Q: Doctor, I have heard that fatty liver occurs in obese adults but my child is only 10 years old.
A: Non-alcoholic fatty liver disease (NAFLD), often referred to as fatty liver, is the number one cause of chronic liver disease in children in U.S., and in adults, probably across the globe. Fatty liver is the single most common reason for a liver transplantation in the adult population.
The incidence of fatty liver has paralleled the rise of obesity in our children and adult population. Over the last decade, the age where we have started to diagnose fatty liver has steadily declined from the teenagers to now as young as 5-to-6 years old.
Why is this happening? Clearly obesity, especially sugar laden diets and beverages are to blame. The recently documented rapid rise in weight in children during the pandemic has not helped. We are seeing the incidence of fatty liver sky-rocket. And as we see obesity rates climb in younger children, we expect to see more fatty liver in these young children.
The diagnosis of fatty liver is suspected in children who are obese and have other symptoms that is referred to as “metabolic”syndrome including high blood pressure (yes – high blood pressure in children!), diabetes akin to diabetes seen in older obese individuals, high cholesterol and triglyceride levels, sleep disorders specifically obstructive sleep apnea, and polycystic ovarian syndrome in girls. The diagnosis comes on liver tests and supplemented with ultrasound – though they may not always go hand in hand. Usually there are no symptoms of fatty liver in children – and hence it often goes undetected.
Does every obese child have fatty liver? No, but unfortunately a good number do. And we cannot tell without some basic investigations if a child has fatty liver or not. Yes, in some cases we can suspect it on the grounds that they have an enlarged liver on physical examination.
Why worry about fatty liver? In a small number of children, fatty liver can lead to hepatitis, i.e. inflammation in the liver and this is referred to as NASH – Non-alcoholic steatohepatitis. NASH results in breakdown of the liver cells and replacement by scar tissue – this over a period of years and decades can lead to decline in the liver functions and ultimately liver failure. The higher the liver enzymes, higher is the risk for NASH. There is a higher risk of developing liver cancer as well.
Keep in mind that there are other causes of fat in the liver and these need to be excluded, for e.g. hepatitis B and C or Wilson’s disease to name a few – the latter being a condition resulting in too much copper accumulation in the liver. The tests to look for these conditions, need to be decided by your pediatrician and pediatric gastroenterologists. Lastly, a very small percentage of children develop fatty liver and they are not fat or do not have another reason that we can identify by the barrage of tests we have in our arsenal.
How do you diagnose fatty liver? Confirmation comes on a liver biopsy, but we do not recommend a liver biopsy for everyone. It is recommended in only those children whose liver enzymes are very high or there is a suspicion of another condition ongoing that we have not been able to identify by other blood tests or there is no improvement with decrease in weight. Hence, in practice, diagnosis of fatty liver remains a diagnosis of exclusion i.e. exclusion of other causes that increase liver enzymes.
What can be done about fatty liver? The first step is to suspect fatty liver and that can be easily accomplished by a combination of physical examination and a blood test/radiological examination like an ultrasound. We should be actively looking for it in obese children or overweight children who show other features of “metabolic syndrome.” Newer imaging modalities using special ultrasound techniques and MRI are under investigation.
Once a diagnosis has been made, and specifically other conditions excluded, treatment is begun.
The current treatment for NAFLD and NASH is controlling body mass index. There are no medications recommended,at least in children, except some experts suggest vitamin E for NASH, though its utility is unclear.
The critical thing to do is to avoid sugar-sweetened beverages and aim for a 10% weight reduction using lifestyle modifications, diet, exercise, good sleep hygiene being the key factors.
Our job really is prevention of fatty liver and if present, control it to avoid ongoing liver damage. So in essence, maintain a healthy body weight and start by eliminating sugar sweetened beverages.
Pankaj Vohra is a Pediatric Gastroenterologist at UNM. Please send your questions to email@example.com.