Choose the content to read
Nonalcoholic Fatty Liver Disease
Nonalcoholic fatty liver disease (NAFLD) is an abnormal liver condition caused by excessive fat buildup in the liver cells. Fatty liver or hepatic steatosis is associated with obesity and hyperlipidemia or hyperglycemia. In most patients, steatosis does not cause detrimental effects on the liver directly. Despite that, 1 in 3 patients can develop nonalcoholic steatohepatitis or NASH. In addition, long-standing, slowly progressive steatohepatitis results in fibrosis caused by the liver damage repair process. An advanced stage of liver fibrosis leads to cirrhosis and increases the risk of liver cancer.
Although few NAFLD patients develop steatohepatitis, hepatic steatosis is considered a risk factor for cardiovascular complications. Patients with hepatic steatosis usually are obese and have diseases associated with cardiovascular diseases such as hypertension, diabetes, etc.
Risk factors of NAFLD
As previously mentioned, fatty liver is associated with increased body weight; current Western lifestyle and diets are drivers of increased prevalence of metabolic syndrome (having a waist circumference of more than 90 cm in women and 100 cm in men, hypertension, hypertriglyceridemia, and hyperglycemia). These factors play a role in causing increased fat accumulation in the liver and in raising the risk of cardiovascular diseases.
Besides the primary causes, other risk factors for NAFLD include hormonal imbalances and certain medications, such as polycystic ovarian syndrome (PCOS), thyroid disease, hypopituitarism, or underactive pituitary gland, and taking tamoxifen.
Symptoms
Patients with NAFLD or NASH usually don’t have any symptoms. They often are detected during an annual checkup, when liver enzymes are high or liver fat accumulation is evident by an ultrasound scan.
When to see a doctor
Regardless of having no symptoms, it is necessary for patients diagnosed with NAFLD to have a quantitative severity assessment, liver fibrosis measurement in particular. Screenings for other diseases, such as diabetes, hypertension, and hyperlipidemia, are also important. Patients should consult with their doctors for further evaluation.
Diagnosis
Initial screening methods for NAFLD involve abdominal ultrasound to check for liver fat accumulation and liver enzyme testing to screen for steatohepatitis. Depending on the physicians, the additional tests to determine the causes of steatohepatitis may include:
Blood tests
- Liver function tests
- Viral hepatitis B and C screenings
- Multi-panel screenings, e.g., fasting blood sugar, hemoglobin A1c, and lipid profiles.
Measurement of liver fibrosis
One of the standard methods for liver fibrosis assessment is FibroScan or transient elastography. This technique gauges the degree of liver stiffness and transforms it into liver fibrosis quantification crucial for further treatment planning. The new model of FibroScan can also estimate liver steatosis. FibroScan involves placing a transducer on the skin over the liver to transmit and record the reflected sound waves off the liver. It is a simple, quick, and painless procedure.
Another method to measure liver fibrosis is magnetic resonance imaging (MRI), which uses magnetic fields and special equipment to measure the elasticity of the liver, which can transform into measurements of liver fibrosis.
Liver biopsy for tissue examination
Liver biopsy is a less common method nowadays. There are alternative, noninvasive options to this method, which do not cause pain. However, if the cause of steatohepatitis is uncertain, this procedure may be considered. It involves removing the piece of the liver by inserting a biopsy needle and retrieving tissue for microscopic examination.
Treatment
Weight loss is the best and most effective way to treat NAFLD because it can decrease hepatic steatosis, inflammation, and fibrosis in the liver. Losing weight also confers beneficial effects on concurrent diseases such as diabetes, hypertension, and hyperlipidemia. Typically, patients should aim to lose about 5 – 10 percent of their body weight.
