Clinical and histological features of nonalcoholic fatty liver disease in children

Nonalcoholic fatty liver disease (NAFLD) is becoming more frequently diagnosed as the prevalence of obesity in children increases rapidly.

The aim of this study was to investigate the correlation of clinical findings with histopathologic features in children with NAFLD.

We reviewed the clinical data and liver histology results of children with biopsy-proven NAFLD at Seoul National University Hospital. NAFLD was classified as simple steatosis, type 1 nonalcoholic steatohepatitis (NASH), characterized by ballooning degeneration and perisinusoidal fibrosis, or type 2 NASH, characterized by portal inflammation and portal fibrosis.

Among 80 total patients, 84% were male. All patients were obese or overweight. Insulin resistance was present in 96% of children. Perisinusoidal fibrosis was noted in 45% of children and portal fibrosis was noted in 77%. Simple steatosis was present in 22% of children, type 1 NASH in 34%, and type 2 NASH in 44%. No differences were found among NAFLD subtypes or NAFLD activity score with regard to sex, blood pressure, or levels of aminotransferase, fasting lipid, or insulin. Children with NASH were older and had higher body mass index than those with simple steatosis. Patients with type 2 NASH had higher body mass index and advanced fibrosis compared with patients with type 1 NASH.

Obesity and older age are associated with development of NASH. Type 2 NASH is the most common form and associated with a greater severity of obesity and advanced fibrosis.