SBB 561 Delayed Transfusion Reactions

• Fever
• Declining Hgb (extravascular hemolysis)
• mild Jaundice

• Kidd
• Kell
• Duffy
• c
• D
• E

Immune response to foreign antigens on RBC, or WBC and platelets (HLA).

DAT may become postive before antibody levels are detectable. 

May need to elute antibody off RBC's to identify

XM may still be compatible initially (when titers are still too low)

• Not fully known - 
• Initiated by alloreactive donor T cells recognizing host histocompatibility antigens
• Donor lymphs engraft in the recipient, proliferate, and attack host tissue.

• 10-12 days post transfusion:
• Fever, dermatitis/erythroderma, hepatitis, enterocolitis, pancytopenia, & immunodeficiency

• Degree of HLA similarity
• immunocmepetent heterozygous HLA haplotype recipient of a donor who is homozygous for an HLA haplotype and component contains many T-lymphs. 
• Presence & degree of recipient immunodeficiency. 
• jNumber of transfused lymphs cappable of multiplying

• Irradiation: Minimum 2500 cGy to midplane of container and 1500 cGy to other parts.
• This prevents T lymphs of replication and at the same time not destroying cellular function.

• Cellular components for intrauterine transfusions
• At risk patients
• Cellular transfusion between blood relatives
• Transfusion of HLA selected products