A small amount of blood may be
taken and tested to check one or more of the following:
Alpha fetoprotein (AFP). This is normally high in
newborns. But high levels in the blood of an older child can be a sign of liver
Albumin. This is a protein made by the liver. It can
be measured with a blood test. When a person has liver disease, the level of
albumin in the blood (serum albumin) is often low.
Alkaline phosphatase (AP). This is an enzyme made in
the liver and bone. It’s measured with a blood test. A high level may mean there’s
a problem with the bile ducts in the liver.
Alanine aminotransferase (ALT). This is an enzyme made
by the liver. When the liver is damaged, ALT leaks into the blood. If a blood test
finds a high level of ALT, this can be a sign of liver problems such as
inflammation, scarring, or a tumor.
Ammonia. This is a harmful substance left behind in
the blood after digestion. Normally, the liver removes ammonia from the blood and
turns it into urea, which leaves the body with urine. If a blood test shows that
the ammonia level is too high, this process isn’t happening as it should.
Aspartate aminotransferase (AST). This is another
enzyme made by the liver. High levels suggest liver injury, especially if the ALT
level is also high.
Bilirubin. This is a yellow substance made when the
body breaks down red blood cells. It’s collected by the liver to be sent out of
the body with stool. When something is wrong with the liver or bile ducts,
bilirubin may build up in the body. This causes yellowing of the skin and the
whites of the eyes (jaundice). Two measurements may be taken: total bilirubin and
direct bilirubin. A high total bilirubin level means the liver isn’t breaking down
bilirubin. A high direct bilirubin level suggests a blockage in the bile
Complete blood count (CBC). This is a test that
measures all the parts of the blood: red blood cells, white blood cells, and
platelets. Problems with these counts can mean infection or illness. They can also
be a sign of a problem with the spleen. This is an organ close to the liver that
can be affected by liver disease.
Essential fatty acids (EFAs). These are important
nutrients. EFA levels may be lower when the liver is diseased. This is because the
liver can’t absorb and transport EFAs as it should.
Gamma-glutamyl transpeptidase (GGT). This is an enzyme
that’s often measured along with other enzymes to gauge liver problems. GGT is
measured with a blood test. If AP and GGT are both high, this is a sign that the
bile ducts in the liver may be diseased or blocked.
Glucose. This is sugar in the blood. A healthy liver
helps the body keep a normal glucose level. If a blood test reveals that glucose
is low, this may mean the liver is not working properly.
Prothrombin time (PT). This tests the ability
of the blood to clot. The liver makes a protein that helps with clotting, so
problems with clotting can be a sign of liver disease. Part of this blood test is
the international normalized ratio (INR). This measures clotting factors made from
Serum bile acid (SBA). This is the amount of
bile acid in the blood. A high level may mean that bile ducts are blocked.
Vitamins A, D, E, and K. These are fat-soluble
vitamins that are absorbed by the liver, with help from bile. If a blood test
shows that levels of these vitamins are low, this could mean your child’s liver is
not absorbing them properly.
Zinc. This is a nutrient that is absorbed by the
liver. If a blood test shows that your child’s zinc level is low, this could mean
the liver isn’t absorbing zinc properly.