis and no progression of fibrosis.

Histopathologic Analysis in Sudden Infant and Child Deaths: A Practical Approach

The forensic pathologist responsible for sudden unexpected death (SUD) investigation in the pediatric setting faces many challenges. It usually takes many years to obtain reasonable experience and exposure to the wide variety of diseases that may present as SUD in a pediatric context, and to appreciate the differences in the etiology and clinical context between the pediatric and adult SUD setting. In pediatric SUD, it is necessary to conduct a systematic, pediatric-focused autopsy investigation including extensive histopathological assessment and ancillary testing. Postmortem histologic findings in the context of SUD in the pediatric population are often subtle and distinctly different from those seen in the adult population. The pathologist must have an understanding of both developmental and pathological processes in order to correctly interpret the findings during a pediatric autopsy. A system-based, histopathology-focused review of common entities, normal variants, and incidental findings that can prove challenging will be discussed. For the forensic pathologist tasked with pediatric SUD autopsies, development of a strong collaborative relationship with a pediatric pathologist and/or neuropathologist to assist with histopathological analysis is strongly endorsed.

Utilization of animal models to investigate nonalcoholic steatohepatitis-associated hepatocellular carcinoma

Nonalcoholic fatty liver disease (NAFLD) comprises a spectrum of liver disorders with fat accumulation from simple fatty liver, nonalcoholic steatohepatitis (NASH), fibrosis/cirrhosis and NAFLD/NASH-associated hepatocellular carcinoma (HCC). NASH is a progressive form of NAFLD and requires medical attention. One of 5-10 NASH patients may progress to end-state liver disease (ESLD or cirrhosis) in 5-10 years; meanwhile, life-threatening complications of ESLD and HCC account for major mortality. An increasing burden of NAFLD in clinics, elucidation of its pathogenesis and progression, and assessment of the efficacy of potential therapeutics demand reliable animal models. Most NASH-associated HCC occurs in cirrhotic subjects; however, HCC does appear in NASH patients without cirrhosis. Lipotoxicity, oxidant stress, insulin resistance, endoplasmic reticulum stress, altered adipokine and lymphokine profiles and gut microbiome changes affect NAFLD progression and constitute key pathobiologic interplays. How these factors promote malignant transformation in a microenvironment of steatotic inflammation and fibrosis/cirrhosis, and lead to development of neoplasms is one of critical questions faced in the hepatology field. The present review summarizes the characteristics of emerging rodent NASH-HCC models, and discusses the challenges in utilizing these models to unveil the mysteries of NASH-associated HCC development.

Early redox imbalance is associated with liver dysfunction at weaning in overfed rats

Neonatal overfeeding induced by litter size reduction leads to further obesity and other metabolic disorders, such as liver oxidative stress and microsteatosis at adulthood. We hypothesized that overfeeding causes an early redox imbalance at weaning, which could programme the animals to future liver dysfunction. Thus, we studied lipogenesis, adipogenesis, catecholamine status and oxidative balance in weaned overfed pups. To induce early overfeeding, litters were adjusted to three pups at the 3rd day of lactation (SL group). The control group contained 10 pups per litter until weaning (NL group). Peripheral autonomic nerve function was determined in vivo at 21 days old. Thereafter, pups were killed for further analysis. Differences were considered significant when P < 0.05. The SL pups presented with a higher visceral adipocyte area, higher content of lipogenic enzymes (ACC, FAS) and with a lower content of adipogenic factors (CEBP, PPARγ) in visceral adipose tissue (VAT). Although autonomic nerve activity and adrenal catecholamine production were not significantly altered, catecholamine receptor (β3ADR) content was lower in VAT. The SL pups also presented with higher triglyceride, PPARγ, PPARα and PGC1α contents in liver. In plasma and liver, the SL pups showed an oxidative imbalance, with higher lipid peroxidation and protein oxidation. The SL group presented with a higher serum alanine aminotransferase (ALT). The early increase in lipogenesis in adipose tissue and liver in weaned overfed rats suggests that the higher oxidative stress and lower catecholamine content in VAT are associated with the early development of liver dysfunction and adipocyte hypertrophy.

Unusual glycogenic hepatopathy causing abnormal liver enzymes in a morbidly obese adolescent with well-controlled type 2 diabetes: resolved after A1c was normalized by metformin

We report, for the first time, a case of an accumulation of glycogen in the liver causing elevation of liver enzymes in a 15-year-old morbidly obese adolescent male with well-controlled type 2 diabetes. Notably, the patient did not have poorly controlled type 1 diabetes and did not require insulin. After normalization of the A1c with metformin, elevated liver enzymes returned to normal.

