Inaccurate hemoglobin A(1C) levels in patients with type 1 diabetes and hereditary persistence of hemoglobin F.

We report 2 African-American boys with type 1 diabetes and hereditary persistence of hemoglobin F. The diagnosis came to light after both patients exhibited inconsistent hemoglobin A(1C) (HbA(1C)) levels with respect to serum glucose measurements. This demonstrates the importance of frequent glucose monitoring and interpreting the HbA(1C) level in light of serum glucose measurements.