A child is admitted to the ED department with a viral infection. The patient's Donath-Landsteiner test is positive. The patient's diagnosis is most probably:
C. PCH
A specimen is sent to the Transfusion Service for testing on a patient with PCH. That DAT on the patient is positive for:
D. C3
The patient with PCH and a positive DAT for C3 has a positive antibody screen with a specifity of:
D. anti-P
A 30-year-old female is admitted with anemia of undetermined origin. A type and cross was received in the Transfusion Servce. The patient is in the computer system as an A neg and states she has no history of transfusion or pregnancy. The following are her results using tube testing:
IS 37C IAT
Screening Cell I 0 0 3+
Screening Cell II 0 0 3+
Autocontrol 0 0 3+
4 donor units 0 0 3+
The antibody panel resulted 3+ for all cells at IAT. The next step to find compatible blood would be:
B. Perform warm autoabsorption
A patient diagnosed with mycoplasma pneumoniae. The patient is also exhibiting some hemolysis and a type and screen is sent to the Transfusion Service. The specimen has a positive antibody screen. What antibody would you expect to be exhibited in the patients plasma?
C. Anti-I
A patient has a life threatening anemia due to warm autoantibodies. The patient's serum was 2+ at IAT with cells on a routine panel. A technique that would be beneficial to preparing the patient's plasma for compatibility testing is:
D. Autoadsorption using the patient's heat-eluted, enzyme-treated red cells.
A 40-year-old man with autoimmune hemolytic anemia with a specificity of auto anti-e has a hemoglobin level of 10.8gm/dL. The patient will most likely be treated with:
B. no transfusion
A patient presents to their physician with bluing of the hands and feet after cold exposure. The Physician orders blood work on the patient. Their hemoglobin is 10 g/dL with an elevated retic count. The DAT is positive with complement only. What is the most probable explanation for this?
Cold Autoantibody
Refer to the following data:
Hemoglobin 7.4g/dL
Retic count 22%
BS DAT 3+
IgG 3+
C3 0
SI 3+
SII 3+
Autocontrol 3+
Which clinical condition is consistent with the lab results given?
C. Warm autoimmune hemolytic anemia
(cold hemagglutinin disease - would see pos. complement C3; Penicillin-induced hemolytic anemia - would see negative screen; delayed transfusion reaction - would see weaker DAT)
A 50 year old man with autoimmune hemolytic anemia has been feeling tired. His Physician orders a hemoglobin that is reported at 10.8g/dL. This patient should be treated with:
A. Nothing - would hemolyze newly transfused cells
The drug cephalosporin can cause a positive direct coombs test by which mechanism?
The mechanism that best explains hemolytic anemia due to penicillin is:
D. drug adsorption
A 35 year old female with lupus is admitted to an inpatient unit. A type and screen is ordered. Both screen cells are 3+ at IAT. The most likely explanation is:
B. warm autoantibody
and
d. alloantibodies
Which of the following medications are most likely to cause the production of autoantibodies?
A. methyldopa
A patient has a negative antibody screen but their DAT is positive. The eluate is negative. The most likely drug involved is:
C. cephalothin
PCH is associated with which blood group?
B. P
Which is characteristic of anti-i?
A. found in serum of patients with infectious mono
In which situation is a red cell separation indicated?
C. recently transfused patient with alloantibodies
A patient has warm autoimmune hemolytic anemia and must be transfused immediately. What technique would you perform? The patient has no transfusion history.
C. autoadsorp patient's plasma with the has no transfusion history
A patient has cold autoimmune hemolytic anemia. A cold panel is performed at 4 degrees. The patient's plasma will react with:
A. all cells from the panel and his own cells
A 25 year old female is admitted to the ED and her type and screen results suggest she may have cold autoimmune hemolytic anemia. A DAT is performed. What is going to be detected?
D. C3d
A patient types:
Anti-A 3+, A1 cells 1+
Anti-B 0, B cells 4+
Anti-D 4+
SCI 3+, SCII 3+, DAT 3+
What do you suspect this discrepancy is due to?
a. A2 with anti-A1
b. Cold autoimmune hemolytic anemia
c. Warm autoimmune hemolytic anemia
d. Drug induced
a. A2 with anti-A1
b. Cold autoimmune hemolytic anemia
c. Warm autoimmune hemolytic anemia
A patient is admitted to the ED and is suffering from massive trauma. Blood is needed right away. The antibody screen is 3+ with both cells and the 6 units crossmatched are all 3+. What will you do?
