Please note the following correction/clarifcation of a passage in the June 2015 Continuing Education article entitled, “HPLC: its continuing role in diabetes monitoring.” The relevant passage is on page 10 of the print edition.
Statement currently in article: According to NGSP, “Only HPLC utilizing ion-exchange chromatography measures HbA1c. Affinity columns measure any hemoglobin that has glucose attached regardless of its attachment point or its structure because the column binds the glucose portion of the molecule. Any variant hemoglobin that is present will be detected as glycated products.”16
Reference: 16. NGSP, HbA1c assay interferences. http://www.ngsp.org/interf.asp. Updated Sept. 2014.
Replacement statement: According to NGSP, “Laboratories use many different methods for measuring A1C, but some of these methods can give inaccurate results when the patient has a hemoglobin variant such as sickle cell trait or if there is an elevated level of fetal hemoglobin (HbF). Doctors or patients interested in getting information about the accuracy of a particular A1C method for patients with hemoglobin variants should first find out which method your laboratory is using.” 16
Reference: 16. NGSP, HbA1c assay interferences. http://www.ngsp.org/interf.asp.