Glossary of Terms
Reviewed by: HU Medical Review Board | Last reviewed: August 2024
A
Alanine aminotransferase (ALT)
An enzyme found in the liver that helps convert proteins into energy. Elevated levels in the blood indicate liver damage.1
Ascites
Fluid buildup in the abdomen. Ascites is often due to severe liver disease like cirrhosis.2
Aspartate aminotransferase (AST)
An enzyme found in the liver and other tissues that helps metabolize amino acids. Elevated levels can signal liver or muscle damage.1
B
Bilirubin
A yellow substance produced during the breakdown of red blood cells. Elevated levels of it can indicate liver or bile duct problems.3,4
Biopsy
A medical procedure where a small sample of liver tissue is taken to examine for signs of damage or disease.1,2
C
Cholesterol
A waxy substance in the blood. Cholesterol is essential for building cells. But high levels of cholesterol can be harmful to health.5
Cirrhosis
Advanced liver scarring where normal liver tissue is replaced with scar tissue to the point that the liver cannot heal from the scarring. This leads to impaired liver function.2,5
Computed tomography (CT) scan
A specialized X-ray that provides detailed cross-sectional images of the liver and other organs.1
E
Edema
Swelling in the legs, ankles, and feet. Edema is caused by fluid buildup in the body.2
Elastography
An imaging technique that measures the stiffness of liver tissue. This test helps determine whether there is fibrosis of the liver and if so, how severe it is.1,2
F
Fatty liver
A condition where excess fat builds up in the liver cells, often due to factors like obesity, insulin resistance, or heavy alcohol use. Fat buildup can lead to liver inflammation and damage if not managed.2,5
Fibrosis
Thickening and scarring of the liver.2,5
H
Hepatic encephalopathy
A decline in brain function that occurs when the liver is unable to remove toxins from the blood. This results in the toxins building up in the brain. Symptoms can range from confusion and forgetfulness to slurred speech.2
Hepatitis
Inflammation of the liver. It can be caused by many factors, including infections, toxins, autoimmune diseases, and excessive alcohol use.6
Hepatocellular carcinoma
A type of liver cancer that can develop in people with chronic liver disease, including NASH-related cirrhosis.7
Hepatologist
A doctor who specializes in diagnosing and treating liver diseases.8
I
Inflammation
The body's way of protecting itself when it gets hurt or fighting off infections. Inflammation causes redness, warmth, swelling, and sometimes pain in the affected area. It helps heal the injury or fight off germs. But it can cause problems if it happens too much or lasts too long. Inflammation in the liver can lead to liver damage and impair liver function.5,6
J
Jaundice
A yellowing of the skin and eyes caused by high bilirubin levels. Jaundice is a symptom of the liver not working as it should.2
L
Liver
A vital organ located in the upper right abdomen that performs several essential functions. It removes toxins from the blood, produces bile for digestion, stores nutrients, and regulates metabolism. It plays a key role in maintaining overall health.4
Liver enzymes
Proteins produced by the liver that are released into the blood when the liver is damaged. Common ones include ALT (alanine aminotransferase) and AST (aspartate aminotransferase).1
Liver failure
When the liver loses its ability to function properly. This can lead to the buildup of toxins in the body, impaired metabolism, and potentially life-threatening complications. Liver failure can result from a chronic liver disease, such as NASH, or sudden liver damage.2,5,7
Liver function tests
Blood tests that assess how well the liver is working. They measure levels of liver enzymes, proteins, and bilirubin.1,2
Liver transplant
A surgical procedure to replace a diseased liver with a healthy one from a donor. A liver transplant is considered in severe cases of cirrhosis or liver failure.9
Lobe
Sections of the liver. The liver has 4 lobes: the right, left, caudate, and quadrate lobes.4
M
Magnetic resonance imaging (MRI)
A detailed imaging technique that uses magnetic fields and radio waves to see inside the body. MRI can help detect fibrosis and inflammation of the liver.1,2
MASH
Metabolic dysfunction-associated steatohepatitis. MASH is the new name for NASH. The name change seeks to emphasize the link between metabolic issues – obesity and type 2 diabetes – and liver disease.2,10
MASLD
Metabolic dysfunction-associated steatotic liver disease. MASLD is a newer name for NAFLD.2,10
Metabolic syndrome
A group of conditions including high blood pressure, high blood sugar, excess body fat around the waist, and abnormal cholesterol levels. Metabolic syndrome increases the risk of heart disease, stroke, and type 2 diabetes.2,11
N
NAFLD
A condition where excess fat builds up in the liver without significant alcohol consumption. NAFLD can potentially leading to liver damage.2,5
NASH
A severe form of NAFLD in which liver inflammation and liver damage occur with fat buildup in the liver.2,5
O
Obesity
A condition where a person has excess body fat, which can negatively affect their health. It is often measured by body mass index (BMI). Obesity can increase the risk of diseases such as heart disease, diabetes, high blood pressure, and liver disease.2,5
P
Portal hypertension
Increased blood pressure in the portal vein. It can result from cirrhosis and lead to complications.2
Portal vein
A major blood vessel that carries nutrient-rich blood from the digestive organs to the liver for processing and detoxification. It delivers substances absorbed from the intestines to the liver.4
S
Steatosis
When fat builds up in the liver.2
T
Type 2 diabetes
A chronic condition that involves high blood sugar levels resulting from insulin resistance and not enough insulin production by the pancreas. It is often associated with obesity, lack of physical activity, and genetics. It can lead to health complications – like liver disease – if not managed effectively.2,5,7
U
Ultrasound
An imaging technique that uses sound waves to create pictures of the liver. This helps to detect fat buildup and liver abnormalities.1
W
Weight loss
A key lifestyle change that is recommended for managing NAFLD and NASH. Losing weight can reduce liver fat and inflammation. For those in the early stages of NAFLD and NASH, weight loss can prevent liver damage from getting worse and, in some cases, reverse liver damage.2