ABO antigen incompatibility appears to be the most frequent cause of hemolytic disease of the fetus and newborn (HDFN), leading to exchange transfusions during the neonatal period, according to a recently published study in the Iranian Journal of Medical Sciences.
Hyperbilirubinemia is a medical term that describes excessive bilirubin accumulation in the blood. Bilirubin is a product of red blood cell (RBC) degradation, which is usually found in the blood at low levels; in normal conditions, bilirubin is metabolized by the liver and excreted from the body through the intestines. Hyperbilirubinemia causes yellow pigmentation of the skin, which is known as jaundice.
Furthermore, hyperbilirubinemia can lead to a complication known as kernicterus in newborns. In this condition, excessive bilirubin crosses the blood-brain barrier, producing permanent neurological damage. Affected newborns are usually lethargic, weak, and flaccid, and they eventually fail to achieve developmental milestones as they grow up.
There are many causes of hyperbilirubinemia in the neonatal period, including liver diseases such as Gilbert syndrome, which prevents bilirubin from being degraded in the liver, infections leading to sepsis and excessive RBC destruction (hemolysis). HDFN is a leading cause of hemolysis in the prenatal and neonatal period and must be ruled out in neonates with jaundice.
One of the most effective methods for hyperbilirubinemia management in newborns consists of exchange transfusions. The authors aimed to determine which risk factors were associated with a higher need for exchange transfusions in newborns.
The study analyzed data from 377 transfusions received by 329 patients; results showed that the most common cause of transfusion was a deficiency of the enzyme G6PD, which is vital for the correct functioning of RBCs, followed by prematurity. HDFN due to ABO incompatibility was the third most frequent cause, representing 7% of the studied cases.
“Although the rate of ET occurrence has decreased, it seems necessary to consider different risk factors, and appropriate guidelines for early identification and management of neonates at risk of ENH should be developed,” the authors concluded.
