Liver cirrhosis can be the result of certain viral infections (such as the hepatitis viruses) or due to the ingestion of toxins (including large amounts of alcohol). When the liver becomes heavily damaged, it can stop making certain proteins, including the blood protein albumin. As a result, the levels of albumin and other proteins can be measured to diagnose liver cirrhosis.
Cirrhosis and Albumin
One of the functions of the liver is to produce a protein called albumin. Patients with liver cirrhosis have developed permanent damage to their liver, causing portions of the liver to be replaced with scar tissue. When this happens, the liver's ability to produce proteins (such as albumin) becomes impaired.
Medline notes that albumin has two important roles in the blood. Albumin helps transport other molecules such as bilirubin, some medications, progesterone and calcium through the blood. Albumin is also important for maintaining the amount of liquid in the blood via its effect on oncotic pressure. Oncotic pressure is the tendency of water to flow to areas where there are large amounts of dissolved substances. By being dissolved in the blood, albumin is able to help keep water from leaving the bloodstream.
Serum albumin is a commonly ordered blood test that can be used to check for liver disease and other medical conditions. LabTests Online explains that this test involves taking a blood sample from the patient's blood. The blood sample is then sent to a lab, which measures the levels of albumin, typically in terms of grams (g) of albumin per deciliter (dl) of blood. Medline notes that the normal range of serum albumin is between 3.4 and 5.4g/dl.
Causes of Low Albumin
There are a variety of different diseases aside from liver cirrhosis that can cause serum albumin levels to be low. One is inflammation of the kidneys (glomerulonephritis), which causes albumin to seep out into the urine. Massive burns can also lead to albumin loss. Malnutrition or problems with protein absorption can also lead to low serum albumin levels because the body is unable to absorb enough protein to make sufficient quantities of albumin. RnCeus explains that liver disease causes a significant drop in serum albumin levels only if the condition is chronic and the liver is severely damaged.
Liver Function Tests
Patients with low albumin levels will commonly receive other tests to determine if liver disease is the cause of the abnormal albumin levels. The Mayo Clinic explains that the levels of certain liver enzymes, including alanine and aspartate transaminase (often abbreviated as ALT and AST) as well as alkaline phosphatase (ALP) may be measured; high levels of these enzymes indicate liver damage. Levels of builirubin, which is a protein normally processed and excreted by the liver, may also be measured.