A Rare Case of Variant Hemoglobin (Hb Yahata) Suspected Based on Inconsistent Plasma Glucose and HbA1c Levels

Intern Med. 2015;54(14):1771-5. doi: 10.2169/internalmedicine.54.4017. Epub 2015 Jul 15.

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.

Publication types

  • Case Reports
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Blood Glucose / genetics
  • Blood Glucose / metabolism*
  • Chromatography, High Pressure Liquid*
  • Glucocorticoids / administration & dosage*
  • Glucocorticoids / adverse effects
  • Glucose Tolerance Test
  • Glycated Hemoglobin / genetics
  • Glycated Hemoglobin / metabolism*
  • Glycated Serum Albumin
  • Glycation End Products, Advanced
  • Hemoglobins, Abnormal / genetics
  • Hemoglobins, Abnormal / isolation & purification*
  • Humans
  • Male
  • Middle Aged
  • Neuromyelitis Optica / blood
  • Neuromyelitis Optica / drug therapy*
  • Sequence Analysis, DNA
  • Serum Albumin

Substances

  • Blood Glucose
  • Glucocorticoids
  • Glycated Hemoglobin A
  • Glycation End Products, Advanced
  • Hemoglobins, Abnormal
  • Serum Albumin
  • hemoglobin A1c protein, human
  • hemoglobin Yahata
  • Glycated Serum Albumin