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

Abstract

Nonalcoholic fatty liver disease (NAFLD) is one of the main chronic non-communicable 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 patient lifetimes. We review the similarities and differences of NAFLD between children and adults.

Genetic determinants of steatosis and fibrosis progression in paediatric non‐alcoholic fatty liver disease

“…Since the marked increase in obesity prevalence, non-alcoholic fatty liver disease (NAFLD) has become the most frequent chronic liver disease in adults and children alike. 1 NAFLD is strongly associated with obesity as well as insulin resistance and has been proposed as the hepatic manifestation of the metabolic syndrome. However, marked differences in the prevalence of NAFLD according to ethnicity have highlighted the importance of genetic influence in addition to environmental factors.…”

Hepatic farnesoid X receptor protein level and circulating fibroblast growth factor 19 concentration in children with NAFLD

“…Recent data show a prevalence of paediatric NAFLD of 3%-10%, with a 2:1 male: female ratio, and the prevalence of obesity is up to 70% in children. 1 According to Bellentani et al, 2 the prevalence of NAFLD in obese children living in Western countries, such as Italy, is estimated to be between 40% and 70%. NAFLD represents a spectrum of liver fat-associated disease, ranging from 'simple hepatic steatosis' (abnormal accumulation of fat in more than 5% of the hepatocytes, without evidence of hepatocellular injury or fibrosis) to 'non-alcoholic steatohepatitis' (NASH), which is characterized by the coexistence of hepatic steatosis, inflammation and eventually fibrosis.…”

Hepatic fibrosis in children and adults

“…Similarly, in NASH, which afflicts adults and older children, the response to injury varies with age. Steatosis is more severe in children, and fibrosis and inflammation are distributed differently, found initially primarily in zone 1 (portal) in children and in zone 3 (lobular) in adults . In contrast, the fibrocystic liver diseases, of which ARPKD with congenital hepatic fibrosis is the most common example, produce similar liver responses (massive cholangiocyte proliferation and bile duct dilation with surrounding fibrosis), regardless of the age of disease onset.…”