Why is Blood Type Important?

Rh blood group system, meaning the Rhesus Macacus blood group system, is a blood group system of human beings, which can be divided into negative and positive. When a blood group D substance (antigen) is present on a person's red blood cells, it is called Rh-positive, which is represented by Rh (+); when D antigen is lacking, it is Rh-negative, which is represented by Rh (-). Most people are positive. The Rh system is probably the most complex system in the red blood cell group, and its importance is second only to the ABO system.
Rh Synonym Rh blood group (medicine) generally refers to Rh blood group system

Chinese name: Rh blood group system
Foreign name: Rhesus Macacus Blood Type

means: Rhesus blood group system
Classification: There are negative and positive

Rh blood group system blood group classification

Rh Yin-Yang Difference

According to the presence or absence of the Rh factor, Rh negative and Rh positive blood types can be distinguished. This blood type system becomes the Rh blood type system. Rh is the first two letters of the foreign name of the Rhesus Macacus. When Randsteiner and other scientists performed animal experiments in 1940, they found that Rh blood group antigens were present on red blood cells in rhesus monkeys and most humans, so they were named. Those with Rh agglutination on human red blood cells are Rh positive. Otherwise it is negative. In this way, the four main blood types of red blood cells A, B, O, and AB have been found, and they are divided into Rh positive and negative. With the continuous research on Rh blood group, it is believed that Rh blood system is probably the most complicated blood group in red blood cell blood group. The discovery of the Rh blood group has a very important role in guiding the transfusion work more scientifically and further improving the experimental diagnosis of neonatal hemolytic disease and maintaining the health of mothers and infants. According to the introduction of relevant data, Rh-positive blood types account for about 99.7% of the Han and most ethnic groups in China, and about 90% for individual ethnic minorities. In some ethnic groups abroad, the Rh-positive blood group is about 85%, of which the Rh-negative blood group is about 15% in European and American Caucasians.

RH-negative people cannot receive RH-positive blood because antigens in RH-positive blood will stimulate RH-negative people to produce RH antibodies. Re-infusion of RH-positive blood can lead to a hemolytic transfusion reaction. However, RH-positive people can receive blood from RH-negative people.

Note: RH and ABO blood types must be tested during blood transfusion

Rh positive blood

Rh-positive blood types are about 85%, and most people are Rh-positive, which is common. It can accept yin and yang blood of this blood type without symptoms.

Rh negative blood

Rh-negative blood is called "Panda blood". According to cultural archaeology, physiological evolution, ethnic distribution, and molecular clock theory, it may be the blood type of the "Western Continent" people in ancient times. Similarly, the Neanderthals, who entered directly from North Africa into Western Europe, quickly conquered Great Western Continent and established the first prehistoric civilization by leaps and bounds, perhaps due to a flood at the end of the Ice Age more than 10,000 years ago, Destroyed their civilization completely, some Westerners fled to Western Europe. Later, when Cromnon entered Europe, they merged with the Westerners, and Rh-negative blood gradually dispersed.

4.Rh-blood type

The Rh (-) gene is a recessive gene. When a parent of Rh (+) carries the Rh (-) gene and inherits Rh (-) to the offspring at the same time, the child behaves as Rh (-); when one of the parents is Rh (-), The chances that their children will be Rh (-) are increased, otherwise the chances are decreased.

The distribution of Rh (-) varies greatly by race, with a higher proportion among whites, about 15%, among the Chinese population; the distribution of Rh (-) in Xinjiang Uygur and other ethnic minorities is percent 5. Mongolians are close to one percent; Han people account for a very small proportion, only three-thousandths, and they are a rare blood type. If ABO and Rh blood type systems are considered at the same time, look for AB-type Rh (-) Opportunities for similar people are less than three ten thousandths, which is very rare.

