RBC T activation and hemolysis in a neonatal intensive care population: implications for transfusion practice.
BACKGROUND
Reports of transfusion-associated hemolysis in infants with T-activated RBCs have led to the suggestion that infants should be screened and provided with low-titer anti-T blood components. T-activated RBCs react with the lectins Arachis hypogea and Glycine soja; variants of T (Th and Tx) and Tk also react with A. hypogea, but not G. soja. Although Tk is not a true variant of T, for the purposes of this study, all RBCs that are reactive with A. hypogea but are not reactive with G. soja are called "T variants."


METHODS
A prospective study was carried out to examine T and T variant activation and transfusion-associated hemolysis in a neonatal intensive care population and to determine if antibodies to T and T variant are detectable in donor plasma. A total of 2041 samples from 375 infants were tested for T and T variant activation utilizing a lectin panel. Three hundred donor plasma samples were tested for antibodies to T and T variant.


RESULTS
Forty-eight of 375 infants (12.8%) had T- and T-variant-activated RBCs. Of these, 13 of 48 (27%) developed at least one episode of sepsis and 9 of 48 (19%) developed necrotizing enterocolitis (NEC) at some point during their inpatient stay. T activation was not always temporally associated with the onset of NEC or sepsis. The remaining 26 of 48 (54%) were healthy infants receiving convalescent care in the neonatal intensive care units and showed no evidence of either NEC or sepsis. Twelve (of 375) additional infants (3.2%) who developed NEC and 100 (27%) who developed sepsis showed no RBC T activation. Twenty-three of 48 (48%) infants with T-activated RBCs received standard blood components, but no transfusion-associated hemolysis occurred. Donor plasma samples contained T but not T variant antibodies.


CONCLUSIONS
T variant activation of RBCs occurs in healthy neonates as well as in infants with NEC and sepsis, but T activation appears rare. Transfusion- associated hemolysis was not seen. The provision of specially prepared blood components for infants with NEC is unnecessary.
Boralessa
Harischandra
H
National Blood Service, Brentwood Center, Essex, United Kingdom. hari.boralessa@nbs.nhs.uk
Modi
Neena
N
Cockburn
Hazel
H
Malde
Ranjan
R
Edwards
Marilyn
M
Roberts
Irene
I
Letsky
Elizabeth
E
D000906:Antibodies / Q000097:blood*; D015295:Antigens, Tumor-Associated, Carbohydrate / Q000097:blood*; D001426:Bacterial Proteins / Q000097:blood* / Q000494:pharmacology; D016913:Blood Component Transfusion / Q000706:statistics & numerical data; D001782:Blood Donors; D001803:Blood Transfusion / Q000706:statistics & numerical data; D020345:Enterocolitis, Necrotizing / Q000097:blood / Q000201:enzymology / Q000382:microbiology; D004910:Erythrocyte Membrane / Q000737:chemistry* / Q000187:drug effects; D017707:Erythrocyte Transfusion / Q000009:adverse effects*; D005865:Gestational Age; D006461:Hemolysis; D006801:Humans; D007075:Immunoglobulin M / Q000097:blood*; D007231:Infant, Newborn; D007363:Intensive Care Units, Neonatal; D037102:Lectins / Q000378:metabolism; D008131:London; D009439:Neuraminidase / Q000097:blood* / Q000494:pharmacology; D019887:Peanut Agglutinin / Q000378:metabolism; D037121:Plant Lectins / Q000378:metabolism; D011446:Prospective Studies; D018805:Sepsis / Q000097:blood / Q000201:enzymology / Q000382:microbiology; D030262:Soybean Proteins / Q000378:metabolism; D014312:Trisaccharides / Q000097:blood*; D010835:Phytohemagglutinins
D000906:Antibodies; D015295:Antigens, Tumor-Associated, Carbohydrate; D001426:Bacterial Proteins; D007075:Immunoglobulin M; D037102:Lectins; D009439:Neuraminidase; D019887:Peanut Agglutinin; D037121:Plant Lectins; D030262:Soybean Proteins; D014312:Trisaccharides; C064068:Thomsen-Friedenreich antigen, cryptic; C028824:soybean lectin; D010835:Phytohemagglutinins; C016467:Thomsen-Friedenreich antigen; C025991:Thomsen-Friedenreich antibodies