Albumin and Hypoalbuminemia

Study Notes

Albumin

Albumin is produced exclusively in the liver and comprises about half of the blood serum protein.
Causes of hypoalbuminemia include decreased hepatic synthesis, increased protein losses, kidney disease, protein-losing enteropathy, and severe burns.
Decreased serum albumin levels are not seen in acute liver failure because it takes several weeks of impaired albumin production before the serum albumin level drops.

Bilirubin

Bilirubin is an orange-yellow pigment found in bile, produced from the breakdown of hemoglobin in red blood cells.
Metabolism of bilirubin involves breaking down hemoglobin into heme, which is then converted into unconjugated bilirubin (indirect bilirubin) in the macrophages of the spleen.
Unconjugated bilirubin is not soluble in water and is bound to albumin and sent to the liver for conjugation.
Conjugated bilirubin (direct bilirubin) is soluble in water and is excreted into the bile and eventually into the small intestine.

Functions of Bilirubin

Bilirubin is measured in neonates to assess the severity of neonatal jaundice.
Bilirubin levels are also measured to assess liver disease, bile duct blockage, or hemolytic anemia.
Normal bilirubin levels in adults are 0.2-1.2 mg/dl (total bilirubin) and 0.0-0.2 mg/dl (direct bilirubin).
In neonates, bilirubin levels less than or equal to 8 mg/dl are considered normal.

Jaundice

Jaundice is a yellowish discoloration of the skin, conjunctival membranes, and other mucous membranes caused by hyperbilirubinemia (increased levels of bilirubin in the blood).
Jaundice is classified into three categories: pre-hepatic, hepatic, and post-hepatic, depending on the location of the pathology affecting the physiological mechanism.

Gamma Glutamyl Transferase (ɣ-GT)

ɣ-GT is elevated in about 75% of chronic drinkers, and the level is correlated with the duration of alcohol intake or dose.
ɣ-GT is also elevated in hepatic malignancies, toxic hepatitis, and biliary disease.
ɣ-GT is moderately elevated in acute pancreatitis and pancreatic malignancy associated with hepatobiliary obstruction.

Description

This quiz covers the functions of albumin in transporting substances through blood, causes of hypoalbuminemia, and its relation to liver disease. Learn about the role of albumin in the body and its clinical implications.