Glucose

Function

Glucose is the primary source of energy for the body's cells and the only energy source for the brain and nervous system. The body maintains blood glucose levels within a narrow range through a complex interplay of hormones, primarily insulin (which lowers blood sugar) and glucagon (which raises it).

Why it is Ordered

Glucose testing is fundamental for screening, diagnosing, and monitoring metabolic health. It is routinely ordered as part of a Basic Metabolic Panel (BMP) or Comprehensive Metabolic Panel (CMP). It is used to:

• Screen for and diagnose Diabetes Mellitus and Prediabetes.
• Monitor patients with known hyperglycemia or hypoglycemia.
• Investigate symptoms such as excessive thirst (polydipsia), frequent urination (polyuria), and unexplained fatigue.

Associated Conditions

• Diabetes Mellitus (Type 1 and 2): Characterized by chronic hyperglycemia.
• Insulinoma: A rare tumor that produces excess insulin, leading to severe hypoglycemia.
• Cushing Syndrome: Excess cortisol can lead to elevated glucose levels.
• Pancreatitis: Inflammation of the pancreas can impair insulin production.

Clinical Implications

Chronic high glucose (hyperglycemia) leads to long-term damage to the kidneys, eyes, nerves, and cardiovascular system. Conversely, acute low glucose (hypoglycemia) can be life-threatening, causing confusion, seizures, or loss of consciousness.