Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Case Reports
. 2020 Mar 15;59(6):805-809.
doi: 10.2169/internalmedicine.3306-19. Epub 2019 Nov 29.

Hb Phnom Penh Showing Falsely High or Reasonable HbA1c Values Depending on the Type of High-performance Liquid Chromatography System

Kenji Hara  1 , Masafumi Koga  2 , Hiroyuki Shinozaki  1 , Mototaka Yamauchi  1 , Tatsuhiko Suzuki  1 , Rika Naruse  1 , Takafumi Tsuchiya  1 , Kohzo Takebayashi  1 , Toshihiko Inukai  1 , Koshi Hashimoto  1
Affiliations
Case Reports

Hb Phnom Penh Showing Falsely High or Reasonable HbA1c Values Depending on the Type of High-performance Liquid Chromatography System

Kenji Hara et al. Intern Med. .

Abstract

We herein report a 50-year-old Chinese woman with Hb Phnom Penh (α117Phe-Ile-α118Thr) showing high or reasonable HbA1c values depending on the type of high-performance liquid chromatography (HPLC) system. A high HbA1c value of 7.5% (HPLC assay: G9) and a reasonable HbA1c value of 5.2% (assay unknown) were observed. Therefore, the patient was refereed to our hospital; the oral glucose tolerance test showed normal glucose tolerance. The HbA1c values measured by an enzymatic assay, immunoassay, and affinity assay, as well as most HPLC assays were within the reference range, whereas those measured by the Tosoh HPLC systems were high.

Keywords: Hb Phnom Penh; HbA1c; high performance liquid chromatography; variant hemoglobin.

PubMed Disclaimer

Conflict of interest statement

The authors state that they have no Conflict of Interest (COI).

Figures

Figure 1.
Figure 1.
Results of the globin gene analysis. PCR amplification was performed with DNA extracted from white blood cells for the globin gene analysis with a direct sequencing assay. Nucleotide sequences at between positions 116 and 120 of the α1 chain in this case are shown. The insertion of three nucleotides of ATC (isoleucine) was identified between positions 117 and 118.
Figure 2.
Figure 2.
Chromatograms obtained using the standard mode of Tosoh HPLC systems. Chromatograms obtained using the standard mode of Tosoh HPLC systems G7 (A), G8 (B), and G9 (C) in the present case are shown. The black areas represent HbA1c. White arrows A and C indicate elevated baseline values of HbA1c and HbA0. Arrow B indicates an abnormal peak in which part of the area may have been associated with HbX0.
Figure 3.
Figure 3.
Chromatograms obtained using the variant mode of Tosoh HPLC system. Chromatograms obtained using the variant mode of Tosoh HPLC system (G8) in the present case are shown. A: control sample, and B: sample obtained from this case.
See this image and copyright information in PMC

References

    1. American Diabetes Association Standards of medical care in diabetes; Glycemic targets. Diabetes Care 40（Suppl 1）: S48-S56, 2017. - PubMed
    1. Koga M. Glycated albumin; clinical usefulness. Clin Chim Acta 433: 96-104, 2014. - PubMed
    1. Miyazaki A, Kohzuma T, Kasayama S, Koga M. Classification of variant forms of haemoglobin according to the ratio of glycated haemoglobin to glycated albumin. Ann Clin Biochem 49: 441-444, 2012. - PubMed
    1. Bry L, Chen PC, Sacks DB. Effects of hemoglobin variants and chemically modified derivatives on assays for glycohemoglobin. Clin Chem 47: 153-163, 2001. - PubMed
    1. Wajcman H, Préhu MO, Préhu C, Blouquit Y, Promé D, Galactéros F. Hemoglobin Phnom Penh [α117Phe(H1)-Ile-α118Thr(H2)]; evidence for a hotspot for insertion of residues in the third exon of the α1-globin gene. Hum Mutat (Suppl 1): S20-S22, 1998. - PubMed

Publication types