Transfusion therapy in autoimmune hemolytic anemia

1
Transfusion therapy in autoimmune hemolytic anemia
??Warm autoimmune hemolytic anemia (WAIHA)
Patients blood
Clinical evidence of WAIHA
Transfer
Notify
Blood bank
Determination of patients RBC phenotype
Cross matching
Serologic evaluation positive antibody
screen autoantibody absorption
(time-consuming)
RBC autoantibodies
RBC alloantibodies Identify any
RBC alloantibodies (time consuming)
Coombs test
Select blood lacking the respective antigens
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Direct ( -) Clinical evidence of WAIHA
Direct () Indirect ( -)
Direct () Indirect ()
False positive a. 1/10000 normal persons b.
hypergammoglobulinemia c .medications d.
collection of samples from Iv lines
containing low ionic strength solutions
False negative a. IgA or IgM
autoantibodies b. low affinity IgG
autoantibodies c. low numbers of IgG
antibodies
Recently transfused patient
Antibodies elution
-

alloantibody autoantibody
autoantibody
Practical aspects of transfusion in WAIHA
Communication between clinican and the blood bank
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Risk of transfusion
1. Presence of the autoantidody complicates
pretransfusion testing and may prevent
accurate identification of coexisting
alloantibodies ? allantibody- induced
hemolytic transfusion 2. Autoantibody itself may
cause decreased survival of transfused cells ?
worsening hemolysis and clinical deterioration
Decision making
1. Patients clinical status 2. Potential benefit
of transfusion 3. Potential response to other
therapeutic modalities 4. Status of the serologic
evaluation and pretransfusion testing
Severe but stable anemia steroid therapy
Chronic stable anemia (poor response to
immunosuppressive therapy)
Acute fulminant hemolysis or progressively severe
anemia
Cardiac or cerebral dysfunction
Urgent transfusion before all the serologic
tests are completed
Periodic transfusion after completed serologic
tests
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1. Small quantities 1-2 units 2.
Tranfused slowly 1-2 units/4 hours
(except massive hemorrhage)
Warrant close observation
1. High-output cardiac failure (circulatory
overload) 2. Potential for hemolytic transfusion
reaction (Hb ?, Indirect bilirubin ?
GOT ?, LDH ?, haptoglobin ?)
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??Cold agglutinin disease (CAD)
Patients blood Transfer
Clinical evidence of CAD
Notify
Blood bank
Determination of patients RBC phenotype (prewarmi
ng techniques)
Serologic evaluation
Determined thermal amplitude
Identify coexisting RBC alloantibodies
Autoabsorption in the cold
37?
Cold agglutinin titration studies
Confirm the immunoglobulin isotype
alloantibodies
Cold autoantibodies
Perform cross matching at 37 ?
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Clinical condition suggests the need for
transfusion
1. In-line blood warmer 2. Place on warming of
the patient
Proceduces requiring systemic hypothermia
Warming of extracorporeal circuit
Warrant close observation 1. Potential for
hemolytic transfusion reaction
(infrequently) 2. High-output cardiac failure