Liver Function Test: MCQ Quiz

The given question states that the highest elevations with AST (Aspartate Aminotransferase) are seen in viral hepatitis. AST is an enzyme that is released into the bloodstream when there is damage to the liver. Viral hepatitis is a viral infection that specifically targets the liver, causing inflammation and damage. Therefore, it is expected to have high levels of AST in viral hepatitis cases.

Unconjugated jaundice is the result of hemolysis. Hemolysis refers to the breakdown of red blood cells, which leads to the release of bilirubin. In cases of excessive hemolysis, the liver may not be able to process the bilirubin effectively, resulting in its accumulation in the bloodstream and causing jaundice.

Bilirubin is responsible for the yellow coloring in jaundice. Jaundice occurs when there is a buildup of bilirubin in the blood, causing the skin and eyes to appear yellow. Bilirubin is a yellow pigment that is produced when red blood cells break down. It is then processed by the liver and excreted in bile. When the liver is unable to properly process bilirubin, it accumulates in the body, leading to jaundice.

Albumin is a protein produced by the liver that plays a crucial role in transporting unconjugated bilirubin to the liver. Unconjugated bilirubin is a waste product produced by the breakdown of red blood cells. It is insoluble in water and needs to be bound to albumin in order to be transported through the bloodstream to the liver, where it can be further processed and eliminated from the body. Therefore, albumin is responsible for the transport of unconjugated bilirubin to the liver for further metabolism and excretion.

Conjugated bilirubin, a product of the breakdown of hemoglobin, is further metabolized in the intestines to form urobilinogen. This conversion occurs through the action of intestinal bacteria. Urobilinogen can then be further processed in the body, with some being reabsorbed into the bloodstream and excreted in urine, while the rest is eliminated in feces. Therefore, the statement that conjugated bilirubin is converted to urobilinogen in the intestines is true.

An increase in total bilirubin, especially direct bilirubin, is indicative of pancreatitis. Bilirubin is a yellow pigment produced by the breakdown of red blood cells. In pancreatitis, the inflammation of the pancreas can cause obstruction of the bile duct, leading to impaired bilirubin excretion. This results in an increase in total bilirubin levels, with a greater elevation in direct bilirubin, which is the form conjugated in the liver. Therefore, an elevated total bilirubin, especially direct bilirubin, is a characteristic finding in pancreatitis.

Jaundice caused by an obstructive pathology of the biliary tree is known as post hepatic. This term refers to a condition where there is a blockage in the biliary system, preventing the flow of bile from the liver to the intestine. This obstruction can occur at the level of the bile ducts outside the liver, such as in the common bile duct or the gallbladder, causing bile to accumulate in the liver and leading to jaundice.

Deposits of bilirubin within the skin, mucus membranes, and in the whites of the eyes is not known as juxtaposition. Juxtaposition refers to the act of placing two things close together for comparison or contrast. Bilirubin deposits in these areas are actually a symptom of a medical condition called jaundice. Jaundice occurs when there is an excess of bilirubin in the bloodstream, causing a yellowing of the skin, mucus membranes, and eyes. Therefore, the correct answer is False.

Cirrhosis of the liver, obstruction, and hepatitis can cause elevations in AST levels. This means that these conditions can lead to increased levels of the enzyme aspartate aminotransferase (AST) in the blood. Therefore, the statement that cirrhosis of the liver, obstruction, and hepatitis are examples of AST elevations is true.

Prehepatic jaundice refers to a type of jaundice that occurs before the liver. It is caused by excessive destruction of red blood cells (RBCs), as seen in conditions like sickle cell anemia. In prehepatic jaundice, the elevated levels of bilirubin in the blood are not due to liver dysfunction, so the levels of ALT (alanine aminotransferase), a liver enzyme, do not rise. This is because the liver is functioning normally, but the increased breakdown of RBCs leads to an increased production of bilirubin.

ALP (alkaline phosphatase) is increased in conditions causing biliary tract obstruction, with elevations proportional to the degree of obstruction. Biliary tract obstruction refers to the blockage of the bile ducts, which can occur due to various reasons such as gallstones, tumors, or strictures. When the bile ducts are obstructed, the flow of bile is disrupted, leading to an accumulation of bile in the liver. This accumulation causes an increase in ALP levels as the enzyme is released from the liver cells into the bloodstream. Therefore, in cases of biliary tract obstruction, ALP levels are elevated.

ALP, also known as alkaline phosphatase, is a group of enzymes primarily found in bone, liver, intestines, and placenta. These enzymes play a crucial role in various biological processes, including bone mineralization, liver function, and nutrient absorption in the intestines. Therefore, ALP is present in these specific organs and tissues to support their respective functions.

Unconjugated

AST (aspartate aminotransferase) is an enzyme that is found in various tissues of the body. It is especially abundant in tissues such as the liver, heart, skeletal muscles, and kidneys. Therefore, the correct answer is "Tissue" because AST has a wide distribution throughout different tissues of the body.

The gallbladder is a small organ located beneath the liver that stores bile produced by the liver. Obstructive jaundice occurs when there is a blockage in the bile ducts, preventing the flow of bile from the liver to the small intestine. The most common cause of obstructive jaundice is the presence of gallstones in the gallbladder or bile ducts. These stones can obstruct the normal flow of bile, leading to the accumulation of bilirubin in the bloodstream and causing jaundice. Therefore, the gallbladder is a common cause of obstructive jaundice.

The prehepatic pattern for serum/plasma is characterized by high total bilirubin (tBili) levels and normal direct bilirubin (dBili) levels. This pattern suggests that there is an increased production or excessive breakdown of red blood cells, leading to an elevated level of unconjugated bilirubin (indirect bilirubin). However, the liver is still able to effectively conjugate the bilirubin, resulting in normal levels of direct bilirubin.

In metastatic disease of the liver, AST (aspartate aminotransferase) levels are typically higher than ALT (alanine aminotransferase) levels. This is because AST is found in many tissues throughout the body, including the liver, heart, and muscles. On the other hand, ALT is predominantly found in the liver. Therefore, when the liver is affected by metastatic disease, there is a greater release of AST into the bloodstream compared to ALT.

In post hepatic jaundice, the obstruction of bile flow occurs after the liver. As a result, the levels of alkaline phosphatase (ALP) rise significantly, not alanine aminotransferase (ALT). ALT is primarily found in liver cells and is more commonly elevated in hepatocellular jaundice. Therefore, the statement that ALT levels rise markedly in post hepatic jaundice is false.

In obstructive jaundice, the direct bilirubin (dBili) should make up 100% of the total bilirubin (tBili). This is because obstructive jaundice is caused by a blockage in the bile ducts, preventing the flow of bilirubin from the liver to the intestines. As a result, the conjugated bilirubin (direct bilirubin) accumulates in the blood, leading to elevated levels of dBili. In this condition, the indirect bilirubin (unconjugated bilirubin) cannot be converted into direct bilirubin and therefore, it is not present in obstructive jaundice.

AST, or aspartate aminotransferase, is an enzyme that is present in various organs of the body. It is commonly found in the liver, heart, skeletal muscles, and brain. It is not typically found in organs such as the spleen or intestines.