Call lab director, run panel, perform a crossmatch
What is the definition of a hemolytic transfusion reaction?
the lyses or accelerated clearance of RBCs in the transfusion recipient due to immunologic incompatibility between donor and recipient.
What are some characteristics of intravascular hemolysis?
1. activated complement
2. hemoglobinemia/hemoglobinuria
3. DIC/renal failure
What are the symptoms of Intravascular hemolysis?
1. Fever, chills
2. back pain
3. hypotension
4. shock
5. hemoglobinuria
6. sense of impending doom
What are characteristics of extravascular hemolysis?
1. usually non-ABO
2. incomplete complement activation
3. no release of free hemoglobin
4. mild symptoms
5. fever, chills
6. increases serum bilirubin
7. by-stander hemolysis
8. cytokines implicated in hemolysis
9. cells destroyed in liver and spleen
What are some causes of hemolytic reactions?
1. clerical errors
2. ABO mismatch
What are causes of hemolyzed units?
1. improper temp/storage
2. mechanical malfunctions
3. incompatible solutions
4. bacterial growth
What factors contribute to hemolytic severity?
1. class and subclass of immunoglobulin
2. ability of antibody to activate complement
3. plasma concentration of antibody
4. amount of incompatible RBCs transfused
5. Condition of patient
What is the treatment for a hemolytic reaction?
Depends on severity but you want to maintain adequate renal blood flow and treat hypotension.
What is the definition of a Delayed Hemolytic Reaction?
Transfusion of an apparently well tolerated compatible unit of blood where the antibody is not detected at the time of transfusion producing a primary or secondary response.
What is a primary response regarding a delayed hemolytic reaction?
When a patient is transfused and builds an antibody 10-14 days after the transfusion. The antibody will react with positive donor cells.
Risk of alloimmunization is 1-1.6% for each RBC unit. Usually a mild reaction.
What is a secondary response regarding delayed hemolytic reactions?
When an antibody titer is detectable 3-7 days after transfusion
Transfusion of antigen positive unit stimulates the patient to produce more antibody.
DHTR is usually caused by anti-Jka, anti-E, anti-D, anti-C, anti-K, and anti-Fya.
What are signs and symptoms of a delayed hemolytic transfusion reaction?
1. Low hematocrit
2. Extravascular hemolysis
What is the action of the healthcare provider in the instance of a delayed hemolytic transfusion reaction?
1. Stop transfusion immediately
2. Notify Physician
3. Notify Blood Bank
4. Clerical Check
What are the clinical results after a DHTR?
1. Low hematocrit
2. Low hemoglobin
3. Increased bilirubin
4. Increased plasma bilirubin
5. Increased retics
What serological testing may be performed in the case of a hemolytic transfusion reaction?
DAT and antibody screen
What is the work up performed in the Blood Bank in case of an HTR?
1. Compare pre and post specimen for hemolysis
2. Clerical check
3. Perform DAT on post specimen
4. Perform ABO/Rh group and type on post specimen
5. Additional serological work (type and screen, crossmatch, ABO/Rh on donor unit, antibody panel, eluate, antigen screen)
The acute form of cold hemagglutinin disease is usually secondary to which disorders?
lymphoproliferative disorders such as lymphomas or mycoplasmal pneumonia.
When is the chronic form of cold hemagglutinin disease often seen?
In elderly patients with CLL or Waldenstrom's macroglobinemia
What autoantibody is usually indicated in cold hemagglutinin disease?
Anti-I. An IgM antibody of secondary hemolytic episodes that follow mycoplasma pneumonia infections.
What autoantibody is indicated in cold hemagglutinin disease during episodes involving Mono?
Anti-i
What is the prevalence of anti-i? During hemolytic episodes?
Anti-i is present 50% of the time but less than 1% have hemolytic episodes.
What are the features of cold agglutinin syndrome?
