This is a blood test to measure the amount of the enzyme aldolase.

Blood is drawn from a vein on the inside of the elbow or the back of the hand. The puncture site is cleaned with antiseptic, and an elastic band is placed around the upper arm to apply pressure and restrict blood flow through the vein. This causes veins below the band to fill with blood.

A needle is inserted into the vein, and the blood is collected in an air-tight vial or a syringe. During the procedure, the band is removed to restore circulation. Once the blood has been collected, the needle is removed, and the puncture site is covered to stop any bleeding.

For an infant or young child:

The area is cleansed with antiseptic and punctured with a sharp needle or a lancet. The blood may be collected in a pipette (small glass tube), on a slide, onto a test strip, or into a small container. Cotton or a bandage may be applied to the puncture site if there is any continued bleeding.

Fasting may be required up to 6 hours before the test. Some drugs may interfere with this test. Make sure that your doctor is aware of all drugs you are taking, both prescription and nonprescription.

When the needle is inserted to draw blood, some people feel moderate pain, while others feel only a prick or stinging sensation. Afterward, there may be some throbbing.

This test is an indicator of muscle damage.

Aldolase is an enzyme that is involved in the breakdown of glucose, fructose, and galactose, a process used by cells to generate energy in the form of ATP (adenosine triphosphate). Aldolase is in particularly high concentration in muscle.

A typical reference range is 1.0 to 7.5 U/L. There are slight differences between men and women. The testing laboratory should be consulted for normal values of their test.

Note: U/L = units per liter

Greater-than-normal levels of aldolase may indicate:

• damage to skeletal muscles
• hepatitis
• infectious mononucleosis
• liver, pancreatic, or prostate cancer
• muscular dystrophy
• myocardial infarction
• polymyositis

• dermatomyositis

The risks associated with having blood drawn are:

• excessive bleeding
• fainting or feeling lightheaded
• hematoma (blood accumulating under the skin)
• infection (a slight risk any time the skin is broken)
• multiple punctures to locate veins

Veins and arteries vary in size from one patient to another and from one side of the body to the other. Obtaining a blood sample from some people may be more difficult than from others.