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2 HOUR NON-GESTATIONAL ORAL GLUCOSE TOLERANCE TEST (OGTT)

Message
A total of 2 specimens will be drawn.
  • Draw fasting specimen
  • Administer 75g oral glucose (Glucola) or dose specified by physician
  • Draw specimen 2 hours after consumption of oral glucose (Glucola)


Test Code
2HNGT


Alias/See Also
GTT


CPT Codes
82947, 82950

Includes
  • Baseline (glucose) fasting
  • 2 hour glucose (post 75g dose)


Preferred Specimen
1 Gold tube (gel separator)


Minimum Volume
0.5 mL


Other Acceptable Specimens
1 Lavender tube (EDTA) or
1 Green tube (Lithium Heparin) or
1 Gray tube (Sodium Fluoride)


Instructions
Separate serum or plasma from red cells rapidly to minimize the loss of glucose through glycolysis. Refrigerate until tested.


Transport Temperature
Refrigerate


Specimen Stability
  • 2-8°C up to 3 days
  • 15-30°C up to 24 hours (plasma)
  • 15-30°C up to 8 hours (serum)


Reject Criteria (Eg, hemolysis? Lipemia? Thaw/Other?)
Hemolyzed


Methodology
Hexokinase

Setup Schedule
M. Tu, W, Th, F, Sa, Su


Report Available
Within 24 hours of receipt at the performing laboratory.


Reference Range
Test Result (mg/dL)
Fasting Glucose 70-99
2 Hour Glucose 70-139


Clinical Significance
This is the one-step glucose tolerance test recommended by the American Diabetes Associaion (ADA) used to establish the diagnosis of diabetes mellitus in males, non-pregnant females, and children.


Performed By
Alverno Laboratories

Performing Laboratory
Alverno Central Lab  
NCHB1 (Chemistry, Beckman AU)


Last Updated: June 8, 2023


The CPT Codes provided in this document are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payor being billed. Any Profile/panel component may be ordered separately. Reflex tests are performed at an additional charge.