Glucose

The Glucose test, also known as blood glucose or blood sugar, is used to establish and monitor the diagnosis of diabetes mellitus and other disturbances of carbohydrate metabolism. It supports assessment of hyperglycemia and hypoglycemia, and it assists in evaluating acidosis, ketoacidosis, dehydration, coma, and neuroglycopenic symptoms, including those resulting from insulinoma. For diagnosis, fasting plasma glucose (FPG) or an oral glucose tolerance test may be performed, with any abnormal value confirmed on a different day. Screening for gestational diabetes typically occurs at 24–28 weeks of pregnancy. Plasma glucose measurements are also used to track glycemic control in conjunction with other markers.

Glucose is a simple sugar that serves as the principal energy source for most tissues. Dietary carbohydrates are broken down into glucose and other monosaccharides, absorbed through the small intestine, and delivered to the circulation. Pancreatic insulin facilitates cellular uptake, promotes glycogen synthesis, and supports triglyceride storage, whereas glucagon drives hepatic glycogenolysis when plasma glucose declines with fasting or exertion. In an intact feedback loop, postprandial rises in blood glucose stimulate insulin release, maintaining a relatively narrow plasma glucose range. Disruption of this regulatory system produces hyperglycemia or hypoglycemia. Severe deviations may lead to organ dysfunction, neurologic injury, or coma. Sustained hyperglycemia is linked with microvascular and macrovascular complications that affect the kidneys, eyes, peripheral nerves, and cardiovascular system. Hyperglycemia arising during pregnancy (gestational diabetes) requires timely diagnosis and management to mitigate maternal and neonatal risks.