Transfusion immunology

A 25-year-old female presents with significant haemorrhage secondary to a ruptured

ectopic pregnancy. Which blood component transfusion practice is MOST LIKELY to

cause harm?

a) Transfusion of A +ve packed red cells to an AB –ve recipient

b) Transfusion of A –ve packed red cells to an AB +ve recipient

c) Transfusion of AB +ve fresh frozen plasma to AB –ve recipient

d) Transfusion of B +ve cryoprecipitate to an O –ve recipient

e) Transfusion of AB –ve platelets to an O +ve recipient

Answer: A

Explanation

The issues here are ABO compatibility and rhesus D compatibility requirements of

various blood components and awareness of the risk of rhesus D isoimmunisation in a

Rh –ve woman of childbearing age. Cryoprecipitate need not be ABO or Rh compatible.

Fresh frozen plasma (FFP) must be ABO compatible but Rh compatibility is not

considered. Platelets should ideally be ABO and Rh identical, or at least compatible.

However, there is only a very low risk of any sort of reaction. If matching is not possible

due to scarce resources, ABO incompatible platelets are acceptable (with some exceptions),

but with the potential for reduced efficacy. In terms of red cells, the AB +ve

patient is the universal recipient and can be transfused any type if cross-matched,

identical-type red cells are not available. Type AB recipients may receive type A red

cells as the small amount of anti-B antibodies from the donor seldom causes a problem.

Haemolytic disease of the newborn occurs where maternal Anti-Rh-D antibodies

(produced in response to a previous sensitisation event in a Rh –ve mother) cross the

placenta and destroy foetal Rh +ve cells. The resultant foetal anaemia can have

disastrous consequences. This is why it is crucial that Rh –ve women are not transfused

Rh +ve components – red cells clearly carrying the greatest risk. We are accustomed to

using O –ve blood in an emergency but in fact for males over 16 or females beyond

childbearing, use of O +ve blood in an emergency is acceptable and indeed written

into the transfusion practice guidelines in some US centres.

References

McClelland DBL (ed) Handbook of Transfusion Medicine, 4th edn. UK Blood Transfusion

and Tissue Transplantation Services. London: TSO, 1997. Online at www.transfusion

guidelines.org.uk (Accessed 30 October 2009)

Serious Hazards of Transfusion (SHOT) website. Online at www.shotuk.org (Accessed

30 October 2009)

Serious Adverse Blood Reactions and Events (SABRE) webpage. Online at www.mhra.gov.uk

gov.uk (Accessed 30 October 2009)