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Glucose Tolerance, serum or plasma (087-0040)
Test Mnemonic:


Specimen Requirements:
Test Included:

Serum or plasma glucose and urine glucose




Serum separator tube (SST) (Preferred), Plasma separator tube (PST), red stopped vacutainer tube or gray-topped (sodium fluoride) tube for blood sample and plastic container for urine aliquot.

Minimum Volume:

3 mL of blood


Delivered to Sample Management within 2 hours of collection.  

Specimen Preparation:

Allow specimen to clot completely at room temperature. Centrifuge to separate serum from cells within 2 hours of collection. Transfer serum from red-topped or gray-topped tube to labeled plastic transport tube. 


For serum and plasma: Room temperature for ≤24 hours, Refrigerated for ≤7 days, Frozen for ≤1 year. For urine: Refrigerated   Not determined.

Causes for Rejection:

Incomplete and/or incorrect sample identification, improper storage/transport, gross hemolysis, icterus or lipemia

Reference Range:

By report (reports may vary based on instrumentation, patient age and sex)

Turnaround Time:

Routine: 8 hours; ASAP: 4 hours; STAT: 1 hour.


 End Point Colorimetric, oxidase  


24 hours a day; 7 days a week


Clinical Chemistry

CPT 4 Code:



All specimens must have collection time on tube and urine container (e.g., 1/2 hr, 1 hr, 2 hr, 3 hr, etc.). Write times of collection for each sample on the request form.

When ordering tests for which Medicare or Medicaid reimbursement will be sought, physicians should only order tests that are medically necessary for the diagnosis or treatment of the patient. Components of the organ or disease panels may be ordered individually. The diagnostic information must substantiate all tests ordered and must be in the form of an ICD-10 code or its verbal equivalent.
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