Hb Ube-2 in a diabetic case with an abnormally low HbA1C value.

A 69-year-old male diabetic patient had an abnormally low HbA1C value of 2.8%, which was inconsistent with his elevated fasting plasma glucose of 8.2 mmol/l. Hb analysis disclosed that the abnormal Hb was Hb Ube-2 [alpha68 (E17) Asn --> Asp] and it accounted for 21.5% of the total Hb. Since the glycated abnormal Hb emerged at the same position as did HbF on high performance liquid chromatography, the HbA1C value was falsely low. The present case demonstrates that Hb Ube-2 is one of the abnormal Hbs in which caution should be exercised when monitoring diabetic control.