Nonalcoholic steatohepatitis (NASH) is a type of Nonalcoholic Fatty Liver Disease (NAFLD) in which a child has inflammation and liver damage in addition to fat in the liver. This article discusses the AIG study along with the management of NAFLD in children. 

The observations of the AIG study were commonly seen in the US and Europe earlier but are now becoming common here too. The junk food children are consuming is largely the reason.

A recent study by AIIMS, New Delhi also pointed out a 30% prevalence of liver disease in the general population, including children. It showed a comparatively lower occurrence of NAFLD among children in government schools.

Nonalcoholic Fatty Liver Disease (NAFLD) and NASH in children

Definition and facts

1. Nonalcoholic fatty liver disease (NAFLD), defined as an abnormal hepatic accumulation of macrovesicular fat in the absence of other etiologies, such as infection, autoimmune processes, hepatotoxic drugs, and storage disorders, is the most common cause of liver disease in children and teenagers.
2. NAFLD is also the most common cause of liver transplant in young adults (<50 years) in the United States, surpassing hepatitis C in 2019.
3. NAFLD is a spectrum of diseases, ranging from isolated steatosis with >5% hepatic steatosis, to nonalcoholic steatohepatitis (NASH), presence of steatosis, hepatocellular inflammation and injury, to fibrosis, and finally, to cirrhosis.
4. If cirrhosis leads to liver failure, a liver transplant may be needed.

Risk factors for NAFLD in children

1. The most significant risk factor for NAFLD is obesity.
2. In a 2019 study of 408 children with obesity using whole liver magnetic resonance imaging–proton density fat fraction, the prevalence rate of NAFLD was 26.0% or roughly one in every four children.
3. NAFLD also occurs in children without obesity.
4. Studies have also demonstrated that a child’s in-utero environment influences the development of NAFLD. Compared with children with normal birth weight, children with low birth weight and high birth weight may have an increased risk for the development of NAFLD.
5. NAFLD is heritable.
6. Children with NAFLD have higher rates of dyslipidemia, hypertriglyceridemia, hypertension, diabetes, and cardiac ventricular dysfunction.
7. Children may present with acanthosis nigricans as a manifestation of insulin resistance.
8. A recent prospective study of 160 adolescents with biopsy-proven NAFLD demonstrated a higher-than-expected incidence of anxiety and depression than the general population, suggesting that mental health disorders may also be associated with NAFLD in children.

Risk factors For NASH/Fibrosis

1. Prediabetes or type 2 diabetes.
2. Birth weight- A high birth weight is associated with higher odds for NASH and low birth weight is associated with higher rates of advanced fibrosis.
3. Dysbiosis of the microbiome - Patients with NASH had the lowest diversity in their microbiome.
4. Hypothalamic dysfunction and panhypopituitarism - Patients with panhypopituitarism have increased leptin levels, which leads to increased tumour necrosis factor-alpha levels and a proinflammatory and fibrotic environment.
5. Obstructive sleep apnea and hypoxemia.

Symptoms

1. Nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH) typically cause few or no symptoms.
2. When symptoms are present, right upper quadrant pain has been thought to be a possible result of the hepatic capsule stretching from hepatic fat deposition, leading to hepatomegaly and/or elevated alanine aminotransferase (ALT).
3. However, in these cases, NAFLD may be an incidental finding.
4. When an overweight or obese patient has an ALT greater than or equal to 2 times the upper limit of normal (ULN), evaluation for other causes of liver disease is recommended before a diagnosis of NAFLD can be made.

Diagnosis

1. Medical and family history.
2. Physical examination.
3. Blood tests for liver enzymes, especially alanine aminotransferase (ALT) and aspartate aminotransferase (AST); for other indicators of liver disease; and for indicators of other conditions, such as infection, autoimmune disease, metabolic or genetic disorders.
4. The Pediatric NAFLD Fibrosis Score (PNFS)
5. Imaging tests such as: 

• USG Abdomen
• FibroScan
• Magnetic resonance imaging (MRI) and magnetic resonance elastography (MRE)
• Liver biopsy to diagnose NAFLD and tell the difference between nonalcoholic fatty liver (NAFL) and nonalcoholic steatohepatitis (NASH).

Treatment

No medicines have been approved to treat NAFLD in children.

Eating, diet and nutrition

The first line of treatment for NAFLD is weight loss through the following: 

• Lifestyle changes
• Focusing on nutrition
• Physical activity
• Sleep

Research on adults with NAFLD has found that a 10 per cent reduction in weight is associated with a 90 per cent resolution of the liver disease.

Disclaimer- The views and opinions expressed in this article are those of the author and do not necessarily reflect the official policy or position of M3 India.

About the author of this article: Dr Jimmy Patel is a practising gastroenterologist in Chennai.