Rh blood group system abnormality value

When the mother has developed antibodies, the child's father should also be tested. If the father is Rh-negative, then their child will also be Rh-negative (the fetus is not at risk for Rh hemolytic disease), and pregnant women do not need to be tested further. If the child's father is Rh-positive (or the Rh-type is unknown), the doctor will perform an amniotic fluid puncture on the sensitized pregnant woman-a puncture needle is inserted into the pregnant woman's abdomen to remove the amniotic fluid to detect the fetal Rh blood type. There is currently an experimental maternal blood test showing the prospect of determining the Rh blood group of the fetus in order to reduce the need for amniocentesis, because it still has a lower risk of miscarriage. If the fetus is Rh-positive (or the doctor has not performed amniocentesis and does not know the Rh blood type of the fetus), then the maternal and child health staff will test the level of Rh antibodies in pregnant women during different pregnancy periods. If the antibody level is high, the doctor will suggest special tests to determine whether the child has Rh hemolytic disease.

These tests include amniocentesis, fetal umbilical vein puncture, etc. Under the leadership of the B-ultrasound, doctors puncture a thin needle into the abdomen of a pregnant woman and enter the microvessels of the umbilical cord to obtain fetal blood samples. These tests assist in determining whether the fetus is anaemic and the severity of the anemia. These two tests usually need to be repeated every 2 to 4 weeks, so there is less risk of miscarriage. A recent study showed that an ultrasonography measuring the rapidity of fetal head arterial blood flow can more accurately determine whether the fetus is moderate to severe anemia (requires prenatal treatment) or mild anemia (usually does not require treatment). If this ultrasound-free fetus proves to be correct, it will ultimately reduce the need for amniocentesis and umbilical vein puncture to monitor the fetus' risk of Rh disease.

The Rh (-) gene is a recessive gene. When a parent of Rh (+) carries the Rh (-) gene and is passed on to the offspring at the same time, the child is expressed as Rh (-), and if the single parent is Rh (-), the child is Rh (-) Opportunities increase and vice versa.

ABO Rh blood group system ABO blood group

First: Rh-negative human serum does not contain anti-Rh lectin. After receiving Rh-positive blood for the first time, the imported red blood cells will not undergo agglutination, but after entering into the blood of the blood, the red blood cells containing Rh agglutinogen can cause the blood to produce anti-Rh lectin. In the future, when the recipient receives the blood of the Rh-positive person again, the transfused red blood cells may undergo an antigen-antibody reaction, which may cause agglutination. Therefore, clinically, when repeated blood transfusions are given to patients, even if the blood of the same donor is input, an interspersed blood matching test should be performed.

Second: Rh-negative women marry Rh-positive men. The woman may conceive an Rh-positive fetus. After the fetal red blood cells enter the mother for some reason, the mother produces anti-Rh agglutinin. If a woman becomes pregnant with a Rh-positive fetus again, the mother's anti-Rh lectin may enter the fetal blood through the placenta, causing the newborn to develop hemolytic anemia and die. If Rh-negative women had received Rh-positive blood at that time, the first pregnancy of Rh-positive fetuses would also cause hemolysis.

Another major feature in the blood is the Ganges factor. The Rhus factor is also read as Rh antigen and Rh factor, because it is named after the antigen on the rhesus red blood cells, and was first discovered in 1940. Each group of red blood cells may or may not have Rh factor, which is usually combined with ABO and placed behind the ABO blood group at the time of writing. Among them, O + type is the most common.

In the ABO blood group, the Rh type is very important. Mismatch (Rh + blood donated to Rh- people) will cause hemolysis. However, people with Rh + blood types can receive Rh- blood without problems. Unlike the antibodies of the ABO blood group system, the antibodies of the Rh blood group system are relatively small and can penetrate the placental barrier. A Rh- mother with a Rh + baby and a second Rh + baby may present with Rh (hemolytic disease). The mother developed antibodies against Rh + red blood cells during her first pregnancy. During the second pregnancy, the antibody lyses the blood of the second baby through the placenta. Individually, it is called neonatal hemolysis. This reflects that it is not necessary to produce, but if the baby has A or B antibodies, the mother is more likely. In conclusion, the mismatch of Rh factors may cause a small birth or the death of a mother. In the past, most babies were rescued with blood transfusions. At first, it was usually treated with anti-Rh (+) drugs. Rhogam or Anti-D were most commonly used. The blood type of each Rh- pregnant mother's baby should be found. If it is Rh +, the mother will fight Anti-D.

