Comparison Study of The Results of Glycosylated Hemoglobin Assay by Two Methods of High-Performance Liquid Chromatography (HPLC) and Fluorescence Immunoassay (FIA)

Abstract

Background: HbA1c is the gold standard for controlling and monitoring blood glucose levels in diabetic patients, thus detecting disease processes early and preventing complications. Therefore, it was important to shed light on the most important methods used to calibrate HbA1c and choose those that are characterized by reliability, quality and good sensitivity, which ensures high quality laboratory results.

Objectives: Comparison of methods used to measure HbA1c and determine the optimal cut-off values ​​in healthy individuals and diabetic patients using two different methods: high-performance liquid chromatography (HPLC) with one of the immunoassay methods (FIA).

Materials and Method: The research sample included 72 patients with type 2 diabetes mellitus who visited the Endocrinology Clinic at Latakia University Hospital and 42 healthy controls. Their HbA1c and fasting blood sugar were measured using the devices available in the central laboratory at Latakia University Hospital during the period 2022-2023.

Results: The levels of HbA1c measured by HPLC were higher than those measured by FIA, and there was a good direct correlation between the values ​​of HbA1c measured by the two previous methods in the study group, which was statistically significant. The cut-off value was 6.5%, which combined the best sensitivity and specificity when applying HPLC. While the cut-off value was 6.3% when applying FIA for diagnosing diabetes. While the cut-off value was 5.5% when applying HPLC and 5.4% when applying FIA, which are the optimal values ​​for detecting pre-diabetes.

Conclusions: The FIA ​​method is good for measurement but not very accurate while the HPLC method provides more accurate and stable results.