Specimen:
Collect
- One Gray Top (1HR)
- One Gray Top (2HR)
- One Gray Top (FAST)
Also Acceptable:
- One SST (1HR)
- One SST (2HR)
- One SST (FAST)
Submit
- Three 4 mL (Min:1 mL) Whole blood in Gray Top. Submit Refrigerated.
Also Acceptable:
- Three 1 mL (Min:0.5 mL) Plasma . Submit Refrigerated. Submit in a Standard Transport Tube.
- Three 1 mL (Min:0.5 mL) Serum in SST. Submit Refrigerated.
Special Handling
- ADA Recommends:
1. Perform at 24-28 weeks gestation in women not previously diagnosed with overt diabetes.
2. The GTT should be performed in the morning after an overnight fast of at least 8 hours.
3. Draw fasting specimen, then give 75gm glucola. At 1 hour draw "1 HR" post sample. At 2 hour draw "2 HR" post sample. Label tubes "Fasting", "1 HR", and "2 HR".
Other alternative samples:
Green Top (Li Hep), Lavender EDTA, Pink EDTA, Red Top.
If using alternative serum or plasma separate from cells ASAP.
Serum or plasma stability: Ambient 8 hrs, RF 3 days, FZ 1 month
Rejection Criteria
- Hemolyzed specimens
- Microbially Contaminated
- Unlabled Specimens
Stability
Ambient: 1 Day(s); Refrigerated: 3 Day(s); Frozen: Unacceptable; Incubated: Unacceptable
Methodology
- Colorimetric
- Kinetic
Performed
Mon-Fri
Reported
1-3 Day(s)
CPT Codes
- 82951
Interpretive Data
Please see report for interpretive data.
Components
- 2400 - GLUCOSE, FASTING
- 2401 - GLUCOSE, 1HR
- 2402 - GLUCOSE, 2HR
Last Updated: October 26, 2024 @ 9:13 am
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