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30 Cards in this Set
- Front
- Back
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During a routine type and screen, a patient typed as A positive. Three screening cell were 3+ positive. The 12-cell panel showed 3+ positivity for all cells tested. The direct
antiglobulin test was negative. These findings best describe: a. Auto antibody b. Multiple alloantibodies c. Antibody against high-frequency antigen d. Antibody against D antigen e. Nonspecific reaction |
c.
Antibody against a high frequency antigen may produce positive reactions in all tested red cells; however, the DAT test is always negative in these cases. |
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What is the most common complication of apheresis?
a. Fluid overload b. Air embolism c. Citrate toxicity d. TRALI e. Elevated blood pressure |
c. Citrate toxicity
is the most common side effect of plasmapheresis due to low plasma ionized calcium. |
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What is the most common replacement fluid for plasmapheresis performed for thrombotic thrombocytopenic purpura (TTP)?
a. Saline b. Plasma protein preparation c. Intravenous immunoglobulin (IVIG) d. 5% albumin e. Plasma |
d.
Plasma is the most common replacement fluid for TTP. FFP, 24-plasma, and thawed plasma can all be used. Plasma will remove high MW von Willebrand factor and ADAMTS13 inhibitor, and will increase the ADAMSTS13 level. |
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Red blood cell anticoagulant/preservative solutions contain all of the following EXCEPT:
a. Dextrose b. Adenine c. Monobasic sodium phosphate d. Calcium citrate e. Mannitol |
d. Calcium citrate
is not part of the additive in red cell preservative solutions. Sodium citrate is added as anticoagulant, phosphate salts function as buffer, dextrose, and mannitol as source of carbohydrate for energy production, and adenine as source for ATP. |
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Red blood cell anticoagulant/preservative solution AS (Adsol) permits storage for up to:
a. 21 days b. 28 days c. 35 days d. 42 days e. 49 days |
d.
The shelf life is 42 days for all new red cell preservative solutions including AS-1, AS-3. |
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During red cell storage all the following changes occur EXCEPT:
a. Decreased 2,3 diphosphoglycerate b. Increased plasma hemoglobin c. Decreased pH d. Increased ATP e. Increased serum potassium |
d.
During red cell storage, both ATP and 2,3 diphosoglycerate are decreased by red cells metabolism, pH is decreased due to H ion production, and plasma hemoglobin and potassium ions are elevated due to red cell hemolysis. |
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Which of the following statements correctly describes the hemoglobin-oxygen dissociation curve for red cells refrigeration stored for greater than two weeks?
a. The curve is shifted to the right. b. The curve is shifted to the left. c. There is no change in the position of the curve. d. The shape of the curve is changed from S (sigmoid) shape to Z shape. e. The shape of the curve is changed from Z shape to S (sigmoid) shape. |
b.
During red cells storage the red cells and the 2,3-diphosoglycerate concentration are reduced. The very low 2,3 DPG will shift the Hb-O association curve to the left. |
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Cryoprecipitated antihemophilic factor (AHF) is enriched with all of the following coagulant proteins EXCEPT:
a. Fibrinogen b. Von Willebrand factor c. Factor VIII d. Factor VII e. Factor XIII |
d.
Cryoprecipitated antihemophilic factor (AHF) is enriched with fibrogen, von Willebrand factor, factor VIII and factor XIII. Factor VII is present in low concentration in cryoprecipitate AHF. |
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When recombinant factor VIII is NOT available, what is an alternative blood product to treat a patient with factor VIII deficiency with a small joint hematoma?
a. Fresh whole blood b. Plasma-derived von Willebrand factor c. Cryo-depleted plasma d. Cryoprecipitate e. Fresh plasma |
d. Cryoprecipitate AHF
is rich in fibrinogen, von Willebrand factor, factor VIII, and factor XIII. |
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Thawed pooled cryoprecipitated AHF can be stored at room temperature for a maximum of:
a. 2 hours b. 4 hours c. 8 hours d. 12 hours e. 24 hours |
b.
Thawed Cryoprecipitate AHF will expire in 4 hours in an open system or pooled; 6 hours if thawed and not pooled. |
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All of the following statements about granulocyte product collected by apheresis are true EXCEPT:
a. It should be irradiated. b. It may be stored for up to 72 hours. c. It should be kept at room temperature. d. It should be stored with gentle agitation. P.286 e. It should be crossmatched with the recipient serum. |
b.
