Albumin is a type of protein found in large amounts in the blood. In fact, it is the most abundant protein in blood serum and usually accounts for between 50% and 60% of all serum proteins.
Most of the serum albumin is synthesized in the liver and performs several functions, mainly transporting hormones, fatty acids and many other substances such as calcium or drugs. It also acts on the buffer system to control blood pH and maintain oncotic pressure.
The concentration of protein in the blood is called proteinemia, and it can be normal, high (hyperproteinemia), or low (hypoproteinemia). The concentration of albumin in the blood would be albuminemia, a specific type of proteinemia. The normal ranges of albuminemia are:normal albuminemia: 3.5 – 5.0 g/dL (or 35 – 50 g/L). Hypoalbuminemia: concentration below 3.5 g/dL. hyperalbuminemia: above 5.0 g/dL.
Hypoalbuminemia is defined as a blood albumin concentration below normal (below 3.5 g/dL). It is indicative of a failure or abnormal functioning of the liver, such as cirrhosis or chronic hepatitis. Albumin measurement is a standard test in any assessment of liver function.
Hypoalbuminemia can also occur when there are kidney problems that increase proteinuria (protein in the urine), such as nephrotic syndrome, or due to malnutrition problems.
One of the main symptoms of hypoalbuminemia is edema, since albumin is the protein that contributes most to the oncotic pressure that regulates the outflow of fluid from the bloodstream to the tissues.
Other possible symptoms include fatigue, cramping, muscle weakness and lack of appetite. Hypoalbuminemia is also one of the main mechanisms leading to ascites (accumulation of fluid in the peritoneal cavity).
Most common causes of hypoalbuminemia:liver diseases: cirrhosis, hepatitis. Excessive excretion in urine: renal failure, nephrotic syndrome, diabetic nephropathy, etc. Excessive protein loss or lack of absorption in the intestine: e.g. Menetrier disease, inflammatory bowel disease, etc. Cardiovascular diseases: congestive heart failure, pericarditis, etc. Severe burns (plasma is lost due to the absence of the skin barrier). malnutrition In some cases, hypoalbuminemia may occur due to hemodilution during pregnancy or in situations that increase vascular permeability or decrease lymph drainage. some cancers: eg sarcoma Genetic analbuminemia (very rare disease) amyloidosis Chemotherapy
Hyperalbuminemia appears when the albumin concentration is above the normal range, generally considered to be above 5.0 g/dL. The most frequent cause is dehydration, both acute and chronic.
Hyperalbuminemia is also associated with high protein diets and some infectious diseases, eg various bacterial meningitis.