Clinical utility of nonenzymatically glycosylated blood proteins as an index of glucose control.
This study compares the utility of nonenzymatically glycosylated serum proteins (lys-GSP) to glycosylated hemoglobins (HbA1a-c) as control indices of glucose homeostasis in patients with IDDM. The diagnostic value of lys-GSP was also examined in patients with non-insulin-dependent diabetes mellitus, in subjects with impaired glucose tolerance, and in two patients with insulinoma. The intraindividual fluctuation of lys-GSP in normoglycemic subjects is very small, resulting in an interindividual range of 3.0 +/- 0.3 lysine-bound glucose/mg protein (means +/- SD, N = 52). HbA1a-c with a normal range of 6.4 +/- 0.9% (N = 52) shows greater variability. In IDDM there is no overlap of lys-GSP levels between the normal and the diabetic range at the 95% confidence level. In patients treated with an open-loop insulin delivery system failure of normalization of the glucose balance was clearly discernible by an elevation of GSP. In contrast, in about 40% of the patients with incomplete glycemic control the HbA1a-c levels fell within the normal range. The utility of lys-GSP for diagnosis of diabetes is compared with the results of 60 oral glucose tolerance tests. Two patients suffering from insulinoma displayed decreased lys-GSP values. From these results it appears that determination of lys-GSP represents a more sensitive parameter for long-term control than HbA1a-c and is suitable for monitoring even small fluctuations of blood glucose.
D000293:Adolescent; D000328:Adult; D000368:Aged; D001786:Blood Glucose / Q000378:metabolism*; D001798:Blood Proteins / Q000378:metabolism*; D002648:Child; D002851:Chromatography, High Pressure Liquid; D003922:Diabetes Mellitus, Type 1 / Q000097:blood*; D003924:Diabetes Mellitus, Type 2 / Q000097:blood*; D005260:Female; D005951:Glucose Tolerance Test; D006442:Glycated Hemoglobin / Q000378:metabolism*; D017127:Glycation End Products, Advanced; D006023:Glycoproteins; D006801:Humans; D007340:Insulinoma / Q000097:blood; D008297:Male; D008875:Middle Aged; D010190:Pancreatic Neoplasms / Q000097:blood; D012709:Serum Albumin / Q000378:metabolism; D000093422:Glycated Serum Proteins; D000093423:Glycated Serum Albumin
D001786:Blood Glucose; D001798:Blood Proteins; D006442:Glycated Hemoglobin; D017127:Glycation End Products, Advanced; D006023:Glycoproteins; D012709:Serum Albumin; D000093422:Glycated Serum Proteins; D000093423:Glycated Serum Albumin