Nonalcoholic Fatty Liver Disease

Abstract

On the basis of strong research and consensus, nonalcoholic fatty liver disease (NAFLD) is the most common liver disease in children and is soon to be the most common indication for liver transplantation in adults. Although the disease begins as simple steatosis, some patients may progress to nonalcoholic steatohepatitis (NASH) and cirrhosis, making early identification and treatment critical.• The diagnosis of NAFLD can be challenging because patients are typically asymptomatic, with no major clinical symptoms of liver disease. Overweight and obese children are at the highest risk for disease. (1)(2)• On the basis of moderate research and consensus, serum ALT is usually mildly elevated but is an imperfect test with a low sensitivity for detecting NAFLD at commonly used thresholds.(10) Liver biopsy is still considered the gold standard for diagnosis but is too invasive for population-level screening and is often used selectively. Novel, noninvasive diagnostic modalities and serum biomarkers are currently being studied but warrant further validation, especially in children.• On the basis of moderate research and consensus, assessing serum liver tests in any overweight or obese child is reasonable.Liver disease should be suspected if the serum ALT is ‡22 U/L(0.37 mkat/L) in girls and ‡25 U/L (0.42 mkat/L) in boys. (10)Subspecialist referral should be considered for those with a normal BMI, persistent ALT elevation longer than 6 months,specific symptoms of advanced liver disease such as splenomegaly, or concerning laboratory findings on selected screening tests.• On the basis of strong research evidence, weight loss is the most efficacious treatment for NAFLD.• On the basis of some research and consensus, initiation of vitamin E therapy (400 IU BID) may be started, although its use probably should be restricted to those children with biopsy-proven disease. (12)• On the basis of some research and consensus, novel elastography-based imaging modalities are being studied in children and several drugs show promise in treating NAFLD.

Non-alcoholic fatty liver disease: a new epidemic in children

“…Each polymorphism is involved in a different stage and, in the future, this disease pathophysiology may be considered a "multiple stage hypothesis". 1,8,[12][13][14] …”

“…Insulin resistance, dyslipemia, and hyperuricemia may serve as guiding parameters for metabolic syndrome. 12,15,16 Waist circumference measurement (measured at the edge of the iliac crests) is an important anthropometric parameter to identify central fat accumulation and, if increased, it may predict the risk of insulin resistance and metabolic syndrome.…”

“…However, an ALT finding is not sensitive or specific to NAFLD, given that its value may fluctuate and even be normal in patients with NAFLD, NASH, or cirrhosis. 8,12,17 A liver biopsy is the gold standard for NAFLD diagnosis and helps to differentiate simple steatosis from NASH, establish the degree of fibrosis, and make a differential diagnosis. However, it is an invasive, relatively costly procedure associated with an uncommon though significant number of complications.…”

“…To this end, numerous biomarkers have been studied, but none has been accurate enough so far. 7,8,12,16 Liver ultrasound is one of the most commonly diagnostic imaging tests used; it is the initial test done in patients suspected of NAFLD. It is a very attractive study because there is no radiation involved.…”

“…Ultrasound effectiveness is limited in morbidly obese patients. [12][13][14][15][16] A computed tomography (CT) may help to diagnose hepatic steatosis. A CT is more specific than an ultrasound, but it is not recommended for routine use because of radiation exposure.…”