A diabetic case of Hb Riyadh with a low HbA1c value.
A 74-year-old male patient with diabetes mellitus and hypertension who had been treated for a long period was admitted to our hospital. Laboratory data on admission revealed high values for fasting blood sugar and fructosamine, 219 mg/dl and 389 mumol/l respectively, while the concentration of glycated hemoglobin (HbA1c) was low (3.0%). High performance liquid chromatography and isoelectric focusing analysis of the patient's Hb disclosed abnormal Hb with the content being 41.3%. The structural analysis indicated that this abnormal Hb was Hb Riyadh [beta 120 (GH3) Lys-->Asn]. The low value of HbA1c despite the high blood glucose level may be attributed to this abnormal hemoglobin.
First Department of Internal Medicine, Jikei University School of Medicine, Tokyo, Japan.
Y
Y
Maezawa
M
M
Yamauchi
T
T
Nakabayashi
K
K
Toshima
K
K
Ikeda
G
G
Toda
D000368:Aged; D015415:Biomarkers; D001786:Blood Glucose / Q000032:analysis; D002851:Chromatography, High Pressure Liquid; D003924:Diabetes Mellitus, Type 2 / Q000097:blood*; D019270:Fructosamine; D006442:Glycated Hemoglobin / Q000032:analysis*; D006455:Hemoglobins, Abnormal / Q000032:analysis*; D006595:Hexosamines / Q000032:analysis; D006801:Humans; D007525:Isoelectric Focusing; D008297:Male
D015415:Biomarkers; D001786:Blood Glucose; D019270:Fructosamine; D006442:Glycated Hemoglobin; D006455:Hemoglobins, Abnormal; D006595:Hexosamines; C081658:hemoglobin Riyadh