Hemoglobin electrophoresis is a diagnostic technique that aims to identify the different types of hemoglobin circulating in the blood. Hemoglobin or Hb is a protein found in red blood cells responsible for oxygen binding, allowing transport to tissues.Learn more about hemoglobin.
From the identification of the type of hemoglobin, it is possible to check whether the person has a disease related to the synthesis of hemoglobin, such as thalassemia or sickle cell disease, for example.testing is required.
- Hemoglobin electrophoresis is necessary to identify structural and functional changes associated with hemoglobin synthesis.
- So your doctor may recommend it to diagnose sickle cell disease.
- Hemoglobin C and differentiate thalassemia.
- For example.
In addition, it may be requested for the purpose of genetically advising couples who would like to have children, for example, to be informed if there is a risk that the child has any type of blood disorder related to hemoglobin synthesis.Hemoglobin electrophoresis may also be prescribed as a routine examination for the follow-up of patients already diagnosed with different types of hemoglobin.
In newborns, the type of hemoglobin is identified through the heel puncture test, which is important for the diagnosis of sickle cell disease, for example.See what diseases are detected by testing the heel bite.
Hemoglobin electrophoresis is performed by taking a blood sample from a professional trained in a specialized laboratory, as incorrect sampling can cause hemolysis, i.e. red blood cell destruction, which can interfere with the result.Understand how blood is collected.
The sample should be taken with the fasting patient for at least 4 hours and the sample should be sent for laboratory analysis, in which the types of hemoglobin present in the patient are identified, in some laboratories it is not necessary to fast for collection, therefore it is important to consult the laboratory and the doctor about fasting for the examination.
The type of hemoglobin is identified by alkaline pH electrophoresis (about 8.0 – 9.0), which is a technique based on the rate of migration of the molecule subjected to an electric current, with band visualization depending on the size and weight of the molecule.Depending on the band model obtained, a comparison is made with the normal model and thus the identification of abnormal hemoglobins is performed.
Depending on the tape model presented, it is possible to identify the type of hemoglobin of the patient, hemoglobin A1 (HbA1) has a higher molecular weight, so no significant migration is noticed, while HbA2 is lighter, penetrating deeper into the gel.This tape model is interpreted in the laboratory and published as a report to the doctor and the patient, reporting the type of hemoglobin found.
Fetal hemoglobin (HbF) is present at higher concentrations in infants, however, as development progresses, HbF concentrations decrease while HbA1 increases, so the concentrations of each type of hemoglobin vary by age and are generally:
1 to 7 days of age: up to 84%;
8 to 60 days: up to 77%;
2 to 4 months: up to 40%;
4 to 6 months: up to 7.0%
7 to 12 months: up to 3.5%;
12 to 18 months: up to 2.8%;
Adult: 0.0 to 2.0%
However, some people have structural or functional changes related to hemoglobin synthesis, resulting in abnormal hemoglobins or variants, such as HbS, HbC, HbH and Barts Hb.
Thus, from hemoglobin electrophoresis, it is possible to identify the presence of abnormal hemoglobins and, using another diagnostic technique called HPLC, it is possible to check the concentration of normal and abnormal hemoglobins, which may be indicative of:
The presence of this type of hemoglobin indicates a serious disease known as fetal hydropesia, which can lead to stillbirth and therefore a miscarriage.Learn more about fetal hydropsy.
In the case of diagnosis of sickle cell anemia using the heel bite test, the normal result is HbFA (i.e., the baby has both HbA and HbF, which is normal), while the results of HbFAS and HbFS indicate a sickle cell trait and sickle cell anemia respectively.
Differential diagnosis of thalassemia can also be performed using HPLC-associated hemoglobin electrophoresis, in which alpha, beta, delta and gamma chain concentrations are verified, verifying the absence or partial presence of these globin chains and, depending on the result, determining the type of thalassemia Learn how to identify thalassemia.
To confirm the diagnosis of any hemoglobin-related disease, other tests, such as iron, ferritin, transferrin, measures, as well as a complete blood formula should be monitored.See how to interpret the blood formula.