Premature newborns that develop the medical condition called necrotizing enterocolitis (NEC), and have the AB blood type are nearly three times as likely to die from it as preemies with other blood types.

Doctors at Loyola University Medical Center (Maywood, IL, USA) examined records of 276 preemies in their neonatal intensive care unit (ICU) who suffered severe NEC during the last 24 years. Preemies often require multiple blood transfusions. Neonatal ICUs typically give Type O, the universal donor type, but this practice may inadvertently cause an enhanced immune reaction. This reaction, in turn, could be a reason why AB babies who develop NEC have a higher mortality.

The investigators found that AB preemies were 2.87 times more likely to die from NEC than babies with other blood types were. The significant difference in survival within the group of AB neonates is not only due to the disproportionate frequency of their demise (43%), but also to their short survival times. NEC likely involves several factors, including a decrease in blood flow to the bowel, infection, mechanical injury, and abnormal immune response. NEC occurs when the lining of the intestinal wall dies and tissue falls off. Most cases of NEC are mild to moderate and can be successfully treated with antibiotics. However, in severe cases, a hole can develop in the intestine, allowing bacteria to leak into the abdomen and causing a life-threatening infection.

The investigators suggested it may be prudent to change transfusion practices so that preemies receive their specific blood types, rather than the universal donor Type O. Jonathan Muraskas, MD, senior author of the study said "Although this will likely not eradicate NEC, it is an easily modifiable factor that may help to prevent those cases of NEC that develop in relation to the transfusion of blood products". The study was published on November 17, 2011, in the Journal of Perinatology.

Related Links:
Loyola University Medical Center