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Glucose Tolerance Test, Non-pregnant
| Item | Value | ||||||
|---|---|---|---|---|---|---|---|
| Approval req'd? | No | ||||||
| Available Stat? | No | ||||||
| Utilization Guidelines | THIS TEST IS NO LONGER RECOMMENDED FOR ROUTINE USE. See Additional Information. |
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| Test code | OGT2 | ||||||
| Test group | Glucose | ||||||
| Performed by | Parnassus & Mt. Zion Chemistry | ||||||
| In House Availability | Test available 24 hours per day 7 days per week | ||||||
| Method | Oxygen consumption (O2 electrode with glucose oxidase) | ||||||
| Patient Preparation | The patient should be instructed by the care-giver to eat a normal diet containing at least 150 g of carbohydrate and carry out normal physical activity for at least 3 days prior to the morning of the test. An 8-14 hour fast is required before initial baseline sample collection. | ||||||
| Collection Instructions | For outpatients, PLEASE SCHEDULE IN ADVANCE with the ACC outpatient lab, 415-353-2736, or Post St. lab, 415-885-7531. Outpatient testing at ACC available 0730-1530 weekdays, and at 2330 Post St. 0800-1400 weekdays. The patient should be seated for the test and should not smoke. A gray top tube should be used. For patients < 18 years of age, obtain the patient's weight and give the patient 1.75 g of glucose per kg of body weight. If the weight is in pounds, divide by 2.2 to get kg. Do not provide more than 75 g dose regardless of body weight. |
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| Container type | Gray top, Gold top acceptable | ||||||
| Amount to Collect | 1 mL blood Click here for Microdetermination info | ||||||
| Sample type | Serum | ||||||
| Preferred volume | 0.5 mL serum | ||||||
| Min. Volume | 0.2 mL serum Click here for Microdetermination info | ||||||
| Units | mg/dL | ||||||
| Normal range |
* If confirmed on another day by repeat OGT, or a diagnostic elevation of the fasting or non-fasting glucose. |
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| Synonyms | Diabetes mellitus | ||||||
| Stability | Room temperature 8 hours, refrigerated 2 days | ||||||
| Additional information | Based on 75 g dose ingested over 5 minutes. THIS TEST IS NO LONGER RECOMMENDED FOR ROUTINE USE. When performed,it is abbreviated to a single 2 hour post-glucose specimen. All patients should be screened with a fasting glucose: Do not perform this test if the fasting glucose exceeds 125! 90% of patients whose 2 hour level is > 199 mg/dL have fasting hyperglycemia, obviating the need for tolerance testing. Glucose tolerance beverages are available in 100 g bottles (10 g/fl. oz. at 10 oz.) at ACC, and 100 g and 50 g bottles (10 g/fl. oz., 5 g/fl. oz.both 10 oz.) at Post St. Reference values from position statement of the American Diabetes Association on Diagnosis and Classification of Diabetes (Diabetes Care, Volume 34, Supplement 1, January 2011). |
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| Last Updated | 9/18/2012 2:34:26 PM | ||||||
| Entry Number | 1030 | ||||||
| Lab Procedure Link | Click here for Procedure |
If you have additional questions regarding this test, please call: 415-353-1667