83 SYMPOSIUM : Gastroenterology & Hepatology Non-Alcoholic Fatty Liver Disease and Childhood Obesity Prashant Mathur, Manoja K Das 1 and Narendra K Arora 2 Indian Council of Medical Research, New Delhi 1 INCLEN Trust, New Delhi 2 Department of Pediatrics, AIIMS & Executive Director, INCLEN Trust, New Delhi. [Received March 3, 2007; Accepted March 19, 2007] ABSTRACT Obesity has emerged as a significant global health problem in the pediatric population. Pediatric liver disease is a serious complication of childhood obesity. Non-alcoholic steatohepatitis (NASH) is an entity in the spectrum of non-alcoholic fatty liver disease (NAFLD) ranges from fat in the liver – simple steatosis, NASH/ steatohepatitis – fat with in.ammation and/or fibrosis to advanced fibrosis and cirrhosis when fat may no longer be present. NASH is associated with obesity, diabetes, insulin resistance (IR), and hypertriglyceridemia. Children get NAFLD, and the incidence of this pediatric liver disease is rising as childhood obesity becomes increasingly prevalent. Although much remains to be learned about pediatric NAFLD, it is already evident that children with NASH risk progressive liver damage, including cirrhosis. Liver biopsy is required for definitive diagnosis, and other causes of fatty liver in childhood must be excluded. Gradual weight loss through increased regular exercise and a low- fat, low–refined carbohydrate diet appears to be effective. Drug treatments are being developed. The important message is that childhood obesity poses important health problems, including but not limited to potentially severe chronic liver disease. Early diagnosis of children who are only overweight is a worthy goal so that strategies to limit obesity can be instituted as early as possible. Identification of genetic risks is important, but management will invariably require changes in environmental factors. In addition to individual treatment, a multifaceted, societal initiative is required for solving the childhood obesity epidemic. [Indian J Pediatr 2007; 74 (4) : 401-407] E-mail: nkamanan@yahoo.com Key words : Childhood obesity; Non-alcoholic fatty liver disease; Epidemiology; Risk factors; Outcome Obesity has emerged as a global epidemic in children with a spectrum of psycho-social and medical consequences manifesting across the lifespan. Adiposity affects almost all organs of body, but some systems like cardiovascular and endocrine are affected to a greater extent than others. Obese children are at higher risk for hypertension, hyperlipidemia, arteriosclerosis, and diabetes mellitus type-2. 1 Chronic liver disease associated with obesity has been identified in adults as a distinct identity since 1970s, and after almost a decade the condition was reported in children and adolescents. Moran et al provided the first report on severe hepatitis and fibrosis associated with obesity in 3 children aged 10- 13 years. 2 Non-Alcoholic Fatty Liver Disease (NAFLD) describes a spectrum of liver disease in persons who have not Correspondence and Reprint requests : Dr. Prof. Narendra K. Arora, Division of Pediatric Gastroenterology, Hepatology and Nutrition, Department of Pediatrics, All India Institute of Medical Sciences, New Delhi-110029 India. consumed alcohol in significant amounts so as to cause liver damage, and in whom no other etiology for fatty liver is present. The pathological spectrum ranges from simple hepatic steatosis, to infiltration by inflammatory cells and mild to moderate fibrosis (Non-alcoholic Steatohepatitis-NAHS) leading to cirrhosis. 3 With advancing fibrosis, the steatotic component diminishes so that in cirrhotic livers fat may no longer be seen. Pathologically, NAFLD is a result of complex hepatocellular metabolic dysfunctions in which insulin action is deranged, leading to deranged metabolism of fat and free fatty acids and subsequent oxidant mediated damage to the hepatocytes. Several factors sustain and amplify this cytotoxic mechanism. It is not clear whether simple hepatic steatosis in children is benign or evolves to NASH over time. Usually the abnormality of liver is discovered incidentally while evaluating a child for pain abdomen or some other unrelated ailment. Childhood presents a unique period of growth and development where the causes of fatty liver are enumerable as compared to adults. Broadly, they can be divided into: Indian Journal of Pediatrics, Volume 74—April, 2007 401