Blood Bank Exam 5

Autoimmune hemolytic anemia is caused by what?

Autoantibodies

If you have autoantibodies, do you have autoimmune hemolytic anemia?

Not necessarily. They have to show immune mediated RBC destruction

If a person has AIHA, what would their test results look like for blood bank and other departments?

blood bank: + DAT, + auto control, + antibody screen with panagglutination, panreactive eluate

Other departments: low Hgb/Hct, low haptoglobin, high bilirubin, high retic count, high LDH

What causes autoantibodies?

Loss of suppressor T-cell function

What are some reasons for having a positive DAT?

-autoantibody

-alloantibody

-maternal antibody

-drug related process

Difference between benign and pathologic CAA

benign: thermal range below 20 - 24 C, Titer < 64, marginally enhanced with albumin, anti-I or anti- H

pathologic: may be reactive >30 C, titer > 1000, strongly enhanced by albumin, Anti-I

If you have an ABO discrepancy with a CAA, how do you fix it?

-37 degree backtype

-Prewarm technique

If you have panreactivity from a CAA on an ABID, how do you fix the problem?

(Hint* answer changes if the patient has been transfused)

If the patient has not been transfused, you do a prewarm. If they have been transfused, use RESt.

What do you do if your autocontrol comes out positive?

Perform a DAT

When do you use a alloadsorption vs an autoadsorption?

auto = patient has NOT been transfused and you have enough cells

allo = patient has been transfused or you do NOT have enough cells

What are two pathological CAAs?

CHD and PCH

defining characteristics of CHD

-found in old people

-associated with pneumonia or mono

-anti-I

-chronic

-extravascular/ intravascular hemolysis

-IgM

-titer > 1000

-fix by avoiding the cold

Defining characteristics of PCH

-seen in children

-follows viral infections

-acute

-intravascular hemolysis

-IgG (biphasic)

-anti- P

- < 64 titer

- + donath-landsteiner test

- treat by fixing underlying cause

What is the most common autoantibody?

Warm autoantibodies (70%)

What are characteristics of WAAs?

-IgG

-react best at AHG

-enhanced by enzymes

-antibody panel looks positive in the AHG column for everything including auto control

-eluate will be positive for everything

What are some transfusion consideration when working with WAAs?

-only transfuse if clinically indicated

-transfuse blood that is ABO, Rh and Kell compatible

Drug Adsorption:

drug involved

process

DAT results

eluate results

hemolysis types

-penicillin, cephalosporins

-drug binds RBC and is recognized by antigen

-IgG +++, C3 ++

-ABSC neg, eluate neg

-extravascular

Immune Complex:

drug involved

process

DAT results

eluate results

hemolysis types

-Quinine, phenacetin

-AB/drug complex binds to RBC

-IgG +, C3 +++

-ABSC neg, eluate neg

-intravascular

Induction of autoantibody (methyldopa):

drug involved

process

DAT results

eluate results

hemolysis types

-methyldopa

-alters membrane or down regulates normal immune suppression

-IgG +++, C3 +

- ABSC pos, eluate pos

-extravascular

Membrane Modification:

drug involved

process

DAT results

eluate results

hemolysis types

-cephalosporin

-drug coats RBC

-IgG+, C3+, IgM+

-ABSC neg, eluate neg

What vitals must be measured pre, during, and post transfusion?

-temp

-blood pressure

-pulse

Difference between acute and delayed reactions?

acute - less than 24 hours

delayed - greater than 24 hours

What are the three febrile acute transfusion reactions?

-AHTR

-TAS

-FNHTR

What are the two allergic acute transfusion reactions?

mild and severe

What are the two pulmonary transfusion reactions?

-TACO

-TRALI

What is the transfusion reaction we are most worried about?

Acute hemolytic transfusion reactions

What is the only drug induced hemolytic anemia that causes intravascular hemolysis?

