Glucose in Human Serum with Roche c502
Detection of Glucose in Human Serum with Roche c502
|Test Name:||In vitro test for the quantitative determination of glucose in human serum and plasma on Roche/Hitachi cobas c systems.|
|Method Name:||The UV test measures the oxidation of glucose-6-phosphate in the presence of NADP. The rate of NADPH formation during the reaction is directly proportional to the glucose concentration and is measured photometrically.|
|Results:||Technical Range: 2-750 mg/dL
Reportable Range: 2.8-692.3 mg/dL
|Reference Ranges:||0-11 months: not established
≥1 year: 70-140 mg/dL
Interpretation Any of the following results, confirmed on a subsequent day, can be considered diagnostic for diabetes:
-Fasting plasma or serum glucose ≥126 mg/dL after an 8-hour fast
-2-Hour plasma or serum glucose ≥200 mg/ dL during a 75-gram oral glucose tolerance test (OGTT)
-Random glucose >200 mg/dL, plus typical symptoms
Patients with “impaired” glucose regulation are those whose fasting serum or plasma glucose fall between 101 and 126 mg/dL, or whose 2-hour value on oral glucose tolerance test fall between 140 and 199 mg/dL. These patients have a markedly increased risk of developing type 2 diabetes and should be counseled for lifestyle changes and followed up with more testing. Indications for screening and testing include strong family history, marked obesity, history of babies over 9 pounds, and recurrent skin and genitourinary infections.
Glucose levels of 25 mg/dL or lower in infants younger than 1 week are considered to be potentially life threatening, as are glucose levels of 40 mg/dL or lower in infants older than 1 week. Glucose levels of 400 mg/dL and higher are considered a critical value.
|Clinical Significance:||Glucose is the major carbohydrate present in the peripheral blood. Oxidation of glucose is the major source of cellular energy in the body. Glucose derived from dietary sources is converted to glycogen for storage in the liver or to fatty acids for storage in adipose tissue. The concentration of glucose in blood is controlled within narrow limits by many hormones, the most important of which are produced by the pancreas. The most frequent cause of hyperglycemia is diabetes mellitus resulting from a deficiency in insulin secretion or action. A number of secondary factors also contribute to elevated blood glucose levels. These include pancreatitis, thyroid dysfunction, renal failure, and liver disease. Hypoglycemia is less frequently observed. A variety of conditions may cause low blood glucose levels such as insulinoma, hypopituitarism or insulin induced hypoglycemia.|
|Submission Criteria:||For specimen collection and preparation, only use suitable tubes or collection containers.
Only the specimens listed below were tested and found acceptable.
Plasma: Li-heparin and K2-EDTA, NaF/Na2EDTA, KF/Na2EDTA NaF/K-Oxalate plasma.
The stability of glucose in specimens is affected by storage temperature, bacterial contamination, and glycolysis. Plasma or serum samples without preservative (NaF) should be separated from the cells or clot within half an hour of being drawn. When blood is drawn and permitted to clot and to stand uncentrifuged at room temperature, the average decrease in serum glucose is ~7 % in 1 hour (5 to 10 mg/dL). This decrease is the result of glycolysis.
The sample types listed were tested with a selection of sample collection tubes that were commercially available at the time of testing, therefore not all available tubes of all manufacturers were tested. Sample collection systems from various manufacturers may contain differing materials which could affect the test results in some cases. When processing samples in primary tubes (sample collection systems), follow the instructions of the tube manufacturer.
Storage and Stability: 3 days at 4°C
|Rejection Criteria:||Rejection criteria include but are not limited to:
1. Specimens containing fibrin or clots.
2. Excessive platelet clumping
3. Leaking specimens
4. Substandard mixing or collection
5. Expired or improperly stored collection tubes.
6. Improperly filled tubes based on collection tube manufacturer’s guidelines.
7. Contaminated specimens (IV fluid, foreign particles, etc.)
8. Specimens not analyzed within the appropriate time frame.
9. Samples not shipped at appropriate temperature.
10. Samples without 2 proper identifiers or samples having identifiers that do not match the electronic or paper lab requisition.
|Authorization:||Diagnostic testing can only be performed with approval from an authorized provider/agency.|
|Turn Around Time:||1 day.|