MLT GlobeBlood Banking: Transfusion reactions – page 3
51 Blood Banking MCQs on Transfusion reactions with answers and explanations.
Acute respiratory distress develops 2 hours after plasma transfusion. Which finding favours TRALI rather than TACO?
TRALI is non-cardiogenic lung injury and often presents with fever and hypotension. TACO usually shows hypertension, raised natriuretic peptides and responds to diuretics.
After stopping a transfusion because of a suspected reaction, the IV line should be:
The venous access is kept open with normal saline (through a new giving set) so fluids and drugs can be given if the patient gets worse.
Serious complications of an acute hemolytic transfusion reaction include:
Complement activation and cytokine release in acute intravascular hemolysis can cause shock, DIC and acute kidney injury.
Mild allergic (urticarial) transfusion reactions are mainly caused by:
Soluble substances in donor plasma bind recipient IgE on mast cells and basophils, releasing histamine and causing hives and itching.
Deglycerolised (frozen-thawed-washed) red cells are virtually free of plasma. Which recipient benefits most from this property?
Removing plasma proteins avoids anaphylaxis in patients with anti-IgA. Such cells supply no clotting factors or platelets.
A patient has hemoglobinuria after a group A unit was given to a group O patient. The post-transfusion DAT is negative. The best explanation is:
In severe intravascular hemolysis, coated donor cells may be lysed quickly, leaving no sensitized cells to detect. A negative DAT therefore does not exclude an acute hemolytic reaction.
Two weeks after transfusion, a patient has a new anti-Jkb and a positive DAT, but hemoglobin is stable and there are no signs of hemolysis. This is best classified as:
A new alloantibody with a positive DAT but no clinical or laboratory hemolysis is a delayed serologic transfusion reaction. A delayed hemolytic reaction requires evidence of hemolysis.
A patient with normal IgA has anaphylaxis during plasma transfusion. Deficiency of which plasma protein, with antibodies to it, is a known cause, especially in East Asian patients?
Haptoglobin deficiency with anti-haptoglobin antibodies is a recognized cause of transfusion anaphylaxis, mainly in East Asian populations. It is an alternative to IgA deficiency.
Which laboratory finding may be seen transiently soon after TRALI?
Neutrophils are sequestered in the lung, so a sudden transient drop in white cell count can occur. A high BNP suggests TACO rather than TRALI.
Why can an immunocompetent patient develop TA-GVHD after receiving blood from a relative?
If the donor is homozygous for an HLA haplotype the recipient also carries, the recipient sees donor lymphocytes as self and does not reject them. The donor cells then attack the recipient.
A patient with sickle cell disease is transfused. One week later, hemoglobin is lower than before transfusion and reticulocytes have fallen. What is the most likely diagnosis?
In hyperhemolysis, both donor and the patient's own red cells are destroyed, so hemoglobin falls below the pretransfusion level. More transfusion can worsen it; immunosuppression is used.