From the Guidelines
Elevated hemoglobin (Hb) electrophoresis results are primarily caused by hemoglobinopathies, which are genetic disorders affecting the structure or production of hemoglobin molecules. The most common causes include beta-thalassemia trait, which shows increased hemoglobin A2 (typically 3.5-8%) 1; hemoglobin S trait (sickle cell trait), with hemoglobin S levels of 35-45% 1; and hemoglobin C trait, showing hemoglobin C levels of 30-40%. Other causes include:
- Hemoglobin E trait
- Hereditary persistence of fetal hemoglobin (HPFH) with elevated hemoglobin F in adults
- Homozygous conditions like sickle cell disease (predominantly hemoglobin S) or hemoglobin C disease Certain acquired conditions can also affect results, such as recent blood transfusions which may show mixed hemoglobin patterns 1. Laboratory errors during sample collection, processing, or analysis can occasionally lead to falsely elevated results. Understanding these causes is important for proper diagnosis and management of hemoglobinopathies, as they have varying clinical implications ranging from asymptomatic carrier states to severe hematological disorders requiring specific treatments and genetic counseling 1.
It is essential to consider the clinical context and perform a thorough evaluation to determine the underlying cause of elevated Hb electrophoresis results, as some conditions may require specific treatments or genetic counseling 1. In some cases, additional testing such as iron studies or molecular analysis may be necessary to confirm the diagnosis 1. By prioritizing the diagnosis and management of hemoglobinopathies, healthcare providers can improve patient outcomes and reduce the risk of complications associated with these conditions.
From the Research
Causes of Elevated Hb Electrophoresis
Elevated Hb electrophoresis results can be caused by various factors, including:
- Hemoglobinopathies, such as sickle cell disease and beta-thalassemia 2, 3, 4, 5
- Abnormal hemoglobin variants, such as HbS and HbE 4, 5, 6
- Red blood cell transfusions, which can lead to delayed hemolytic transfusion reactions (DHTR) and hyperhemolysis syndrome (HHS) 2
- Inheritance of multiple alleles, such as HbS and beta-thalassemia, which can result in sickle cell syndrome 5
- Point mutations, such as the mutation responsible for HbS, and deletions or insertions, such as those found in beta-thalassemia 5
Hemoglobinopathies and Electrophoresis
Hemoglobin electrophoresis is a useful tool in diagnosing hemoglobinopathies, including:
- Sickle cell disease, which can be diagnosed by the presence of HbS 4
- Beta-thalassemia, which can be diagnosed by the presence of abnormal hemoglobin variants, such as HbA2 3, 5
- HbE syndromes, which can range from asymptomatic to severe and require distinction from other hemoglobinopathies 6
Clinical Implications
Accurate diagnosis of the cause of elevated Hb electrophoresis results is crucial for: