A case of inappropriately high glycated hemoglobin.

Hemoglobin is a tetramer formed of two alpha and two beta globin chains. On exposure to high levels of blood glucose, hemoglobin gets non-enzymatically glycated at different sites in the molecule. HbA1c is formed when glucose gets added on to the N-terminal valine residue of the beta chain of hemoglobin. The development of chronic vascular complications of diabetes such as retinopathy, nephropathy and cardiovascular disease is intimately linked to the level of glycemic control attained by the individual with diabetes. We report a case of convulsions and monoplegia admitted to emergency department, showing unusually high glycated hemoglobin but plasma glucose not as high. The patient was not a known diabetic and we could not find any of the other documented conditions that are known to elevate glycated hemoglobin to such disproportionately high levels. Screening for abnormal hemoglobins was negative in the patient. Oral hypoglycemic drug treatment over 3 months and withdrawal of other medications only marginally lowered glycated hemoglobin.