| Title | Hb I: A alpha-globin chain variant causing unexpected HbA(1c) results |
| Authors | Xu, Anping Sun, Jian Li, Jie Chen, Weidong Zheng, Ruoyang Han, Zhonghou Ji, Ling |
| Affiliation | Peking Univ, Shenzhen Hosp, Dept Clin Med Lab, Shenzhen, Peoples R China Qinhuangdao Maternal & Child Hlth Hosp, Dept Lab Med, Qinhuangdao, Peoples R China |
| Keywords | capillary electrophoresis Hb I HbA(1c) hemoglobin variants HPLC |
| Issue Date | 2019 |
| Publisher | JOURNAL OF CLINICAL LABORATORY ANALYSIS |
| Abstract | Background HbA(1c) is the standard bio-marker for glycemic control in patients with diabetes. Here, we report a alpha-globin chain variant and evaluate its effect on HbA(1c) measurements. Methods A 21-year-old female was suspected of harboring a hemoglobin variant following HbA(1c) measurement during a routine examination using Variant II Turbo 2.0 (Bio-Rad). An oral glucose tolerance test was performed using an AU5800 clinical chemistry system (Beckman Coulter). HbA(1c) was reanalyzed using D10 (Bio-Rad), Capillarys 2 Flex Piercing (Sebia), and Premier Hb9210 (Trinity Biotech). Hemoglobin analysis was performed using high-performance liquid chromatography (HPLC) on the Bio-Rad Variant II (beta-thalassemia short program) and capillary electrophoresis (CE, Capillarys 2 Flex Piercing, Hb program). Sanger sequencing of alpha and beta genes was also conducted. Results HbA(1c) was initially measured at 24.2% using Variant II Turbo 2.0. For the oral glucose tolerance test, fasting glucose, 1-hour, and 2-hour levels were recorded as 4.25, 7.89, and 5.34 mmol/L, respectively. Subsequently, HbA(1c) values determined by D10, Capillarys 2 Flex Piercing (HbA(1c) program), and Premier Hb9210 were 4.5% (26 mmol/mol), no HbA(1c) value, and 4.8 (29 mmol/mol), respectively. Hemoglobin analyzed using CE and HPLC revealed an abnormal hemoglobin. Sanger sequencing identified a transversion mutation of the alpha 2 gene [CD16(AAG>GAG), Lys>Glu, HBA2: c.49 A>G], corresponding to a Hb I variant. Conclusion An unusually high HbA(1c) or discordance between blood sugar and HbA(1c) values should alert about the possibilities of hemoglobin variants. |
| URI | http://hdl.handle.net/20.500.11897/551005 |
| ISSN | 0887-8013 |
| DOI | 10.1002/jcla.22671 |
| Indexed | SCI(E) |
| Appears in Collections: | 深圳医院 |