Apheresis granulocyte function is time-dependent. Phagocytic functions deteriorate with time and a unit becomes unuseful after 24 hours and may be discarded. |
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The antibody implicated in hemolytic disease of the newborn that is most likely to suppress fetal erythropoiesis is:
a. Anti-Fya antibodies b. Anti-Jkb antibodies c. Anti-D antibodies d. Anti-Rh 17 antibodies e. Anti-K0 antibodies |
e. Anti-Ko antibodies
are known to suppress fetal bone marrow, causing intrauterine and postpartum severe anemic. |
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Which of the following red cell antigens serves as a receptor for plasmodium vivax?
a. Jka and Jkb b. Lewis A and Lewis B c. P antigen d. Fya and Fyb e. Glycophorin A and B |
d.
Duffy antigens are receptors for plasmodium vivax. In Africa, most of population are Duffy negative due elimination of infected Duffy positive population. |
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All of the following are true for the anti-JKa and anti-JKb antibodies EXCEPT:
a. They may be missed if present in low titer. b. They have high affinity and high avidity. c. They require the presence of complement to detect. d. They may cause delayed hemolytic transfusion reaction. e. They are low frequency antigens and rarely cause hemolysis. |
e.
Anti-Kidd antibodies are high-affinity and highavidity antibodies. Roughly, 72% of whites are Jk(a+,b+) and their antibodies can cause moderate to severe hemolytic transfusion reaction. |
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All of the following are true for Lewis A and B antigen EXCEPT:
a. Lewis antigens are glycolipid antigens. b. Lewis antibodies are IgM isotype. c. Lewis antibodies do not cause hemolytic transfusion reactions. d. Lewis antigens are located at glycophorin A and B molecules. e. Lewis antigens are well developed in neonates. |
e.
The Lewis antigens are not developed in newborn and are not intrinsic to red cells but rather adsorbed from the plasma onto the red cell membranes and become expressed on glycosphingolipid type I chain. Lewis antibodies do not usually cause hemolysis. |
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What are the two most reliable laboratory findings to diagnose thrombotic thrombocytopenic purpura (TTP)?
a. Low neutrophil count - positive neutrophil antibody assay b. Low platelet count - positive anti-platelet antibody assay c. Anemia - positive direct antiglobulin test d. Low platelet count - low ADAMTS13 e. Low factor VIII activity-prolonged aPTT |
d.
Low platelets and low ADAMT13 are the most reliable findings in TTP. In addition, elevated LDH, low hematocrit, and presence of ADAMTS13 inhibitors are present in most cases of TTP. |
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The pathophysiology of thrombotic thrombocytopenic purpura is best described as resulting from:
a. Binding of red blood cells to endothelium b. Activation of complement system c. Activation of extrinsic coagulation pathway d. Formation of red cell thrombus e. Binding of platelets to HMW von Willebrand factor |
e.
The binding of high molecular weight von Willebrand factor to the platelet and forming platelet thrombus is the main pathology in TTP. |
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Which apheresis fluid is LEAST likely to improve the clinical course of TTP?
a. Only male plasma b. 50/50 plasma and 5% human serum albumin c. Cryo-poor plasma d. 5% human serum albumin e. Fresh frozen plasma |
d.
All plasma preparation may be used for apheresis of TTP including only male plasma which is collected only from male donors to prevent TRALI. Plasma will increase the level of ADAMTS13. Several studies showed that human serum albumin is not suitable replacement fluid for TTP treatment. |
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Transfusion-associated graft-versus-host disease (TAGVHD) has a worse outcome than bone marrow transplant-associated graft host disease (BMTAGVHD) because:
a. The cell type responsible for TAGVHD is T lymphocyte while in BMTAGVHD is B lymphocytes. b. The bone marrow hematopoietic trilineage is the main target in TAGVHD. c. The activation of dendritic cells is augmented in TAGVHD. d. Bone marrow transplant protects against GVHD. e. Bone marrow transplant patients receive intensive immunosuppression. |
b.
The exact cause for the severity of TAGVHD is not known. However, several publications supported the notion that the bone marrow hemopoietic trilineage cells may be the target for TAGVHD. |
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Transfusion-associated graft versus host disease may occur in all of the following disorders EXCEPT?
a. Hodgkin lymphoma b. Wiskott Aldrich syndrome c. IgA deficiency d. Patients treated with purine nucleoside analogs such as fludarabine and 2-cholrodeoxyadenosine (cladribine) e. Intrauterine red cell exchange |
c.
TAGVHD may develop in patients with cellular immunodeficiency (especially deficiency of T cells) and those receiving high doses of potent immunosuppressors. Patients with IgA deficiency have an intact immune system with deficiency of IgA production and will not develop transfusion-associated graft versus host disease. These patients do not require irradiated blood products. |
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The most appropriate measure to prevent transfusion-associated graft-versus-host disease from platelet is:
a. Wash using automated equipment. b. Filter using a leukoreduction filter. c. Irradiate using 25G. d. Use male only platelets. e. Use directed donor platelets. |
c.
