Sections View Full Chapter Figures Tables Videos Annotate Full Chapter Figures Tables Videos Supplementary Content +++ Key Features +++ Essentials of Diagnosis ++ Hepatomegaly in patient with body mass index more than 95th percentile Elevated alanine aminotransferase (ALT) > aspartate aminotransferase (AST) Detection of fatty infiltration of the liver on ultrasound Histologic evidence of fat in the liver Insulin resistance +++ General Considerations ++ A clinicopathologic condition of abnormal hepatic fat deposition in the absence of alcohol Most common cause of abnormal liver function tests in the United States Ranges from bland steatosis, to fat and inflammation, with or without scarring (also referred to as nonalcoholic steatohepatitis, NASH) to cirrhosis Incidence correlates with obesity; in the United States, Up to 10% of all children are affected 38% of obese children are affected Comorbidites include Type 2 diabetes mellitus Hypertension Hyperlipidemia Metabolic syndrome Most children are 11–13 years old at diagnosis Males (ratio of 2:1) and Hispanics at highest risk +++ Clinical Findings +++ Symptoms and Signs ++ Most patients are asymptomatic Nonalcoholic fatty liver disease (NAFLD) often discovered on routine screening Some patients may complain of fatigue or right upper quadrant pain Obesity and insulin resistance are known risk factors Moderate sleep apnea is also common Obstructive sleep apnea and hypoxia appear to contribute to disease severity Asymptomatic soft hepatomegaly may be present, but abdominal adiposity may make this difficult to assess Physical findings of insulin resistance (acanthosis nigricans and a buffalo hump) are frequently present +++ Differential Diagnosis ++ Wilson disease Hereditary fructose intolerance Tyrosinemia Hepatitis caused by hepatitis C virus Cystic fibrosis Fatty acid oxidation defects Kwashiorkor Reye syndrome Respiratory chain defects Total parenteral nutrition–associated liver disease Toxic hepatopathy (ethanol and others) +++ Diagnosis +++ Laboratory Findings ++ AST and ALT May be normal Do not identify bland steatosis If elevated, typically elevated < 1.5 times the upper limit of normal, with an ALT:AST ratio of > 1 Alkaline phosphatase and GGT may be mildly elevated Bilirubin is normal Hyperglycemia and hyperlipidemia are also common +++ Imaging ++ Ultrasonography, CT scan, or MRI can be used to confirm fatty infiltration of the liver While ultrasound costs less and lacks radiation exposure, it may be insensitive in severe central adiposity or if < 30% steatosis is present Radiologic imaging cannot distinguish bland steatosis from the more severe NASH or reliably identify fibrosis Transient elastography is a research tool that shows promise in estimating hepatic fibrosis +++ Diagnostic Procedure ++ Liver biopsy may show Microvesicular or macrovesicular steatosis Hepatocyte ballooning Mallory bodies Lobular or portal inflammation Varying degrees of fibrosis +++ Treatment ++ Lifestyle modifications, through both dietary changes and exercise, to induce slow weight loss A 10% decrease in body weight can significantly improve NAFLD ... Your MyAccess profile is currently affiliated with '[InstitutionA]' and is in the process of switching affiliations to '[InstitutionB]'. Please click ‘Continue’ to continue the affiliation switch, otherwise click ‘Cancel’ to cancel signing in. Get Free Access Through Your Institution Learn how to see if your library subscribes to McGraw Hill Medical products. Subscribe: Institutional or Individual Sign In Username Error: Please enter User Name Password Error: Please enter Password Forgot Username? Forgot Password? Sign in via OpenAthens Sign in via Shibboleth