[Hemoglobin A1C determination and hemoglobinopathies: problems and strategies]

Area of Science:

• Clinical Chemistry
• Hematology
• Diabetology

Background:

• Hemoglobin A1c (HbA1c) is a key marker for assessing long-term glycemic control in diabetes.
• Hemoglobinopathies, genetic disorders affecting hemoglobin structure or synthesis, can significantly interfere with HbA1c measurements.
• This interference compromises the diagnostic and monitoring accuracy of HbA1c in affected individuals.

Purpose of the Study:

• To review the methodological and semiological challenges posed by abnormal hemoglobin variants in HbA1c testing.
• To highlight the impact of hemoglobinopathies on the reliability of HbA1c as a marker of glycemic control.
• To propose a standardized strategy for managing HbA1c assessments in patients with hemoglobinopathies.

Main Methods:

• Literature review of studies investigating HbA1c assay interferences in the presence of hemoglobin variants.
• Analysis of the biochemical mechanisms by which abnormal hemoglobins affect HbA1c glycation and assay methodologies.
• Evaluation of existing guidelines and proposed solutions for accurate glycemic monitoring in patients with hemoglobinopathies.

Main Results:

• Abnormal hemoglobins create methodological interferences in most HbA1c assay methods.
• The glycation process of hemoglobin A to HbA1c is altered by abnormal hemoglobin species.
• Hemolysis, often induced by hemoglobinopathies, adds variable and unquantifiable interference, further weakening HbA1c's semiological value.

Conclusions:

• The diagnostic utility of HbA1c is significantly diminished in patients with hemoglobinopathies.
• Accurate glycemic assessment requires addressing the specific interferences caused by abnormal hemoglobins.
• A standardized approach is necessary to overcome these challenges and ensure reliable diabetes management in this population.