Essay about The Oral Glucose Tolerance Test
Glucose is one of the few chemical constituents of the blood that can change noticeably in its concentration. Many diseases cause a change in glucose metabolism but the most frequent cause of an increase in blood glucose is diabetes mellitus. The early detection of diabetes is important to avoid the many complications of the disease. The glucose tolerance test commonly done by recommended level for adults of a 75 g glucose drink to be consumed within a 5 min time period. The timing begins when the drink has been consumed. This test is known as the oral glucose tolerance test (OGTT). For these reasons, the physician may request an OGTT. Normally when the body receives such a dose, the pancreas responds by excreting insulin …show more content…
Samples | Glucose conc. (mg/dL) | Glucose conc. (mmol/l) | Results | A0a & A0b | | | | A2a & A2b | | | | B0a & B0b | | | | B2a & B2b | | | | C0a & C0b | | | | C2a & C2b | | | | Da & Db | | | |
In diabetics, especially following ingestion of large amount of glucose administered by the OGTT, plasma glucose levels are expected to be very high often exceeding the glucose assay. So we dilute the samples to reduce the amount of glucose in the assay to get better accuracy. Say, sample A2 only needed to dilute 1 + 2 before use with distilled water (1 part of plasma and 2 mL of water). Non-diabetics don’t have such high levels of plasma glucose, so their samples don’t need to be diluted in order to be measured accurately.
Briefly describe one other enzymic method for glucose determination that is used in clinical laboratories:
Another enzyme used in glucose tests is hexokinase. The determination of glucose concentration is