The full spectrum of hepatic steatosis in children

Distinctive Features of Hepatic Steatosis in Children: Is It Primary or Secondary to Inborn Errors of Metabolism?

PURPOSE

The incidence of hepatic steatosis among children has been increasing; however, data distinguishing simple steatosis from a more complex disorder are lacking.

METHODS

This study identified the etiologies resulting in hepatic steatosis through a retrospective review of pediatric liver biopsies performed in the last 10 years. A total of 158 patients with hepatic steatosis proven by histopathological evaluation were enrolled in the study, and baseline demographic features, anthropometric measurements, physical examination findings, laboratory data, ultrasonographic findings, and liver histopathologies were noted.

RESULTS

The two most common diagnoses were inborn errors of metabolism (IEM) (52.5%) and nonalcoholic fatty liver disease/steatohepatitis (NAFLD/NASH) (29.7%). The three most common diseases in the IEM group were glycogen storage disorders, Wilson's disease, and mitochondrial disease. The rates of consanguineous marriage (75.6%; odds ratio [OR], 26.040) and positive family history (26.5%; OR, 8.115) were significantly higher (p=0.002, p<0.001, respectively) in the IEM group than those in the NAFLD/NASH group. Younger age (p=0.001), normal anthropometric measurements (p=0.03), increased aspartate aminotransferase levels (p<0.001), triglyceride levels (p=0.001), and cholestatic biochemical parameters with disrupted liver function tests, as well as severe liver destruction of hepatic architecture, cholestasis, fibrosis, and nodule formation, were also common in the IEM group.

CONCLUSION

Parents with consanguinity and positive family history, together with clinical and biochemical findings, may provide a high index of suspicion for IEM to distinguish primary steatosis from the consequence of a more complex disorder.

Causes of secondary non-alcoholic fatty liver disease in non-obese children below 10 years

This study aimed to detect etiologies and histopathological features of non-alcoholic fatty liver disease (NAFLD) in Egyptian children < 10 years from hepatologist perspectives. Infants and children below 10 years of age with biopsy-proven fatty liver over a 6-year period were included. NAFLD activity score was used to detect the presence of non-alcoholic steatohepatitis (NASH). The study included 66 cases whose age ranged between 5 months and 10 years. Transaminases were elevated in 60% patients. Glycogen storage disease (GSD) was the most common diagnosis (33.3%) followed by hepatitis C virus (HCV) (10.6%) and Chanarin-Dorfman syndrome (CDS) (9.1%). The cause of steatosis could not be identified in 28.8% of cases. There was a higher prevalence of secondary causes of NAFLD in patients < 10 years. Liver histopathological examination revealed preserved lobular architecture in 75.7% with minimal-to-mild fibrosis in 79%. Steatosis was macrovesicular in all specimens (severe steatosis in 39.4%). Four patients had NASH. Higher degree of steatosis was associated with more severe fibrosis (P = 0.01).Conclusion: GSD was the commonest cause of secondary NAFLD in Egyptian children < 10 years followed by HCV and CDS with higher degrees of steatosis in younger patients. The degree of fibrosis was significantly related to the degree of steatosis.What is Known:• Primary non-alcoholic fatty liver disease (NAFLD) is rare in children aged less than 10 years.• Secondary causes of NAFLD should be considered in patients who do not have traditional risk factors.What is New:• Glycogen storage disease, hepatitis C virus, and Chanarin-Dorfman syndrome are the commonest causes of secondary NAFLD in Egyptian children (< 10 years) with higher degrees of steatosis in younger patients.• The degree of liver fibrosis is significantly related to the degree of steatosis.

Severe Fat Accumulation in Multiple Organs in Pediatric Autopsies: An Uncommon but Significant Finding

Background The observation of fat accumulation in different organs at pediatric autopsy may help determine the cause of death. However, a comprehensive study on fat accumulation and related etiologies is still lacking. Aim To investigate the incidence of fat accumulation in different organs in pediatric autopsies and their relevance to the cause of death. Methods From February 2004 until March 2015, fat accumulation was assessed in 561 routinely performed pediatric autopsies in our center. Age at death ranged from 14 weeks of gestation for fetuses to 16 years. Samples of liver, heart, kidney, and muscle were stained with Oil-Red-O and scored for fat accumulation by one pediatric pathologist. Results Fat accumulation in ≥1 organ(s) was present in 132 (39.8%) of 332 prenatal cases. Only 3 (0.9%) had fat accumulation in all 4 organs. For postnatal cases, fat accumulation in ≥1 organ(s) was present in 106 (46.3%) of 229 postnatal cases. Only 12 (5.2%) had fat accumulation in all 4 organs. Fat accumulation was mostly seen in liver, both in prenatal and postnatal cases. Fatty acid oxidation disorders were the only cause of death associated with severe fat accumulation in all 4 organs. No other etiologies could be linked directly to distribution or severity of fat accumulation. Conclusion Severe fat accumulation in at least 4 organs is a rare finding in pediatric autopsies, whereas fat accumulation in only the liver is relatively common. Severe fat accumulation in both liver, muscle, kidney, and heart was only seen in cases with fatty acid oxidation disorders.

Comparison of the Phenotype and Approach to Pediatric vs Adult Patients With Nonalcoholic Fatty Liver Disease

Nonalcoholic fatty liver disease (NAFLD) is one of the main chronic noncommunicable diseases in Westernized societies; its worldwide prevalence has doubled during the last 20 years. NAFLD has serious health implications not only for adults, but also for children. However, pediatric NAFLD is not only an important global problem in itself, but it is likely to be associated with increases in comorbidities, such as metabolic syndrome and cardiovascular diseases. There are several differences between NAFLD in children and adults, and it is not clear whether the disease observed in children is the initial phase of a process that progresses with age. The increasing prevalence of pediatric NAFLD has serious implications for the future adult population requiring appropriate action. Studies of NAFLD progression, pathogenesis, and management should evaluate disease phenotypes in children and follow these over the patient's lifetime. We review the similarities and differences of NAFLD between children and adults.