A 30-year-old woman with autoimmune haemolytic anaemia has a fasting plasma glucose of 108 mg/dL but an HbA1c of 5.1%. Her clinician suspects her glycaemic status over recent weeks is not reflected by this value. Which test best reflects her average glucose over the preceding 2 to 3 weeks?

• A Repeat HbA1c from a different laboratory
• B Urinary albumin-to-creatinine ratio
• C Random capillary glucose
• D Serum fructosamine ✓

Explanation

Fructosamine reflects non-enzymatic glycation of serum proteins, chiefly albumin, whose half-life is about 2 to 3 weeks, so it mirrors shorter-term glycaemia than HbA1c. Haemolysis shortens red cell survival and falsely lowers HbA1c, so repeating it is misleading. Fructosamine itself is affected by hypoalbuminaemia, not by haemolysis.

Reference: Harrison's Principles of Internal Medicine, 21st ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.