Immune complex

If someone is on methyldopa, what will their test results look similar to?

it will look like a WAA

How do you tell the difference between a mimicking anti-e autoantibody, and an actual anti-e antibody?

phenotype the patient. If it is an actual anti-e they will be e negative for the antigen

What is the work flow for a WAA?

-Type and screen

-screen is positive

-ABID

-panreactive ABID including auto ctrl

-DAT

-IgG positive

-eluate

-panreactive eluate

-adsorption

What is the work up for a CAA?

-Type and screen

-type discrepancy

-short cold panel

-panreactivity

-do 37 degree backtype

-if that doesnt work, prewarm

-If ABSC positive, do ABID

-ABID panreactive

-DAT

-IgG neg

-prewarm

Can you do a blood type using RESt plasma?

No. It reduces the titer of anti-B

What cells are need to perform a donath-landsteiner test?

-O type

-P+

-50% cell suspension

If a donath landsteiner test needs to be done, how is the sample collected?

-drawn in red top

-transported at 37 C to blood bank immediately

Acute Hemolytic Transfusion Reaction:

cause

temp

blood pressure

pulse

symptoms

blood bank work up

hemolysis

-caused by ABO incompatibility

-temp increases

-pulse increases

-blood pressure decreases

-pain, hemoglobinuria

-DAT positive

-intravascular hemolysis

Transfusion Associated Sepsis:

cause

temp

blood pressure

pulse

blood bank work up

-contaminated products

-temp increases at 2 C

-pulse increases

-blood pressure decreases

- don't see anything, culture only of medical director indicates

Febrile nonhemolytic transfusion reaction:

temp

blood pressure

pulse

blood bank work up

-temp increases

-blood pressure and pulse can go either way

-nothing in the workup

Mild allergic reaction

Look for a rash, do a clerical work up, treat with benadryl then you are done

Severe allergic reaction:

SPO2

Respiration

temp

pulse

blood pressure

Blood bank workup

-spo2 decreased

-respiration increased

-temp maybe increase

-pulse increase

-blood pressure maybe increase

-nothing in workup

How do you prevent a severe allergic reaction during transfusion from happening?

-give washed cells

TACO

temp

pulse

blood pressure

spo2

respiration

caused by

symptoms

treatment

temp no change

pulse increase

blood pressure variable

spo2 decreases

respiration increases

caused by circulatory overload

symptoms jugular distention, wheezing, coughing, pulmonary edema

responds to diuretics

TRALI

temp

pulse

blood pressure

SPO2

respiration

symptoms

treatment

temp variabel

pulse increases

blood pressure increase

SPO2 decreases

respiration increases

symptoms coughing, wheezing

treatment oxygen therapy

What is the number one cause of transfusion fatalities in the US?

TRALI

What 3 transfusion reactions are considered to by immune responses?

DHTR

AHTR

Severe allergic reaction

What is a key indication you have graft vs host disease?

maculopapular rash (starts in the core and extends outwards toward extremities)

What is the only delayed reaction where you will see something on the blood bank bench in the workup?

Delayed hemolytic transfusion reaction

How do you prevent TA-GVHD?

use irradiated units

What is the most common antibody associated with Post Transfusion Purpura?

anti-HPA-1a

What patients tend to have problems with iron overload?

sickle cell, beta thalassemia, and blackfan diamond anemia

What are side effects of massive transfusions?

hypothermia

hyperkalemia

citrate toxicity

What antigens are warm autoantibodies directed toward?

High prevalence antigens

What antigens are cold autoantibodies directed toward?

I,i, H, I/H combo

What percent of AIHA are caused by warm autoantibodies?

70%

What antibody to warm autoantibodies usually mimic?

Anti-e

What reactivity would you expect in an antibody screen and panel for a cold auto patient?

Reactivity at IS that decreases at 37C and disappears at AHG phase. Reactivity stronger at RT and 4C

What reactivity would you expect in an antibody screen and panel for a warm auto patient?

