A Methods Comparison Study of glycosylated haemoglobin.

Devina Govender, Professor A Motala


The American Diabetes Association (ADA) has recently recommended the use of glycosylated haemoglobin, HbA1c (A1c/GHb) for the diagnosis of diabetes mellitus.


HbA1c values may be affected by other conditions (eg. haemoglobinopathy, pregnancy, uraemia, blood transfusion and haemolytic anaemia) and depending on the laboratory method used, may confound the diagnosis of diabetes. Most methods used are subject to interference; mass spectrometry is the only method free from interferences but is limited to research settings.


Iron deficiency and sickle cell anaemia affect HbA1c values irrespective of the methodology employed. Immunoassays and boronate affinity chromatography can produce spurious results in the presence of high foetal haemoglobin as in the case of thalassaemia.


The proposed study is to be undertaken to evaluate the 3 commonly used methodologies for HbA1c and it is hoped that the results of the study will aid in determining which method is best for patients in Kwa Zulu Natal.