HEMOTHERAPHY DECISIONS AND THIER OUTCOME / PLATELET AND GRANULOCYTE Ag AND Ab Flashcards
This refers to the development of severe anemia where the hemoglobin following transfusion is lower than that before a transfusion
Hyperhemolysis
Platelets are necessary for all of the following, but their primary role is in ________ ?
A. Immune response
B. Hemostasis
C. Cardiovascular disease
D. Inflammation
B. Hemostasis
Which of the following is not a symptom of hyper hemolysis?
A. Elevated indirect bilirubin
B. Elevated haptoglobin level
C. Elevated lactate dehydrogenase
D. Reduction of reticulocyte counts
B. Elevated haptoglobin level
haptoglobin levels are reduced. This is a laboratory evidence of hemolysis, including choices A an C
Which of the following is not used to treat hyper hemolysis?
A. RBC transfusion
B. Corticosteroids
C. Intravenous immunoglobulin (IVIG)
D. Avoidance of transfusion
A. RBC transfusion
Transfusion often exacerbates anemia and should be avoided
Which of the following morphological changes does NOT occur during RBC storage?
A. 2,3 diphosphoglycerate (DPG) levels decline
B. Free hemoglobin decreases
C. Free iron increases
D. Extracellular potassium increases
B. Free hemoglobin decreases
Free Hgb levels increase
This method is the preferred method for removing warm auto immune hemolytic antibodies (WAIHA) in patients who were not recently transfused.
Autologous adsorption
What is the recommended lower platelet count threshold for hospitalized patients?
10,000/ uL
What is the normal lifespan of platelets in circulation?
~ 8-10 days
What is the suggested platelet count for lumbar puncture and major electric elective nonneuroaxial surgery?
50,000/ uL
True or false - In bleeding patients with qualitative platelet dysfunctions, platelet transfusion may be inappropriate even with normal platelet counts
False.
It is appropriate to tx platelets
True or false - platelets do not express Rh antigens, but they do express ABH antigens.
True.
___________ is the consistent failure to achieve an appropriate platelet count increment following platelet transfusion
Platelet refractoriness
Which of the following is NOT a nonimmune cause of platelet refractories?
A. Sepsis B. Bleeding hypersplenism C. Disseminated intravascular coagulation (DIC) D. Drug effects E. HLA antibodies
E. HLA antibodies
Hypersplenism - aka splenomegaly
DIC - spontaneous formation of blood clots in blood vessels
What is a typical count for a apheresis platelet unit?
3 x 10 ^11
What is the expected one hour post platelet transfusion increment in a healthy recipient?
~ 30,000 - 60,000 / uL
Which antibodies are the most common cause of immune platelet refractories?
HLA antibodies
True or false - immune refractoriness due to HLA antibodies occurs in platelet transfusion recipients due to white blood cell contamination in the platelet unit rather than the platelets themselves.
True
What method is used to detect platelets HLA antibody?
Flow cytometry
What is the PRA (panel reactive antibody) threshold (%) for platelet refractoriness?
20%
Which of the following is the least best method to manage platelet immune refractoriness?
A. Platelet cross matching
B. Providing HLA matched platelets
C. Placing patient in platelet drip protocol
D. Identifying HLA antibody specificity
C. Placing patient in platelet drip protocol
True or false - Prophylactic plasma transfusion is necessary before an invasive procedure based on abnormal INR results in non-bleeding individuals.
False
Abnormalities in test results like the INR failed to predict bleeding in nonbleeding individuals; This practice exposes risks of plasma transfusion without providing real benefit
Which of the following is not an indication for Plasma transfusion?
A. Patients with liver disease B. Factor XI deficiency C. DIC D. All OF the above E. None of the above
D
Plasma transclusion is indicated in patients with coagulation deficiencies and to manage patients with specific protien deficiencies.
Which of the following is not a reversal method for the effects OF Warfarin?
