01Rh Blood Group System Overview
Rh blood group system, meaning Rhesus Macacus blood group system, is a human blood group system, there are negative and positive. When a D blood group substance (antigen) is present on a person's red blood cells, it is called Rh-positive, indicated by Rh(+); when the D antigen is lacking, it is Rh-negative, indicated by Rh(-). Most people are positive and Rh negative less, hence the name panda blood. The Rh system is the most complex system in the red blood cell blood group, second only to the ABO system, and 54 Rh antigens have been discovered, of which D antigen is the most powerful. Antigens D, C, c, E and e in the Rh blood group system are the most important in the clinic, and their strength and weakness order is D>E>C>c>e.
Data show that the big data of accidental antibody screening of Chinese transfusion patients shows that among the 14095 accidental antibodies, rh system antibodies are 9589 cases, accounting for about 68%; in 718 cases of antibody-specific hemolytic transfusion reactions, about 85% are caused by Rh system antibodies.
Individuals with Rh antigen-negative are stimulated by the corresponding antigen to produce immune alloant antibodies, namely anti-D, anti-C, anti-c, anti-E, anti-e, anti-e, which can clinically cause neonatal hemolysis (HDFN) and hemolytic transfusion reactions.
The discovery of Rh blood type is very important for more scientific guidance of blood transfusion and further improvement of experimental diagnosis of neonatal hemolytic disease and maintenance of maternal and infant health.
02 Rh blood group classification clinical application cases
Application cases of Rh blood group homotype infusion in clinical practice:
Patient, female, 58 years old. Admission to multiple fractures of the right lower extremity open
Blood type: positive for RhD O
Infusion of 42 units of erythrocytes within 18 days of admission
issue:
After 19 days, the patient had a transfusion reaction, and the patient's blood sample was identified as a direct antibody and a specific antibody, and the results were: direct antibody (+), specific antibody identification: anti-E/anti-c.
Solution:
Laboratory consultation, confirmed as a delayed hemolytic transfusion reaction caused by Rh incompatibility, and the patient's blood sample was tested for Rh blood group classification, the result was CCee (that is, E and c antigen negative, analyzed as the previous blood transfusion, because the patient and the blood donor were not tested for Rh typing, in the Rh blood group classification random transfusion, the patient was injected with positive blood of E antigen and c antigen, stimulating the patient to produce -E antibodies and -c antibodies, combined with the corresponding antigens, and a hemolytic transfusion reaction occurred), Symptomatic management and Rh-conjugated (CCee) infusions are recommended.
Results: The patient was given Rh-convalency (CCee) blood transfusion, the transfusion symptoms were alleviated, and the patient was eventually discharged from the hospital after external fixation stent with multiple fractures of the right lower extremity
03 Advantages of micro-column gel method for blood type measurement
(1) Optimized the interpretation mode: from the plane recognition under the traditional microscope to the stereoscopic naked eye interpretation, eliminating the subjective misreading factor.
(2) High sensitivity: The micro-column gel card method is higher than the traditional methodology in terms of sensitivity, which reduces the missed detection rate of weak antibodies.
(3) The results can be stored for a long time: if necessary, the results can be taken for permanent preservation, reducing the possibility of medical disputes.
(4) Automation: Automated operation is realized by equipping with fully automatic blood group instruments, which reduces the workload of clinical departments while improving efficiency and accuracy
Compared with the traditional blood group detection method, the results of the micro-column gel method are clear and easy to interpret, the accuracy and sensitivity are high, and the standardized sampling and standardized operations eliminate the interference of human factors in the traditional methods.
Clinical significance of 04 Rh blood group typing test
1) Prevent hemolytic transfusion reactions caused by the Rh blood group system
If there is an Rh antibody in the plasma of the recipient, after transfusion of blood containing the corresponding antigen, it will cause a severe hemolytic transfusion reaction, which can lead to death.
2) Prevent hemolysis in newborns caused by Rh-positive red blood cells
If there is Rh antibody in the plasma of pregnant women, when the pregnant Rh blood type does not cooperate with the fetus, the Rh antibody of the IgG class can enter the fetus through the placenta, destroy the red blood cells of the fetus with corresponding antigens, and cause neonatal hemolytic disease.
At this stage, the detection of D antigen in various hospitals has been fully launched, and the homotype of ABO and RhD has been realized, which has greatly reduced the frequency of anti-D production; However, testing for C, E, c, and e antigens is not widespread, and Rh E/e/C/c-negative patients who receive blood containing the corresponding antigen can stimulate the body to produce corresponding irregular antibodies; when the patient receives blood containing this antigen again, it can cause a delayed hemolytic transfusion reaction.
At present, most European and American countries and China's more economically developed areas have routinely carried out Rh antigen typing testing for blood donors, and China's current health administrative regulations only take RhD as a mandatory item. According to the needs of hospital patients and local blood donors, the department of blood transfusion of our hospital has carried out RH antigen classification testing, Rh blood group antigen identification can prevent women with fertility requirements, long-term blood transfusion and other special groups of people due to the transfusion of Rh blood group incompatibility of rh blood cell Rh antibody resulting in hemolysis (newborn), reduce adverse transfusion reactions, to achieve accurate blood transfusion, has high clinical significance.