Paediatric non-alcoholic fatty liver disease: a practical overview for non-specialists

Non-alcoholic fatty liver disease (NAFLD) is the most common paediatric liver disease with a prevalence of almost 10%; therefore, the majority of affected patients are under the care of general practitioners and non-specialists. The condition is caused by central obesity with insulin resistance with additional factors influencing inflammatory activity (steatohepatitis). Ongoing inflammation leads to fibrosis and end-stage liver disease, though this will usually occur after children have transitioned into adult care. However, their main morbidity and mortality is from type 2 diabetes and complications of atherosclerosis. The minority of children undergo biopsy but currently there is no other method to accurately assess the stage of disease. Management is focused at weight loss through a combination of diet and exercise. Here, we present a current review of paediatric NAFLD aimed at non-specialists, with practice points for implementation.

Abdominal Subcutaneous Fat Thickness Measured by Ultrasonography Correlates with Hyperlipidemia and Steatohepatitis in Obese Children

PURPOSE

The aim of this study is to evaluate the relationship between abdominal subcutaneous fat thickness measured by ultrasonography (US) and serum lipid profile and liver transaminases in obese children.

METHODS

One hundred and sixty-six children diagnosed with obesity from May 2001 to December 2013 were included in this study. Data on serum lipid profile and liver transaminases were collected from clinical records. Abdominal subcutaneous fat thickness and grade of hepatic steatosis were evaluated by US.

RESULTS

Of the 166 children, 107 were diagnosed with hepatic steatosis by US, 46 with grade I, 56 with grade II, and five children with grade III. According to the grade of hepatic steasosis, the average values of midline abdominal subcutaneous fat thickness and right flank abdominal subcutaneous fat thickness measured 2.9±0.8 cm and 1.9±0.7 cm in the normal group, 3.3±0.8 cm and 2.0±0.7 cm in grade I, 3.8±0.8 cm and 2.3±0.8 cm in grade II, and 4.1±0.8 cm and 2.8±1.4 cm in grade III, respectively. Abdominal subcutaneous fat thickness correlated with grade of hepatic steatosis (p<0.01). In addition, abdominal subcutaneous fat thickness correlated with concentration of serum lipids and liver transaminases in the age group of 12-14 years (p<0.01).

CONCLUSION

Abdominal subcutaneous fat thickness measured by US can be used as a reliable predictor of possible hyperlipidemia and steatohepatitis in children, especially during the adolescent stage.

Bergamot polyphenol fraction prevents nonalcoholic fatty liver disease via stimulation of lipophagy in cafeteria diet-induced rat model of metabolic syndrome

Nonalcoholic fatty liver disease (NAFLD) is the most common liver disease in industrialized countries. Defective autophagy of lipid droplets (LDs) in hepatocytes, also known as lipophagy, has recently been identified as a possible pathophysiological mechanism of NAFLD. Experimental and epidemiological evidence suggests that dietary polyphenols may prevent NAFLD. To address this hypothesis and analyze the underlying mechanisms, we supplemented bergamot polyphenol fraction (BPF) to cafeteria (CAF) diet-fed rats, a good model for pediatric metabolic syndrome and NAFLD. BPF treatment (50 mg/kg/day supplemented with drinking water, 3 months) potently counteracted the pathogenic increase of serum triglycerides and had moderate effects on blood glucose and obesity in this animal model. Importantly, BPF strongly reduced hepatic steatosis as documented by a significant decrease in total lipid content (-41.3% ± 12% S.E.M.), ultrasound examination and histological analysis of liver sections. The morphometric analysis of oil-red stained sections confirmed a dramatic reduction in LDs parameters such as total LD area (48.5% ± 15% S.E.M.) in hepatocytes from CAF+BPF rats. BPF-treated livers showed increased levels of LC3 and Beclin 1 and reduction of SQSTM1/p62, suggesting autophagy stimulation. Consistent with BPF stimulation of lipophagy, higher levels of LC3II were found in the LD subcellular fractions of BPF-expose livers. This study demonstrates that the liver and its lipid metabolism are the main targets of bergamot flavonoids, supporting the concept that supplementation of BPF is an effective strategy to prevent NAFLD.