Autoagglutination, rouleaux formation, and various ABO blood grouping errors can lead to inaccurate blood typing results, potentially causing clinical complications. It is essential to identify the causes of false ABO blood grouping results and apply proper ABO grouping quality control measures to avoid these issues, which may include false positive reactions in blood typing or other ABO grouping mistakes.
Autoagglutination
Autoagglutination occurs when IgM autoantibodies in the patient's serum react at room temperature, causing unintended agglutination of red blood cells. This often results in ABO blood grouping errors, especially when autocontrol is not utilized, leading to incorrect blood typing, such as misidentifying the blood type as AB. To prevent such ABO grouping mistakes, autocontrol should always be performed. If autocontrol shows agglutination, the cell grouping should be repeated after washing the red cells with warm saline, and serum grouping should be conducted at 37°C.
Rouleaux Formation
Rouleaux formation can be mistaken for agglutination, which can cause significant ABO grouping laboratory errors. This occurs when red blood cells adhere together in a stack-of-coins formation, often due to high levels of fibrinogen, immunoglobulins, or plasma expanders like dextran. Unlike true agglutination, rouleaux can be dispersed by adding normal saline during serum grouping, thereby preventing false positive reactions in blood typing.
False-Negative Results Due to Inactivated Antisera
Inactivated antisera can lead to false ABO blood grouping results, often manifesting as false-negative outcomes. To ensure proper ABO grouping quality control, antisera should be stored at 4°C to 6°C. Antisera that are left at room temperature for extended periods lose their potency, leading to inaccurate blood typing results. Proper storage is crucial to prevent these ABO grouping laboratory errors.
Age-Related Factors
Age is another factor that influences the accuracy of ABO blood grouping. Infants typically begin producing ABO antibodies between 3 and 6 months of age, meaning serum grouping before this age often results in false ABO blood grouping results. Similarly, elderly individuals may have lower antibody levels, leading to potential errors. Awareness of age-related factors is vital for minimizing ABO grouping mistakes and ensuring reliable results.
By understanding the causes behind these ABO blood grouping errors and implementing effective ABO grouping quality control, laboratory professionals can minimize the risk of false positive reactions in blood typing and improve the overall accuracy of blood typing procedures.