The leukoreduction filter is not sufficient to remove all of the lymphocytes which can cause TAGFHD. Leukocyte-reduced blood products have efficient lymphocytes to cause TAGVHD. All other choices may also lead to TAGVHD except irradiation, which prevents proliferation of the donor lymphocytes. |
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The correct cell type responsible for transfusion-associated graft versus host disease in the animal model based on a number per kilogram is:
a. Lymphocytes b. Nucleated RBCs c. CD34 cells d. Monocytes e. Platelets |
a.
Donor T lymphocyte population is the cellular component responsible for TAGVHD. Lymphocyte number is implicated. |
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The correct agent or mechanism responsible for transfusion-related acute lung injury (TRALI) includes the following EXCEPT:
a. Presence of donor anti HLA class I antibodies in the recipient b. Presence of donor antigranulocytes antibodies in the recipient c. Presence of recipient antilymphocyte antibodies in the donor d. Presence of donor anti-HLA Class I and antigranulocyte antibody in the recipient e. Presence of recipient anti-HLA class II antibodies in donor. |
c.
Transfusion-related acute lung injury (TRALI) may be caused by agglutinating patient granulocytes with donor anti-HLA or white cell antibodies in the small pulmonary arterioles and capillaries. All the mentioned agents could cause the TRALI except donor lymphocyte antibodies. No study has shown that anti-lymphocyte antibodies are responsible for TRALI. |
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Platelets have all of the following antigens EXCEPT:
a. HLA class II antigens b. HLA class I antigens c. ABO antigens d.GPIIIb/IIa e. HPA-1 |
a.
Platelets carry ABO group and HLA class I antigens but not HLA class II antigens. HLA class II antigens are expressed on antigen presenting cells including B lymphocytes, monocytes/macrophages, dendritic cells, and activated T lymphocytes. |
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What is the best management strategy for a patient diagnosed with immune thrombocytopenic purpura (ITP) without mucosal bleeding?
a. Monoclonal antibody treatment b. Transfusion of leuko-reduced platelets c. Transfusion of irradiated platelets d. Immunosuppressive medications e. Plasmapheresis |
d.
ITP is treated with intravenous immunoglobulin (IVIG), immunosuppressors, or splenectomy. In 2008, the FDA approved recombinant platelets growth factor for treatment of ITP. |
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What is the most common antibody found in a neonate born with thrombocytopenia?
a. Anti-HPA-1 b. Anti-HPA-2 c. Anti-HPA-3 d. Anti-HLA class I e. Anti-HLA class II |
a. Anti-HPA-1a
is the most common antiplatelet antibodies in ITP. |
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Each of the following may be used in the treatment of ITP in a D negative (Rh negative) patient EXCEPT:
a. Corticosteroids b. IVIG c. Anti-D antibody d. Splenectomy e. DDAVP |
d.
Anti D antibody may be used to treat D positive patients and not D negative patients. Anti-D will bind to Rh D positive red cells; the coated cells will attract phagocytic cells and prevent the attack on platelets coated with antibody. |
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The indications for platelet transfusions include each of the following EXCEPT:
a. A nonbleeding patient with platelets less than 10,000/!l b. A nonbleeding, nonsurgical patient with platelet counts between 10,000 and 50,000/!l c. A bleeding patient with platelets less than 50,000/!l d. A bleeding patient with acute renal failure and platelets more than 50,000/!l e. A bleeding patient with Glanzmann thrombathenia with platelets of 200,000/!l |
b.
All of these conditions are indications for transfusion except non-bleeding patients with platelet count 20,000/!l or more. Several studies showed that 10,000/!l platelets have a reasonable haemostatic efficacy in non-bleeding patients. |
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The following criteria define a suitable blood donor EXCEPT:
a. Hemoglobin minimum of 12.5 g/dl b. Age more than 70 years c. History of jaundice before age of 11 d. Age of less than 18 years with parent consent e. Received a tattoo one month prior |
e.
All mentioned criteria are accepted for blood duties except tattoo done 1 month ago. For donor with recent tattoo, 12 months or more must relapsed before accepting the donor. There is no age limit for blood donation. |
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Which one of the following is an indication for blood donation deferral?
a. Return from traveling to a malaria endemic area less than a year ago b. Tattoo performed less than three weeks ago c. Receiving recombinant growth factor d. Receiving rabies vaccine within the last two weeks e. Receiving the flu vaccine two days ago |
c.
All the mentioned criteria cause donor deferral except receiving recombinant growth factor. Donors who in the past received animal source growth factor are permanently deferred. |
