What are other Names for this Test? (Equivalent Terms)
- Serum Creatine Test
What is the Creatine Blood Test? (Background Information)
- Creatine is a molecule used by muscles as a quick source of energy. Creatine is made in the liver. It is then converted to creatine phosphate and stored by muscles for use as energy
- Muscles use creatine after initial stores of its main energy compound, adenosine triphosphate (ATP) is depleted. This occurs within several seconds of a physical activity
- Creatine provides energy for roughly 30 minutes of muscle activity. Anaerobic metabolism then takes over, followed by aerobic metabolism 90 minutes after the onset of muscle activity
- Creatine is broken down into creatinine. Creatinine enters the bloodstream and gets excreted via the kidneys
- The Creatine Blood Test is used to determine the levels of creatine in blood. It may be used to diagnose muscle disorders. However, this test is only rarely performed
What are the Clinical Indications for performing the Creatine Blood Test?
Following are the clinical indications for performing the Creatine Blood Test:
- Muscle weakness and pain
- Drooping eyelids
- Abnormal vision
- Abnormal facial expressions
- Difficulty swallowing
- Difficulty chewing
How is the Specimen Collected for the Creatine Blood Test?
Following is the specimen collection process for Creatine Blood Test:
Sample required: Blood
Process of obtaining blood sample in adults:
- A band is wrapped around the arm, 3-4 inches above the collection site (superficial vein that lies within the elbow pit)
- The site is cleaned with 70% alcohol in an outward spiral, away from the zone of needle insertion
- The needle cap is removed and is held in line with the vein, pulling the skin tight
- With a small and quick thrust, the vein is penetrated using the needle
- The required amount of blood sample is collected by pulling the plunger of the syringe out slowly
- The wrap band is removed, gauze is placed on the collection site, and the needle is removed
- The blood is immediately transferred into the blood container, which has the appropriate preservative/clot activator/anti-coagulant
- The syringe and the needle are disposed into the appropriate “sharp container” for safe and hygienic disposal
Preparation required: No special preparation is needed prior to the test.
What is the Significance of the Creatine Blood Test Result?
A high value (greater than 0.7 mg/dL for men and 0.9 mg/dL for women) for the Creatine Blood Test may indicate:
- Muscle destruction
- Amyotrophic lateral sclerosis (ALS)
- Myasthenia gravis
- Muscular dystrophies
The laboratory test results are NOT to be interpreted as results of a "stand-alone" test. The test results have to be interpreted after correlating with suitable clinical findings and additional supplemental tests/information. Your healthcare providers will explain the meaning of your tests results, based on the overall clinical scenario.
Additional and Relevant Useful Information:
- Certain factors may interfere with the results of the Creatine Blood Test. These include diet and exercise
Certain medications that you may be currently taking may influence the outcome of the test. Hence, it is important to inform your healthcare provider of the complete list of medications (including any herbal supplements) you are currently taking. This will help the healthcare provider interpret your test results more accurately and avoid unnecessary chances of a misdiagnosis.
The following DoveMed website links are useful resources for additional information:
Please visit our Laboratory Procedures Center for more physician-approved health information: