ABO Incompatibility

ABO incompatibility is a common form of blood type mismatch that occurs when a person with one type of blood receives a blood product that contains another type of blood [1]. The four primary blood types – A, B, AB, and O – are classified based on the presence of specific antigens on the surface of red blood cells. When a person receives blood containing antigens their body doesn’t recognize, their immune system may react, leading to ABO incompatibility [2].

Risk Factors

Blood Transfusion

ABO incompatibility can occur in the context of a blood transfusion when the blood types of the donor and recipient do not match. The following table details the compatibility of different blood types in transfusions:

Pregnancy

Another risk factor is maternal-fetal ABO incompatibility, which arises when a pregnant woman and her unborn baby have different blood types [4]. This can lead to hemolytic disease of the newborn (HDN), although this is much less common with ABO incompatibility than with Rh incompatibility [5].

Symptoms and Complications

In the event of a blood transfusion reaction due to ABO incompatibility, the symptoms can include:

• Fever and chills
• Back or chest pain
• Nausea or vomiting
• Blood in urine

The complications of ABO incompatibility can range from mild to severe, and may include:

• Hemolytic reaction, where the body destroys the transfused blood cells
• Kidney failure, due to hemoglobin released from destroyed blood cells blocking the kidneys
• Disseminated intravascular coagulation (DIC), a severe complication where small blood clots form throughout the body, potentially leading to organ failure

Diagnosis and Treatment for ABO Incompatibility

Diagnosis typically involves laboratory testing to detect unexpected antibodies in the patient’s blood and to determine the patient’s blood type. Further investigations, such as a direct antiglobulin test (DAT), might be required in cases of maternal-fetal ABO incompatibility.

Treatment for ABO incompatibility involves supportive care to manage symptoms and prevent complications. For transfusion reactions, the transfusion is immediately stopped, and medications are given to manage symptoms. In severe cases, dialysis might be necessary to help the kidneys filter the blood.

Clinical Research and Advances

With advances in the medical field, understanding of ABO incompatibility has improved, as well as the strategies to deal with it. Current research is focusing on reducing the risk of hemolytic disease in newborns due to ABO incompatibility and developing more efficient and safer methods of blood transfusion.

Hemolytic Disease of the Newborn (HDN)

One significant focus of research has been the management of hemolytic disease of the newborn (HDN). When it occurs, HDN due to ABO incompatibility is usually mild, and the affected infants recover with little to no treatment. However, in rare cases, HDN can lead to severe jaundice, anemia, and even death. Current research aims to identify babies at risk early so that intervention can begin as soon as possible.

Prevention

ABO incompatibility can be largely prevented by careful blood typing and cross-matching before blood transfusion. In pregnancy, maternal-fetal ABO incompatibility can’t be prevented, but its impact can be mitigated through early detection and careful monitoring of the newborn for signs of HDN.

Future Perspectives

Looking towards the future, there is promising research into the creation of universally compatible blood. Scientists are studying enzymes that can remove the antigens from the surface of red blood cells, effectively turning all blood into type O, which can be received by any patient. Such an innovation would virtually eliminate the risk of ABO incompatibility in the context of transfusion.

Conclusion

ABO incompatibility, though a serious condition, is largely preventable with careful blood typing and matching. Its impact in maternal-fetal contexts can also be minimized with careful monitoring. As medical practices continue to improve, the risk associated with ABO incompatibility should continue to decrease.

Suggested Article

Bombay Bloog Group
Rh Factor or Rh Blood Group
ABO Blood Group System

References

[1] Dean, L. (2005). “Blood Groups and Red Cell Antigens.” National Center for Biotechnology Information, U.S. National Library of Medicine.

[2] Stowell, C. P., & Stowell, S. R. (2019). “Biologic roles of the ABH and Lewis histo-blood group antigens Part I: Infection and immunity.” Vox Sanguinis, 114(6), 426–442. https://doi.org/10.7554%2FeLife.65658

[3] “Blood Types.” (2022). American Red Cross.

[4] Christensen, R. D., Lambert, D. K., & Henry, E. (2013). “Initial hospital management of newborns with a positive direct antiglobulin test (DAT).” Clinical Pediatrics, 52(10), 903–908.

[5] Moise, K. J. (2008). “Management of rhesus alloimmunization in pregnancy.” Obstetrics and Gynecology, 112(1), 164–176.