Rh blood group is the same as natural antibodies, so the first blood transfusion will not invent Rh blood group differences. However, after Rh-negative blood is delivered to Rh-negative blood recipients, immune anti-Rh antibodies can be produced. If Rh-positive blood is transfused again, hemolytic transfusion reactions can occur.

Rh-negative mothers conceive the fetus as Rh-positive, and the fetal red blood cells enter the mother through the placenta to stimulate the mother to produce anti-Rh antibodies, and then enter the fetus through the placenta. Because the anti-Rh antibodies produced by the first child are few, neonatal hemolytic disease occurs very often, and the anti-Rh antibodies produced by Rh-positive fetuses in the second pregnancy increase, which can cause neonatal hemolytic disease. If a Rh-negative pregnant woman has had a history of Rh-positive blood, or a miscarriage due to Rh blood group mismatch in the first child, fetal hemolysis may also occur in the first child.

Rh +, called "Rh positive" and "Rh dominant", shows that the human red blood cells have "Rh factor";

Rh-, called "Rh negative", "Rh recessive", means that human red blood cells have no "Rh factor"

Rh blood group system blood group inheritance

How is Rh hemolytic disease treated before the fetus is born?

Based on the results of the above or other reviews, doctors recommend early delivery to prevent pregnant women's Rh antibodies from damaging more fetal blood cells. After childbirth, if the child develops jaundice, he can be treated under special blue light (photochemical education). If photochemotherapy is not effective for jaundice, or if your child has poor blood, then blood transfusions may be needed. There are also some patients with Rh hemolytic disease that are so mild that they do not require treatment.

According to the data, people have greatly improved their prescriptions for treating severe Rh hemolytic disease. Retrogressive umbilical vein puncture in the 1980s became an important result of the treatment of Rh hemolytic disease. Severely sick fetuses at high risk of death can be treated with umbilical vein puncture as early as 18 weeks of pregnancy. More than 90% of children with severe Rh hemolytic disease survive after treatment. Rh immunoglobulins include antibodies against Rh substances. These antibodies can be bluntly adhered in the mother's blood and help to destroy Rh-positive fetal cells. In this way, the mother does not produce antibodies against Rh-positive fetal red blood cells, because the mother has eliminated Rh-positive fetal red blood cells before the body is sensitized or rejection occurs.

Rh The meaning of Rh blood group system Rh

If both parents are Rh negative, then their child will also be Rh negative. In this case, the child is not at risk of Rh disease, and the mother does not need to be injected with Rh immunoglobulin for treatment after childbirth. Even if the father is Rh-positive, he may carry the Rh-negative blood group gene, so the child has a 50% chance of inheriting the Rh-negative blood group. Because there is no complete insurance method to detect the fetal Rh blood group, even if the child is found to be Rh negative blood group after birth, pregnant women with Rh negative blood group should be injected with Rh immunoglobulin at 28 weeks. Of course, if the child is found to be Rh positive blood type, pregnant women should also be injected with Rh immunoglobulin after delivery!

1) The Rh-negative rate of Chinese Han people is 0.34%, and most people are Rh-positive. Therefore, the transfusion reaction caused by Rh type incompatibility is definitely less than that of ABO type.

2) A woman with Rh-negative blood group can be free of any disease symptoms and stay healthy all the time, but she can continuously produce Rh antibodies as part of her blood. If she is pregnant with a child with a Rh-positive blood group, the child may develop Rh hemolytic disease.

Anyone with Rh agglutinogen on human blood red blood cells is Rh positive, otherwise it is negative. In this way, the four main blood types of red blood cells A, B, O, and AB have been found, and they are divided into two types, Rh positive and negative. With the continuous research on Rh blood group, it is thought that Rh blood system is probably the most complicated blood group in red blood cell blood group. The discovery of the Rh blood group has an extremely important role in leading superstitions of blood transfusion and further improving the test diagnosis of neonatal hemolytic disease and protecting the health of mothers and infants. Roots account for the introduction of relevant materials. Rh-positive blood types account for about 99.7% of Chinese Han and most ethnic groups, and some ethnic minorities are about 90%. In China, RH-negative blood types account for only three to four thousandths. The ratio of RH negative A, B, O, and AB is 3: 3: 3: 1.

