Noninvasive Tests for Nonalcoholic Fatty Liver Disease

Introduction

The liver is an important organ that performs various functions. It is situated in the upper right side of the abdomen and is the largest internal organ that is indulged in various tasks to maintain the overall health of an individual. It plays a key role in metabolism by converting the nutrients consumed from the food into energy and storing them for later use. It is also involved in processing proteins, fats, and carbohydrates by regulating sugar levels. It is a storage organ for various vitamins and minerals. It additionally synthesizes the proteins required for blood clotting. It also detoxifies harmful substances that break from the body and converts them into less toxic substances, which can be eliminated through bile or urine. Diagnosing liver conditions at an earlier stage can aid with prompt treatment.

What Is Fatty Liver Disease?

Fatty liver is a common medical condition caused by the storage of extra fat in the liver. Most people do not pose any symptoms as it does not cause any serious consequences. In a few cases, fatty liver may result in damaging the liver. It is possible to change fatty liver with lifestyle modifications. Usually, healthy livers contain small amounts of fat, but if the fat levels reach over 5 % to 10 %, it may result in fatty liver disease. Fatty liver usually does not cause any serious problems, but for some individuals, it may progress and worsen over time. The fatty liver progresses through three stages:

• Inflammation of the liver damages the surrounding tissue, resulting in steatohepatitis.

• Formation of scar tissues in the damaged liver.

• Extensive scar tissue is generally replaced by healthy tissue if the liver is damaged. If the condition progresses further, it may cause cirrhosis of the liver. Cirrhosis occurs due to extensive liver damage, which may eventually slow down the liver’s normal function. It may, at times, block the liver resulting in liver failure or liver cancer.

Fatty liver disease can be broadly classified into the following types:

• Alcohol-induced fatty liver.

• Non-alcohol related fatty liver.

What Are the Causes of Fatty Liver Disease?

Fatty liver disease may affect individuals with the following traits:

• Individuals who have completed menopause.

• Individuals with high levels of fat and obesity.

• High blood pressure.

• Diabetes.

• Obstructive sleep apnea.

What Are the Symptoms of Fatty Liver Disease?

The symptoms of fatty liver are mentioned below:

• Abdominal pain.

• Nausea.

• Weight loss.

• Jaundice.

• Swollen abdomen and legs.

• Edema.

• Extreme tiredness.

• Weakness.

What Is Non-alcoholic Fatty Liver Disease?

A condition of the liver in which there is excess fat accumulation in the liver cells, which is unrelated to alcohol consumption, is called non-alcoholic fatty liver disease. It is considered one of the common liver disorders in patients with obesity and insulin resistance. It comprises a spectrum of conditions which includes fatty liver and is characterized by liver inflammation and liver fibrosis. The exact cause of the condition is not clearly known. It is believed to result from a combination of conditions like genetic, environmental, and lifestyle conditions. Abdominal obesity is the key contributor.

Other risk factors for this condition are type-2 diabetes and high blood pressure. Usually, the condition does not present with any symptoms in the early stages and is an incidental finding during a routine examination. The management of the condition involves lifestyle modifications and consuming a healthy diet, and engaging in regular physical activity. In addition, it is important for patients with obesity to lose excess fat and manage underlying conditions like diabetes and high blood pressure. Monitoring the liver functions is crucial to prevent any disease progression.

How Is Fatty Liver Diagnosed?

Individuals with fatty liver may not present with many symptoms. So it is crucial to undergo various diagnostic tests to confirm the presence of fatty liver. Usually, high levels of enzymes are noticed in blood tests which may indicate liver ailments; elevated liver enzymes clearly indicate that the liver tissue is damaged. An ultrasound of the liver may be performed to understand the extent of the damage. In addition, a liver biopsy may be performed to determine how far the liver disease has progressed.

What Are the Noninvasive Tests for Nonalcoholic Fatty Liver Disease?

Nonalcoholic fatty liver clearly indicates that the individual is susceptible to fatty liver for reasons other than alcohol. Various non-invasive tests aid in diagnosing and assessing the severity of the disease. Some of the common noninvasive tests are mentioned below:

• Ultrasound - It is an imaging technique that helps to identify liver defects; it provides a clear picture of the fat accumulation by measuring the brightness or echogenicity of the liver. Just like any other test, ultrasound has certain limitations in accurately quantifying the degree of damage and may be hard to diagnose in overweight individuals or people with significant fibrosis.

• Fibroscan - This method helps to measure liver stiffness and correlates the level of fibrosis. It helps to understand the severity of liver fibrosis. It additionally helps differentiate between simple and complex fibrosis.
• Fatty Liver Index - It calculates routine blood tests like triglycerides, body mass index, and waist circumference. It helps provide a rough estimate of liver fat and identifies individuals with the risk of noninvasive fatty liver disease.
• Magnetic Resonance Imaging - It combines magnetic and mechanical waves to assess liver fitness. It provides a measurement of liver fat, thereby enabling assessment and monitoring of the condition.
• Magnetic Resonance Elastography - This method also uses magnetic resonance to provide information about liver stiffness and severity of fibrosis.

Conclusion

In conclusion, non-alcoholic fatty liver disease is characterized by excess fat accumulation in the liver cells. It is generally associated with conditions like obesity, insulin resistance, and metabolic syndrome; The risk factors include high blood pressure and diabetes. Usually, the symptoms are not noticeable and may proceed to advanced stages resulting in liver cirrhosis or liver failure. The noninvasive tests help to diagnose the existing condition thoroughly and help evaluate the extent of liver disease without any pain. This gives the medical practitioner a clear idea to plan the treatment according to the needs of each individual.