100 gram, fasting, 3-hour gestational glucose tolerance confirmation
Test Mnemonic
GTGST3
CPT Codes
- 82951 - QTY (1)
- 82952 - QTY (1)
Includes
- Glucose, Fasting
- Glucose, 1 hr
- Glucose 2 hr
- Glucose 3 hr
Performing Laboratory
Cleveland Clinic Laboratories
Specimen Requirements
| Volume | Type | Container | Collect Temperature | Transport Temperature | Special Instructions |
|---|---|---|---|---|---|
| 1 mL | Plasma | Potassium oxalate/sodium fluoride (Gray) | Centrifuge and refrigerate. | Aliquot into CCL aliquot tube |
Minimum Specimen Requirements
| Volume | Type | Container | Collect Temperature | Transport Temperature | Special Instructions |
|---|---|---|---|---|---|
| 0.3 mL |
Stability
| Environmental Condition | Description |
|---|---|
| Ambient | 24 hours |
| Refrigerated | After removed from cells: 72 hours |
| Frozen | Unacceptable |
Days Performed
Sun - Sat
Turnaround Time
8 hours
Methodology
| Name | Description |
|---|---|
| Glucose Hexokinase |
Reference Range
| Glucose GST, 1 Hr | |||||
|---|---|---|---|---|---|
| Sex | Age From | Age To | Type | Range | Range Unit |
| Normal | 74-179 | mg/dL | Years | 99 Years | Urgent | >500 | mg/dL | Urgent | Inpatient only: 40-49 mg/dL (First result only, once every 24 hours.) | mg/dL | Years | 99 Years | Critical | <40 | mg/dL |
| Glucose GST, 2 Hr | |||||
| Sex | Age From | Age To | Type | Range | Range Unit |
| Normal | 74-154 | mg/dL | Years | 99 Years | Urgent | >500 | mg/dL | Urgent | Inpatient only: 40-49 mg/dL (First result only, once every 24 hours.) | mg/dL | Years | 99 Years | Critical | <40 | mg/dL |
| Glucose GST, 3 Hr | |||||
| Sex | Age From | Age To | Type | Range | Range Unit |
| Normal | 74-139 | mg/dL | Years | 99 Years | Urgent | >500 | mg/dL | Urgent | Inpatient only: 40-49 mg/dL (First result only, once every 24 hours.) | mg/dL | Years | 99 Years | Critical | <40 | mg/dL |
| Glucose GST, Fasting | |||||
| Sex | Age From | Age To | Type | Range | Range Unit |
| Normal | 74-94 | mg/dL | Years | 99 Years | Urgent | >500 | mg/dL | Urgent | Inpatient only: 40-49 mg/dL (First result only, once every 24 hours.) | mg/dL | Years | 99 Years | Critical | <40 | mg/dL |
Special Info
Patient should be fasting at least 8 hours prior to test. Collect a fasting specimen, then administer 100 gm of Dextrose within 5 minutes. Collect specimens at 1, 2 and 3 hours post glucose load. Indicate collection time on each specimen.
Clinical Info
Confirmation of Gestational Diabetes Mellitus American Congress of Obstetricians and Gynecologists (Carpenter/Coustan) guidelines state gestational diabetes mellitus is present when 2 or more of the plasma glucose concentrations meet or exceed the following levels: fasting: 95 mg/dL; 1 hr: 180 mg/dL; 2 hr: 155 mg/dL; and 3 hr: 140 mg/dL.