1. chronic anemia
2. hemoglobinemia/hemaglobinuria
3. jaundice
4. linked to temperature of climate
What are the laboratory findings during cold agglutinin syndrome?
1. Interferes with ABO testing. (Remedy by washing with saline at 37C; allow red top to clot at 37C; autoadsorp autoantibody prior to testing; prewarm; perform a titer).
2. Rh typing with monnoclonal reagents will usually give valid results.
3. Antibody screen depends on technique used.
During a transfusion of a patient with cold agglutinin syndrome, how is acute hemolysis treated?
Reduce patient by keeping them warm and use a blood warmer during transfusion. Otherwise, 50% of cells will be destroyed.
What are characteristics of paroxysomal cold hemoglobinria?
1. During PCH, IgG is a biphasic hemolysin that do not hemolyze while body temp is normal.
2. Upon exposure to cold, the autoantibody binds to RBCs.
3. As the patients body temp returns to normal, the antigen-antibody complexes fix complement and result in severe intravascular hemolysis.
What are thew laboratory findings of PCH?
1. antibody has anti-P specificity
2. Low crit
3. Reticulocytosis
4. Blood stained UA (hematuria)
Describe the Donath-Landsteiner test:
Used to determine PCH:
1. Two clotted specimens are drawn from patient
2. One at 37C
3. The other at 4C for 30min, then at 37C for 30min
4. Spin both tubes
What is the treatment for PCH?
1. With Chronic PCH, keep patient warm.
2. During acute PCH, it usually terminates with resolution of infection.
3. Transfusion is un-necessary unless hemolysis is severe.
How would you perform a serological investigation of PCH?
1. Keep specimen at 37C.
2. Make a saline suspension using warm saline.
3. Make sure reagents are room temp.
4. Eluate autoantibody of cells if needed to type.
5. Positive DAT - complement - no eluate
6. Do panels at different temps to establish thermal amplitude of antibody
7. Run cold autoadsorptions
8. Titer
What are the characteristics of a normal cold antibody?
1. Reactive <22C
2. No spontaneous agglutination
3. No clinical significance
4. DAT negative
What are the characteristics of a pathological cold antibody?
1. Reactive up to 32C
2. Spontaneous agglutination
3. Titer >1000
4. Causes AIHA
5. DAT positive
Which of the following is a characteristic of anti-i?
B. found in the serum of patients with infectious mononuclesis.
In the case of cold autoimmune hemolytic anemia, the patient's serum would most likely react 4+ at immediate spin with:
D. all cells of a group O cell panel and his own cells
Cold agglutinin syndrome is associated with an antibody specificity toward which of the following?
A. I (associated with cold agglutinin syndrome)
Which of the following is a characteristic of anti-i?
C. reacts best at room temperature or 4C
anti-i is an IgM antibody and reacts with cord cells and i adult cells. Not associated with HDFN since IgM does not cross the placenta.
An obstetrical patient has had 3 previous pregnancies. Her first baby was healthy, the second was jaundiced at birth and required an exchanged transfusion, while the third was stillborn. Which of the following is the most likely cause?
D. Rh incompatibility
What is an alloantibody?
An antibody made against a foreign antigen.
What is an autoantibody?
An antibody made against self-antigens. Occurs when the immune system malfunctions.
Define autoimmune hemolytic anemia (AIHA):
A type of autoimmune disease in which the autoantibody targets the red cell antigens.
Define autoimmune disease:
When an autoantibody is directed to destroy cells and tissue that carry the target antigen.
What is hemolytic anemia?
The destruction of red blood cells by hemolysis where
--compensated anemia is the result of red cell production equals destruction and
--uncompromised anemia is the inability of bone marrow to compensate red cell destruction. Hematocrit decreases.
What are the two categories of warm autoimmune hemolytic anemia?
1. Primary - idiopathic
2. Secondary - disorders associated with WAIHA
What are the two categories of cold agglutinin syndrome?
1. Primary - idiopathic
2. Secondary - due to Mycopasma pneumonia, Infectious Mono
What are the two categories of paroxyomal cold hemoglobinuria?
1. Primary - idiopathic
2. Secondary - due to syphilis or viral infections (measles, mumps)
What would the DAT result during AIHA?
negative
What disorders are frequently associated with WAIHA?