Panagglutination at AHG phase, positive autocontrol

What reagents/tests can we use to remove a warm autoantibody from a patient's sample when it is interfering with testing?

Adsorption – Allo or Auto

With PCH (Paroxysmal Cold Hemoglobinuria), what antibody is involved and what are characteristics of it?

• Anti-P, biphasic hemolysin.

• Attaches to complement at lower temperatures (extremities), then causes hemolysis as it moves to warmer temperatures (The
  heart, core).

• Donath Landsteiner test to confirm presence.

Which drug adsorption method is associated with a drug induced positive DAT?

Cephalosporin – causes changes to RBC membrane
Quinidine - most associated with the immune complex mechanism of drug→ induced positive DAT

What are signs/symptoms of Cold Hemagglutinin Disease?

Anemia, Acrocyanosis of the hands and feet, Raynaud's phenomena, Agglutination of red cells in capillaries.

What is the most important step in transfusion?

Accurately identify the donor unit and recipient

What is an acute transfusion reaction?

A reaction with signs or symptoms that occurs within 24 hours of a transfusion.

What is a delayed transfusion reaction?

A reaction with signs or symptoms presenting after 24 hours of
a transfusion.

What are the acute transfusion reactions?

• Acute hemolytic

• Transfusion associated sepsis

• Febrile non-hemolytic

• mild allergic

• severe allergic

• TACO

• TRALI

What are the delayed transfusion reactions?

• Delayed hemolytic

• Transfusion associated graft vs. host

• Post transfusion purpura

• Iron overload

Acute hemolytic syptoms

• Fever, shock, hypotension
• Abdominal, flank, or back pain
• Pain at the transfusion site
• Feeling of impending doom
• Hemoglobinemia, Hemoglobinuria
• Renal failure
• Diffuse intravascular coagulopathy

Delayed hemolytic symptoms

• Slight fever
• Decreasing hemoglobin and hematocrit
• Platelet refractoriness with bleeding

Febrile Nonhemolytic symptoms

• Chills, nausea or vomiting
• Tachycardia
• Increase in BP
• Tachypnea
• Occasionally shaking chills is initial symptom

Mild Allergic symptoms

Redness, itching, hives (urticaria), fever (may or may not happen).

Severe allergic

Anaphylaxis – coughing, dyspnea, nausea, vomiting, hypotension, skin flushing, abdominal cramps, diarrhea, shock, loss of consciousness

Transfusion Associated Circulatory Overload (TACO) symptoms

• Respiratory distress (wheezing, coughing)
• Headache
• Chest tightness
• Hypertension - Jugular vein distention
• Elevated central venous pressure, elevated pulmonary wedge pressure

Transfusion Related Lung Injury (TRALI)

• Respiratory distress (wheezing, coughing)
• Headache
• Fever
• Chest tightness
• Hypotension
• Cyanosis

Post Transfusion Purpura (PTP) symptoms

Thrombocytopenia, hematuria, bleeding

What is the most common transfusion reaction type reported in the blood bank?

Febrile reactions

Which type of transfusion reactions happen immediately?

Acute

Can a brisk primary immune response, or an anamnestic immune response to a blood group antigen, both lead to a delayed transfusion reaction?

Yes

Can transfusion reactions other than febrile non hemolytic present with a fever?

Yes

Which transfusion reaction is the only one where no workup is required?

Mild allergic with hives only.

What is post transfusion purpura usually caused by?

anti-HPA-1a

Which transfusion reaction is non-immune?

TACO

What tests and checks need to be done when a transfusion reaction report and sample are received?

Clerical check, check for hemolysis, ABORh and DAT

If a patient has had multiple febrile non-hemolytic transfusion reactions, what kind of product do we recommend for future transfusions?

Leukocytes reduced

If a person has an anaphylactic transfusion reaction, what kind of
products do we recommend for future transfusion?

Washed products