Recent blood transfusion can cause an artificially low hemoglobin A1c (HbA1c). Options for follow-up include monitoring home blood sugar readings; checking a fructosamine (glycosylated albumin) level, which reflects blood sugar control over the previous couple of weeks and is unaffected by transfusion; or waiting to recheck HbA1c after three months.
—Jennifer E. Frank, MD, Appleton, Wis. (112-25)