erythrocyte surface comprises a sufficient amount of antigens (proteins).They provide an opportunity to explore the genetic (inherited) characteristics of each person.A major manifestation of hereditary traits is blood.
Blood - it is a combination of certain protein molecules (or antigens) that every person is different and depends on the genetic information inherited from parents.
Modern medicine has identified two types of proteins - A antigen and B antigen.Their combination divides people into groups of blood.There are four main blood groups:
- first (0) - the presence of alpha and beta antibodies in the blood plasma;
- II (A) - In the presence of antigen on the surface of erythrocytes, and B antigen - in the blood plasma;
- third (B) - In the presence of antigen in the blood plasma of antigen and B - on the surface of erythrocytes;
- fourth (AB) - the presence of alpha and beta antibodies on the surface of red blood cells only.
name blood group is determined by means of the AB0 (a, b, and zero) sys
human blood groups can be found with a blood test in a normal clinic.Also, medical laboratory blood test on the Rh factor.
Blood test for Rh factor and group
analysis on blood group and Rh - a microscopic examination of the blood, which makes it possible to establish the blood group system AB0 and Rh affiliation to determine any person.
Rh factor (Rh-factor) - is also a protein (antigen), it does not depend on the presence of human blood groups and external factors.There are five basic antigens, but the most isolated immunogenic antigen D. It is this type of protein is the Rh factor.It is constant throughout life.Almost 85% of people of such a blood test gives a positive result.They are called Rh positive.All others (ie 15%) believe Rh-negative people.
analysis on blood group and Rh carried out prior to transfusion of blood and its components.Also, this kind of research - one of the first, which is used for observation during pregnancy.A blood test to establish the Rh factor helps doctors in the early stages to identify threats to the life of the expectant mother and the child.If a woman is Rh positive, there is no special hazards.But in case of a negative Rh factor incompatibility may arise for Rh blood group-antigen.Medical experts attribute this to the rhesus ongoing conflict.The fact that in the presence mum negative Rh-antigen positive and in the child, the protein from the blood toddler enters the body of a pregnant woman.At the same time the body perceives the mother the fetus as a foreign object and begins to produce protective antibodies to the baby.Penetrating through the placenta into its blood, red blood cells are destroyed by the unborn child, and emit large amounts of bilirubin.A baby may be anemia (hemolytic disease), which will lead to the pathologies of hearing and speech, as well as hemolytic jaundice at birth.In addition, when such combinations rhesus mother and child, there is a high probability of fetal loss.Therefore, during pregnancy the doctors attention is paid to the analysis of blood and Rh group.
great influence has the Rh factor in blood transfusions.A man who carried out the procedure, referred to as the recipient, and the person who give blood - donor.In the case of blood transfusion recipient with Rh-negative blood donations positive Rh factor, there is a development of destructive antibodies, as his body takes a blood as a foreign object.This process is called hemolysis.It can lead to undesirable consequences, not excluding even the death of the recipient.Therefore, in order to avoid blood transfusion is not compatible, the analysis of blood and Rh group.
As for the establishment of the Rh factor and blood group of the child, there may be noted an important feature.Determination of blood group and Rh factor is carried out on the washed red blood cells of the newborn.They are separated from whole blood and removal of plasma therefrom during centrifugation.After that, the red blood cells are washed with isotonic saline.Thus, a suspension of erythrocytes without the presence of plasma, platelets and leukocytes.
Another important feature of the analysis of blood and Rh group in the newborn is that the study itself is carried izogemaglyutiniruyuschey serum or monoclonal antibodies.Furthermore, when establishing Rhesus blood toddlers uses two series of reagents.They are called anti-D reagents.
also taken into account the fact that during childbirth could be conducted vnutripupovinnye blood transfusion with Rh-negative.This blood may contain up to 90% of the donor's red blood cells during analysis can result in incorrectly installed Rh factor of the child.That is Rh newborn may be as D-negative and weak positive.
When interpreting the results of the analysis on the blood group and Rh should remember that babies up to one year may lack antibodies A and B. This can affect the process of diagnosis of blood, as in wells with normal red blood cells will be no agglutination (adhesion of red blood cells).In this case, the decryption carried out studies to assess the process passes adhesion monoclonal antibodies.
How to take a blood test for the Rh factor?
blood test for the Rh factor as to hand over a complete blood count, experts recommend observing these rules:
- before taking a blood sample to avoid eating, drinking plain water;
- morning fasting blood surrenders (at least eight hours of hunger, but no more than fourteen), preferably with 8 and 11 am;
- be sure to consult the doctor before taking if the material were used for the study of drugs;
- eliminate emotional stress;
- smoke for an hour before the blood test for the Rh factor as to hand over the material to study the influence of alcohol is not recommended;
- avoid physical exhaustion;
- should rest 10-20 minutes after the arrival of the lab;
- physiotherapy before the blood test for the Rh factor as to hand over a blood sample after the Diagnostics, recommend that you wait for a few days;
- for the reliability of analyzes required to pass a secondary diagnosis, and in the same medical laboratories and under the same conditions.
basically a blood test for the Rh factor is used to determine the compatibility of transfusion (blood transfusion) and hemolytic disease of the newborn.And in preparation for operations of various types and during pregnancy (for the control of rhesus incompatibility between mother and baby).