The distribution of Rh (feminine-) varies greatly by race, with a high proportion among red people, about 15%, among the Zhongbang population; the distribution of Rh (feminine) in most official ethnic groups such as Xinjiang Uygur is 5%; Mongolians are on the verge of 1%; the proportion of Han people is very small, accounting for only three-thousandths. It is a thick blood type. If you consider the ABO and Rh blood type systems at the same time, look for AB in the Han population. Type Rh (feminine) homosexuals have less than three-tenths of a chance and are extremely rare. RH-negative blood is also called panda blood. It refers to RH negative blood, which is an extremely rare blood type. Because it is extremely uncommon, it is called "panda blood".

Problems with Rh blood group system

Rh-negative people can be transfused into Rh-positive blood under urgent circumstances, but about 3 months after receiving Rh-positive blood for the first time, the blood will produce anti-Rh agglutinin. At this time, the blood can only be infused by the same type, that is, type A Rh (-) patients can only be transfused with Rh (-) blood type A, and Rh (-) type B blood can only be transfused. If you are sick or need blood transfusion for surgery, you must be Rh (-) blood type. Tell the doctor about the situation so that the doctor can contact the city blood station early to contact the Rh (-) blood source you need. If you are a married woman, please give birth less frequently to avoid spontaneous abortion. If you do not have a history of abortion or blood transfusion, you must go to the blood station blood type room during pregnancy to make a guess test for neonatal hemolytic disease to avoid future neonatal hemolytic disease.

RH-positive people can receive blood from RH-negative people, but RH-negative people cannot receive blood from RH-positive people, because the antigen in RH-positive blood will stimulate RH-negative people to produce RH antibodies. Re-infusion of RH-positive blood can lead to a hemolytic transfusion reaction.

According to statistics, the number of people with RH negative blood in China is about 3.9 million. Due to insufficient publicity on RH, many people do not understand this rare blood type, and even many RH negative blood people do not know their blood type when they encounter an accident and urgently need blood transfusion, which leads to the difficulty of timely treatment for all patients, thus There are some unwanted effects.

Another cause of poor results stems from hemolysis in the newborn. Because there is still a gap between China's medical level and the developed countries in the world, many hospitals are at a loss as to the hemolytic response of patients due to backward technology. They can only persuade pregnant women to go to the front-line hospital for treatment. Or in the stillbirth.

Rh Rh blood group system Rh hemolytic disease

Newborn Rh hemolytic disease is a hemolytic disease caused by the incompatibility of mother and fetal blood types, which can cause the destruction of fetal red blood cells. Without treatment, most severely ill fetuses will die. Rh hemolytic disease can also cause neonatal jaundice (yellowing of the skin and eyes), anemia, brain damage, mouth failure and even death, but it does not affect mother health.

In the United States, approximately 20,000 babies of Rh hemolytic disease are born each year. However, since the treatment of Rh hemolytic disease was available in 1968, the number of newborn babies suffering from Rh hemolytic disease has decreased significantly each year. But not all pregnant women who need preventative treatment can receive this treatment, so a small proportion of pregnant women still do not benefit from this technology. As a result, approximately 4,000 babies with Rh hemolytic disease are still born each year.

Causes of Rh blood group system

Most people in the population are Rh-positive blood types, with Rh antigen, a genetic protein in the name of red blood cells. Approximately 15% of whites and 7% of African Americans in the United States do not have Rh antigens, which is Rh-negative blood types. People with Rh-negative blood types do not have any health problems themselves, however if a woman is Rh-negative blood types, there is a risk of giving birth to Rh-hemolytic infants.

Rh blood group system prevention

To prevent Rh hemolytic disease, all children of women with Rh-negative blood group should have a Rh-blood test at birth. All Rh-negative mothers with Rh-positive children should be injected with a mixed blood Rh immunoglobulin 72 hours after delivery, which can prevent sensitization of more than 95% of Rh-negative women. However, some studies have shown that about 2% of pregnant women are sensitized before delivery. Therefore, in consideration of early sensitization, Rh immunoglobulin can be injected into pregnant women at 28 weeks of pregnancy and after delivery. Women with Rh-negative blood types should be injected with Rh immunoglobulin after natural abortion, ectopic pregnancy, induced abortion, or transfusion of Rh-positive blood. In addition, Rh immunoglobulin soap should also be injected after amniocentesis and fetal chorionic biopsy.

