This article explains the purpose of liver function tests and their limitations.
The tests can also be helpful when the following needs or circumstances arise.
Sometimes, appearances can be deceiving.
Verywell / Emily Roberts
“However, the college stops short of saying what constitutes a toxic intake.
Certain lifestyle factors can play into the risk of liver injury as well.
Heavy alcohol intake increases the risk ofalcoholic liver disease, andIV drug use increases the risk of infectious hepatitis.
LFTs often reflect changes in liver function that must be monitored over time.
There are some limitations of liver function tests.
Changes in your LFT values may lag behind your liver disease as well.
Before
You may have your blood drawn at your healthcare provider’s office.
If not, you may be sent to a lab or hospital to have it done.
You may need to abstain from food and drink for six to eight hours before your blood test.
You may also have to stop certain medications in advance of the test.
Who’s Paying?
Most insurance companies cover liver function tests.
Check with your insurer ahead of time so don’t have a surprise expense.
The test itself should take only a few minutes.
You’ll be asked to expose your arm above the elbow and make a fist.
A tourniquet will then be tied around your arm, above your elbow.
The skin on the inner surface of your arm will be cleaned and the needle inserted into a vein.
You may feel a mildly sharp sensation when the needle is inserted or it might not hurt at all.
Your blood will be collected in a tube.
After this, you should be free to leave.
If you’ve been fasting, it’s a good idea to eat or drink something right away.
Do not attempt to treat these issues on your own.
The individual test results are typically used together, not individually, to diagnose a liver problem.
So for example, if one number is slightly elevated, it likely won’t be cause for concern.
It’s when several results are abnormal that a problem may be suspected.
The same goes for anything that decreases the flow of oxygen or blood to the liver.
A low level of albumin can also be because of poor nutrition or chronic illness.
Various diseases can cause elevations in ALP, including those that damage or obstruct these ducts.
A normal level of ALP is 44 to 147 units/liter.
Bilirubin
Bilirubin is made as your body breaks down red blood cells.
High levels can point to a health condition such as anemia, jaundice, or liver disease.
A total bilirubin (T. Bili) test measures the total amount of bilirubin in the blood.
Liver dysfunction results in a buildup of bilirubin in the blood.
However, total bilirubin levels may be elevated before jaundice becomes visibly apparent.
A normal level is 0.2 to 1.9 mg/100 ml.
GGT can be elevated in early liver disease, making it a highly sensitive marker.
Generally, the test is used to confirm that an elevated ALP is due to this cause.
But it is not specific.
It can also be elevated after heavy alcohol use.
A normal level is 8 to 61 units/liter for males and 5 to 36 units/liter for females.
If your LFTs are not normal, you may need additional blood tests to determine the reason why.
You may also need to have imaging tests so that your healthcare provider can visualize your liver.
If results suggest the possibility of a cancer, you may need aliver biopsyor other testing.
You may also need follow-up LFTs at some point.
If you have had bile duct obstruction, you may need interventional treatment or surgery.
And you should expect to have the tests repeated within a few weeks to monitor your liver function.
With a severe systemic disease, you may need your liver enzymes checked regularly.
From many vantage points, the tests can be very helpful.
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