Glucose in the blood, plasma, serum (blood sugar)

Indications for measuring glucose in a blood test are suspicions of hyper- or hypoglycemia, or for diagnostics and control of diabetes mellitus. The reference area is for a test taken in a fasting state (8 hours).

Glucose (plasma) fasting 4,2-6,3 mmol/L

Hyperglycemia is seen in absolute or relative insulin deficiency (respectively, type 1 and type 2 diabetes mellitus), or under an excess of hormones that mobilise glucose to the blood (glucagon, adrenaline, cortisol, growth hormone). Hyperglycemia can be transient in an acute situation such as a myocardial infarction, increased intracerebral pressure, acute pancreatitis, acute liver damage, hypoxia, and thiazide use.

Diagnostic criteria for diabetes mellitus

HbA1c ≥ 6,5 %; or
Fasting plasma/serum-glucose ≥ 7,0 mmol/L; or
Plasma/serum-glucose ≥ 11,1 mmol/L two hours after an oral glucose tolerance test (75 g); or
Random plasma/serum-glucose ≥ 11,1 mmol/L and symptoms of acute hyperglycemia or diabetic coma.

For the first three criteria, the results must be verified by repeating the test.

Hypoglycemia occurs after overdosing on drugs used in the treatment of diabetes (insulin, sulphonylurea), in insulin producing tumors, pituitary and adrenal gland failure, and nutrition deficiency.
Read more about glucose in The handbook on medical biochemistry: