title: A Rare Case of Variant Hemoglobin (Hb Yahata) Suspected Based on Inconsistent Plasma Glucose and HbA1c Levels.
abstract: A 52-year-old man presented for an evaluation of worsening glycemic control secondary to glucocorticoid administration. The glycated hemoglobin (HbA1c) level was 8%, and oral glucose tolerance testing revealed impaired tolerance, whereas the plasma glucose and glycoalbumin levels were normal. The results of high-performance liquid chromatography (HPLC) for HbA1c, isoelectrofocusing of the hemolysate and precise HPLC measurements of the HbA1c level supported the presence of an Hb variant, and DNA sequencing of the β-globin gene revealed Hb Yahata [β112 TGT (Cys)→TAT (Tyr)] (heterozygote). In this case, the discrepancy between the plasma glucose and HbA1c levels raised suspicion of this rare Hb variant.
authors.affiliation: Department of Diabetes and Endocrinology, Graduate School of Medicine, Gifu University, Japan.
authors.forename: Katsumi
authors.initials: K
authors.lastname: Iizuka
authors.forename: Masami
authors.initials: M
authors.lastname: Mizuno
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Niwa
authors.forename: Jun
authors.initials: J
authors.lastname: Takeda
mesh_terms: D001786:Blood Glucose / Q000235:genetics / Q000378:metabolism*; D002851:Chromatography, High Pressure Liquid; D005938:Glucocorticoids / Q000008:administration & dosage* / Q000009:adverse effects; D005951:Glucose Tolerance Test; D006442:Glycated Hemoglobin / Q000235:genetics / Q000378:metabolism*; D017127:Glycation End Products, Advanced; D006455:Hemoglobins, Abnormal / Q000235:genetics / Q000302:isolation & purification*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009471:Neuromyelitis Optica / Q000097:blood / Q000188:drug therapy*; D017422:Sequence Analysis, DNA; D012709:Serum Albumin; D000093423:Glycated Serum Albumin
chemical_list: D001786:Blood Glucose; D005938:Glucocorticoids; D006442:Glycated Hemoglobin; D017127:Glycation End Products, Advanced; D006455:Hemoglobins, Abnormal; D012709:Serum Albumin; D000093423:Glycated Serum Albumin; C517652:hemoglobin A1c protein, human; C071131:hemoglobin Yahata