Hemoglobin A2 (HbA2) is a normal variant of hemoglobin A that consists of two alpha and two delta chains (α 2 δ 2) and is found at low levels in normal human blood. Hemoglobin A2 may be increased in beta thalassemia or in people who are heterozygous for the beta thalassemia gene.

Hemoglobin (Hb) A2' is a hematologically silent variant of HbA2 that is detected easily by high-performance liquid chromatography (HPLC), where it elutes in the S window. Our purposes were to define diagnostic criteria for the HbA2' trait using the Variant II …

The increase in hemoglobin A2 (HbA2) level is the most significant parameter in the identification of β-thalassemia carriers. HbA2, composing of two α chains and two δ chains, is a minor component of the hemoglobin present in normal adult red blood cells, accounting for about 2.5% of the total hemoglobin in healthy individuals.

2018年1月25日 · In particular, the percentage of hemoglobin (Hb) A 2 is elevated, while the red cell mean corpuscular volume (MCV) and/or mean corpuscular hemoglobin (MCH) are decreased. The red blood cell count is usually normal or increased, but may be decreased if the patient has other causes of anemia.

What does it mean if your Hemoglobin A2 (Quant) result is too high? Elevated levels of Hemoglobin A2 (HbA2) in a blood test can indicate certain health conditions, most notably beta thalassemia, a blood disorder. Hemoglobin is a protein in your red blood cells that carries oxygen throughout your body.

2023年5月1日 · A diagnosis of beta-thalassemia requires hemoglobin electrophoresis or high-performance liquid chromatography (HPLC) to demonstrate abnormal percentages of HbA, HbA2, and sometimes HbF. The general pattern of beta-thalassemia is a decreased HbA percentage and a mildly increased HbA2; less than 10% with variably increased HbF.

A: The normal Hb A2 level in an adult is less than 3.5% and it is elevated (>4%) in b-thalassaemia trait. Your Hb A2 value lies in the indeterminate range. Beta thalassaemia trait (or...

2024年7月23日 · In this study, among 213 children with β-thalassemia trait, those with iron deficiency were determined based on ferritin value (<15 ng/mL), and their HbA2 levels were examined. We compared HbA2 levels of iron-deficient and iron-sufficient carriers and examined the correlation between low HbA2 levels and ferritin level.

2018年11月29日 · High-Performance Liquid Chromatography (HPLC) overestimates HbA2 in patients with Sickle Cell Disease (SCD) due to the co-elution of HbS in HbA2 column. The optimal cut-off level of HbA2 to indicate the presence of beta thalassemia trait has not been well established in patients with SCD.

Hemoglobin A2 levels in normal adults are rarely greater than 3.5%. In patients heterozygous for beta-thalassemia, they average about 5% but do not usually exceed 7%. We studied a family in which four patients with heterozygous beta-thalassemia had HbA2 levels of 8.4% to 11.2%.