1. Discovery of Rh blood group system and distribution in the population In the search for new blood group substances, when red blood cells of the Rhesus monkey were repeatedly injected into rabbits, the rabbits developed an immune response. At this time, rabbits Antibodies (lectins) against rhesus erythrocytes are produced in the serum. The serum containing this antibody was mixed with human red blood cells. It was found that about 85% of white people's red blood cells can be agglutinated by this serum, indicating that these people's red blood cells have the same antigen as rhesus Therefore, it is called Rh-positive blood group; about 15% of people's red blood cells are not agglutinated by this serum, which is called Rh-negative blood group. This blood group system is called Rh blood group. Among the people of all ethnic groups in China, the Han and most other ethnic groups are Rh-positive, accounting for 99%, and Rh-negative persons, accounting for only 1%. However, in other ethnic minorities, Rh-negative people are more, such as 12.3% in the Miao and 15.8% in the Tatar.

2. The genotype and expression of the Rh blood group system The serum test suggested that the Rh blood group system on human red blood cells includes five different antigens, which are called C, c, D, E, and e. Theoretically, there are 3 pairs of alleles Cc, Dd and Ee controlling 6 antigens. However, in fact, no single anti-d serum was found, so d is considered to be a "resting gene", and d antigen is not expressed on the surface of red blood cells. Among the 5 antigens, the D antigen has the strongest antigenicity. Therefore, those that contain D antigen on red blood cells are usually called Rh-positive; those that lack D antigen on red blood cells are called Rh-negative.

3 The characteristics of Rh blood group and its significance in medical practice. The aforementioned ABO blood group pointed out that the lectin of the ABO system, which is a natural antibody, has been present in human serum from a few months after birth. However, there is no natural anti-Rh antibody in human serum. Only when Rh-negative people receive Rh-positive blood, anti-Rh antibodies are produced through humoral immunity. In this way, there is generally no obvious response after the first blood transfusion, but the antigen-antibody reaction occurs when the Rh-positive blood is re-transfused the second time or multiple times, and the Rh-positive red blood cells that are input are agglutinated.

Rh blood group system antibody characteristics

Another difference between the Rh system and the ABO system is the characteristics of the antibody. The antibodies of the ABO system are generally full antibodies IgM. The antibodies of the Rh system are mainly incomplete antibodies IgG, the latter molecules are more able to penetrate the placenta. Therefore, when a negative mother is pregnant with a positive fetus, the hourly red blood cells or D antigen of the positive fetus can enter the mother, and through the immune response, immune antibodies, mainly anti-D antibodies, are produced in the mother's blood. This antibody can enter the fetal blood through the placenta, and can cause the livelihood of the red blood cells of the fetus to agglutinate and lyse, resulting in hemolytic anemia in the newborn, which can cause fetal death in severe cases. However, generally only a large number of fetal red blood cells enter the mother during childbirth, and the antibody concentration in the mother's blood is slowly increasing, which usually takes several months, so the first pregnancy often does not produce a serious reaction. If Rh-negative mothers conceive Rh-positive fetuses again, at this time, high concentrations of Rh antibodies in maternal blood will pass through the placenta, destroying a large number of fetal red blood cells.

Clinical significance of Rh blood group system

Related to blood transfusion, if Rh-negative people enter Rh-positive blood for the first time, anti-Rh antibodies appear in the serum under the stimulation of Rh antigen, and transfusion reactions will occur when Rh-positive blood is re-infused later. It is related to pregnancy. For Rh-positive fetuses, due to the incompatibility of the fetus with the fetal blood type, the mother produces antibodies corresponding to the fetal red blood cell antigen, which enters the fetus through the placenta and causes hemolysis. Therefore, if a woman has a stillbirth multiple times and the baby dies from jaundice multiple times, the possibility of Rh blood group incompatibility should be considered.