QuestionI had a glucose test done for insurance. The results came back as "invalid due to Glycolysis". What does this mean?
AnswerHi,
Please be aware that the information provided is not a substitute for medical advice and should not be interpreted as medical advice. This information is being provided for informational purposes only. Your own physician is the best resource to interpret your specific laboratory results and should be consulted for medical advice regarding your own specific health condition.
Without knowing the other lab result values, it's difficult to say what these results mean in your situation. What lab testing was run? A comprehensive metabolic panel? Were your other values normal or..? If not, what were the other values?
Glycolysis is a biochemical process in which glucose is converted to ATP (Adenosine Tri Phosphate) at the cellular level and the ATP generated from this process is used as an energy source for most living organisms including humans. The glycolysis process itself converts glucose to pyruvic acid and involves a series of biochemical reactions with each biochemical reaction catalyzed in a specific sequence by a specific enzyme. Below is additional information on the glycolysis process.
http://www.answers.com/topic/glycolysis
If your other lab results were normal, it could be a specimen handling/acceptability problem and if so the specimen will need to be redrawn and retested.
To understand what the results in this case can mean, it is helpful to understand the entire laboratory test ordering, specimen collection, and testing process.
A physician orders specific laboratory tests or a series of related tests called a panel based on a clinical exam, or in your case, the insurance company is requesting that specific laboratory tests be ordered for further evaluation to assess insurability based on testing results, probably in this case as a screen for Diabetes mellitus.
A nurse or other healthcare professional collects the specimen
Hospital Clinical laboratory protocol requires that very strict specimen acceptability requirements be followed by the Clinical Laboratory Scientist responsible for accepting or rejecting the specimen for the purpose of specific laboratory testing ordered by the physician. A CLS must reject a specimen (i.e., urine, blood, cerebrospinal fluid, etc.) if it does not meet these very strict and very specific specimen acceptability requirements. The specific specimen acceptability requirements vary depending on the specimen itself and the lab test to be performed on it as ordered by the physician. For example, the specimen acceptability requirements can involve specific temperature requirements, being collected in specific containers, and minimum volumes for testing requirements. If the specimen does not appear to meet the specific specimen acceptability requirements for the specific test or tests ordered, the CLS is required to reject the specimen and request a redraw or recollection of the specimen.
For a serum glucose, the blood specimen should be collected ideally in an SST or PST vacutainer tube with a gel separator with flouride added to inhibit glycolysis, and then spun down in a centrifuge to separate the serum or plasma (liquid part of the blood) from the blood cells so that the serum or plasma can be tested. If the blood specimen is collected in a non-gel separator tube, the glucose in the specimen continues to be metabolized at a rate of 10%/hour by the blood cells in the specimen resulting in an inaccurately low glucose result value.
Below is an example of SST and PST tubes used to collect blood specimens for glucose testing
A PST tube has a green top and contains the anticoagulant Lithium heparin and a gel for plasma separation.
An SST tube has a gold or red/grey top and contains spray coated silica and a polymer gel for serum separation
http://www.atlanticmedsupply.com/shopdisplayproducts.asp?id=148&cat=Vacutainer+T...
Below is an example of specimen acceptability requirements for glucose testing
http://www.mayomedicallaboratories.com/test-catalog/print.php?unit_code=89115
Cautions
Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances. Once the blood is drawn, the cells in the blood begin to metabolize the
glucose that is present in the specimen. At room temperature, the glucose
concentration in the blood will decrease by 10% per hour. Therefore, in a
non-gel separator tube, the specimen should be centrifuged as soon as
possible and the plasma or serum removed from the cells. If the blood is
drawn in a SST or PST, the glucose is stable once the sample has been
spun and the gel is in place. Inhibitors of glucose metabolism such as
fluoride also can be used. In these tubes, glycolysis will take place, but at
a much reduced rate (approximately 10% over 3 hours).
http://www.ehow.com/about_5505365_invalid-blood-results-due-glycolysis.html
Again, without knowing the other lab values, it is difficult to say what the results mean but if, for example, the blood specimen was not collected in an SST or PST tube and/or was allowed to sit a number of hours before being spun down and/or tested, the results may be invalid due to improper specimen handling and the specimen may need to be redrawn and retested.
