Abstract

Metabolic dysfunction-associated steatotic liver disease (MASLD), previously known as non-alcoholic fatty liver disease, is the most common cause of chronic liver disease in children. MASLD encompasses a spectrum of liver disease and can be severe, with 10% of affected children presenting with advanced fibrosis. While biopsy remains the most accurate method for diagnosing and staging the disease, MRI proton density fat fraction and magnetic resonance elastography are the most reliable non-invasive measures for assessing steatosis and fibrosis, respectively. MASLD is associated with multiple comorbidities including type 2 diabetes, hypertension, dyslipidaemia, decreased bone mineral density, obstructive sleep apnoea, anxiety and depression. Currently, there are no pharmacological treatments available for children, highlighting the urgent need for paediatric clinical trials. A diet low in free sugars is promising for reducing steatosis and decreasing alanine aminotransferase, a surrogate marker for hepatic inflammation. Emerging data indicate that steatosis can be present in children under 6 years of age, which was previously considered rare. The intricate interplay of genetics may inform future therapeutics and prognostication, with the PNPLA3 gene showing the most evidence for association with the risk and severity of steatotic liver disease and steatohepatitis. MASLD is a complex disease affecting one in ten children and is associated with increased early mortality risk. More dedicated studies are needed in children to advance our understanding of this disease and find effective treatments.