Diabetes Defined by Elevated Blood Glucose

Steps:

• Recall diabetes mellitus as a condition where the body cannot regulate blood sugar properly due to insulin issues.
• Identify key diagnostic signs: hyperglycemia (high blood glucose) is the hallmark.
• Evaluate choices: focus on direct indicators of impaired glucose metabolism.
• Select the option matching the primary biochemical sign.

Why B is correct:

• Diabetes mellitus is defined by chronic hyperglycemia, where blood glucose exceeds 126 mg/dL fasting, per WHO criteria, due to insufficient insulin action.

Why the others are wrong:

• A: Glucose in urine (glycosuria) occurs secondary to high blood glucose overwhelming kidney reabsorption, not the primary sign.
• C: Insulin in blood varies; type 1 diabetes shows low levels, but presence alone isn't diagnostic.
• D: Insulin is not typically found in urine, as it's a peptide hormone degraded in the body.

Final answer: B