“Based on all the studies published to date, we can not determine incidence of transfusion-associated necrotizing enterocolitis (TANEC),” Dr. Parkesh S. Shah from University of Toronto, Toronto, Ontario, Canada told Reuters Health by email. “There are a lot of unanswered questions with regards to this condition.”
Dr. Shah and Dr. Adel Mohamed performed a systematic review and meta-analysis of the association between recent packed red blood cell transfusion and the development of necrotizing enterocolitis. Their review was based on 12 published studies including 4857 neonates.
Meta-analysis of 5 studies reporting unadjusted estimates of exposure to transfusion in the previous 48 hours found a 3.91-fold increased risk of necrotizing enterocolitis after recent transfusion.
Similarly, meta-analysis of 4 studies reporting adjusted estimates found a 2.01-fold increased risk of necrotizing enterocolitis after recent transfusion.
Factors associated with TANEC included lower gestational age, lower birth weight, patent ductus arteriosus, and being ventilated at the time of diagnosis.
Neonates with TANEC were 88% more likely to die than were neonates with NEC not associated with transfusion, and the rate of intraventricular hemorrhage of at least grade 3 was significantly higher among TANEC infants (38%) than among infants with NEC not associated with transfusion (17%)(P<0.0001) in one study.
Withholding feedings during transfusions may reduce the rate of TANEC, but the data were insufficient to determine this with confidence.
“This analysis does not underscore the fact that there are many cases of NEC that are not associated with transfusion,” the researchers note, “and many transfusions happen in preterm neonates who are not linked to NEC within 48 hours. Thus, this analysis does not claim to have established a cause-effect relationship but only suggests an association.”
“There is an urgent need for a prospective study to look at all transfusions and establish incidence of TANEC,” Dr. Shah said. “Future studies assessing actual rates of TANEC, etiological factors for TANEC, outcomes of TANEC neonates and strategies to prevent TANEC are needed.”
“We are in the process of planning a prospective study looking at all transfusions in preterm infants to assess the age at transfusion, type of transfusion (emergency un-matched or semi urgent matched), age of transfused blood, hematocrit pre and post transfusion and hematocrit of the donor blood, rate of transfusion, characteristics of donor blood in form of infective agents, use of diuretic after transfusion, preexisting concern regarding intestinal motility, feeding during transfusion, rate of feeding, duration of NPO, minor group incompatibility, and if funding permits assess cytokines alteration pre and post transfusion,” Dr. Shah added. “This study will be able to highlight incidence and some possible etiological factors for TANEC.”