Blood group testing methods

Article written by BSCKII.ThS. Le Thi Na, Laboratory Department, Vinmec Times City International General Hospital

Blood group is determined by the presence of antigens on the surface of red blood cells and antibodies in the serum. When these two components meet, a specific agglutination reaction occurs.
People with type A blood have A antigens on the surface of their red blood cells, anti-B antibodies in their serum.
People with type B blood on the surface of red blood cells have B antigens, and anti-A antibodies in their serum. Blood group AB has A and B antigens on the surface of red blood cells, and no antibodies in the serum.
People with type O blood have no antigens on the surface of red blood cells, there are anti-A and anti-B antibodies in the serum.
Rh blood group has antigens only but no natural antibodies, people with RhD-positive blood group have D antigens on the surface of red blood cells, people with RhD negative blood group do not have D antigens on the surface of red blood cells.

When there is an indication for blood transfusion or there is a risk of blood transfusion:
When anemic or in preparation for surgery, the procedure is likely to cause a lot of blood loss; Testing to select appropriate blood units when dispensing blood for transfusion; When registering to donate blood, donate tissues and organs of a woman during pregnancy for the purpose of controlling the risk of causing mother-child blood group incompatibility; When it is necessary to determine the bloodline; Healthy people should know their blood type for convenience when donating or receiving blood.

3.1 Manual method There are two manual methods including: Blood grouping on the plate and blood grouping in the test tube.
The advantages of manual methods are simple, easy to do, and cheap.
Disadvantages: Manual method is prone to technical errors, confusion about administrative procedures, depends on skills and qualifications of technicians.

3.2 Automated Methods There are two automatic methods: Semi-automatic Gelcard blood grouping and Gelcard blood grouping on a fully automated machine.
Advantages of the automated method: It is a technique with high sensitivity and specificity, giving clear agglutination results. In particular, blood grouping by Gelcard on fully automatic machines brings outstanding advantages such as:
About the process: It is a technique with steps to perform the process fully automatically, minimizing direct intervention. laboratory staff input into the analysis process to minimize the risk of errors. About samples for testing: Small number of samples (1 tube of EDTA anticoagulant, instead of 1 tube of EDTA and 1 tube of serum). Regarding sample analysis: simultaneously performing different tests on the same sample in one test, having random access, continuously in batches or each sample, with a priority position for testing. Emergency testing helps to optimize the testing process and shorten the time to return results.

Blood group testing should be done in reputable, quality hospitals and medical facilities for accurate results.
At Vinmec International General Hospital, it is equipped with a fully automatic blood group testing machine using Gelcard, the test quality is up to ISO 15189: 2012. The team of doctors is well-trained and specialized. Deeply, highly qualified and experienced to help diagnose and provide effective treatment regimens.
To register for testing at Vinmec International General Hospital, you can contact the nationwide Vinmec Health System Hotline, or register online HERE.