Myoglobin is a protein found in heart tissue and other muscles. It is released into the blood after damage to the heart or other muscles. Damage can occur from a serious event such as a heart attack or a burn.
Myoglobin can be checked with a blood test or a urine test. Levels in the blood will increase within about 3 hours after the damage. Myoglobin can be found in urine for several days.
Why It Is Done
The myoglobin test is used to look for disease or injury of muscle tissue. The urine test can help check for rhabdomyolysis.
How To Prepare
Be sure to tell your doctor about all the medicines you take, even over-the-counter ones.
You may be asked to sign a consent form.
Talk to your doctor about any concerns you have regarding the need for the test, its risks, how it will be done, or what the results will mean. To help you understand the importance of this test, fill out the medical test information form .
How It Is Done
The health professional taking a sample of your blood will:
- Wrap an elastic band around your upper arm to stop the flow of blood. This makes the veins below the band larger so it is easier to put a needle into the vein.
- Clean the needle site with alcohol.
- Put the needle into the vein. More than one needle stick may be needed.
- Attach a tube to the needle to fill it with blood.
- Remove the band from your arm when enough blood is collected.
- Put a gauze pad or cotton ball over the needle site as the needle is removed.
- Put pressure on the site and then put on a bandage
- Wash your hands to make sure they are clean before you collect the urine.
- If the collection cup has a lid, remove it carefully. Set it down with the inner surface up. Do not touch the inside of the cup with your fingers.
- Clean the area around your genitals.
- For men: Pull back the foreskin, if you have one. Clean the head of the penis thoroughly with medicated towelettes or swabs.
- For women: Spread open the folds of skin around the vagina with one hand. Then use your other hand to clean the area around the vagina and urethra thoroughly with medicated towelettes or swabs. Wipe the area from front to back to avoid spreading bacteria from the anus to the urethra.
- Start urinating into the toilet or urinal. Women should keep holding apart the folds of skin around the vagina while they urinate.
- After the urine has flowed for several seconds, place the collection cup into the stream. Collect about 60 mL (2 fl oz) of this "midstream" urine without stopping the flow.
- Do not touch the rim of the cup to your genital area. And don't get toilet paper, pubic hair, stool (feces), menstrual blood, or other foreign matter in the urine sample.
- Finish urinating into the toilet or urinal.
- Carefully replace the lid on the cup. Return the cup to the lab. If you are collecting the urine at home and can't get it to the lab in an hour, refrigerate it.
How It Feels
The blood sample is taken from a vein in your arm. An elastic band is wrapped around your upper arm. It may feel tight. You may feel nothing at all from the needle, or you may feel a quick sting or pinch.
It is not painful to collect a urine sample.
There is very little chance of a problem from having a blood sample taken from a vein.
- You may get a small bruise at the site. You can lower the chance of bruising by keeping pressure on the site for several minutes.
- In rare cases, the vein may become swollen after the blood sample is taken. This problem is called phlebitis. You can use a warm compress several times a day to treat this.
Collecting a urine sample does not cause problems.
Myoglobin is a protein found in muscles. It can be checked with a blood test or a urine test.
These numbers are just a guide. The range for "normal" varies from lab to lab. Your lab may have a different range. Your lab report should show what range your lab uses for "normal." Also, your doctor will evaluate your results based on your health and other factors. So a number that is outside the normal range here may still be normal for you.
Normal in blood:
5–70 ng/mL or 5–70 mcg/L
Normal in urine:
Negative or <20
What Affects the Test
You may not be able to have the test, or the results may not be helpful, if:
- You recently got a shot (injection) in a muscle.
- You recently did vigorous exercise.
- You recently had an injury to another muscle.
- You use heavy amounts of alcohol or certain drugs.
What To Think About
Other tests may be done along with your myoglobin test. Creatine kinase, lactic dehydrogenase, and troponin may also be tested. They can also show if there is damage to muscle tissue.
Current as of: December 9, 2019
Author: Healthwise Staff
Medical Review: Kathleen Romito, MD - Family Medicine
Brian O'Brien, MD, FRCPC - Internal Medicine
E. Gregory Thompson, MD - Internal Medicine
Adam Husney, MD - Family Medicine
Martin J. Gabica, MD - Family Medicine
Current as of: December 9, 2019