A. Heparin infusion
B.PCCs
C. Vit K administration
D. Plasma
A. Heparin
Warfarin (given orally) and heparin (injection?) are both anticoagulants
Warfarin causes the deficiency of __________, an important compound in clotting formation, by inhibiting epoxide reductase, an enzyme that converts it in its reduced form.
Vitamin K
Warfarin which is structurally similar to vitamin K, competitively inhibits the epoxide reductases. Thus, warfarin intake causes a deficiency of reduced vitamin K, which in turn causes decreases in the functional activity of factor II (thrombin), VII and IX, as well as antithrombotic factors (protein C and S).
This is the preferred method (over plasma transfusion) for reversing the effects of Warfarin for patients who need it urgently.
Four- factor prothrombin complex concentrate (PCCs)
Which of the following is not found in PCCs?
A. Vit K B. Factor II C. Factor VII D. Protein S E. Factor X
A. Vit K
PCCs contain Factors II, VII, IX, and X in the nonactivated state, Proteins C and S. These factors have reduced functional activities in patients taking warfarin
This blood component is used in place of PCCs (for warfarin reversal) for patients who have heparin induced thrombocytopenia.
Plasma
Plasma is indicated in patients with heparin induced thrombocytopenia because some PCCs contain heparin
Enumerate the factors and proteins that are found in cryoprecipitate
Fibrinogen factor VIII (anti-hemophilic factor) von Willebrand factor fibronectin factor XIII (fibrin stabilizing factor)
Which of the following scenarios most likely does not indicate for cryoprecipitate transfusion?
A. Patients undergoing cardiac surgery with acquired hemostatic defects secondary to cardiopulmonary bypass
B. Patients with acquired hypofibrinogenemic condition undergoing liver transplantation
C. A pregnant woman who has a Fibrinogen concentrate level of about 6 g/L in her third trimester
D. Patient undergoing postpartum hemorrhage who had a fibrinogen concentration of about 1.5 g/L in her third trimester
C
Pregnancy is associated with an increase in fibrinogen concentration above the laboratory levels of normal which is approximately 6 g/L in the third trimester compared to 2 to 4 g/L in the nonpregnant state.
GRANULOCYTE components require the following in order to be transfused, except:
A. Be ABO compatible with patient
B. Irradiation
C. Stored at 1-6C
D. Transfused w/in 24 hrs of collection
C
Must be stored at room temperature
Which of the following is not an indication for GRANULOCYTE transfusion?
A. Patients with severe prolonged neutropenia
B. Neutropenic patients with fungal infections
C. Patients with granulocyte count of greater than 4x10^10
D. None of the above
C
There is no required granulocyte count range
A rare bleeding disorder caused by congenital absence or dysfuction of GPIIb/IIIa genes ITGA2B genes and/or ITGB3 genes
Glanzmann thrombasthenia
True or false - patients with Glanzmann Thromboasthemia who are exposed to normal platelets by transition or pregnancy can make iso antibodies against GPIIIb/IIIa
True
Patients with the diseas lack these plt antigens(GPIIIb/IIIa). This is most abundantly expressed in plt membrane making it highly immunogenic
This is the most common HPA-specific plt antibody detected in alloimmunized patients of European ancestry
Antibody against HPA-Ia (80%)
This low frequency platelet antigen ____________, which are also expressed in GPIIIa in plt membrane is more common in Japanese and Chinese ancestry
HPA-4b
This disease is caused by the deficiency of GPIb/V/IX complex in platelet receptors and is characterized by “giant platelets”, prologed bleeding time and thrombocytopenia
Bernard Soulier syndrome
This receptor complex forms the vWF receptor in platelets and is lacking in Bernard Soulier syndrome
GPIb/V/IX complex
____________ is a major collagen recpetor in platets; its proteins carry the HPA-5a/5b antigens.
Integrin GPIa/IIa
The second most common HPA antibody which targets the GPIa protein
Anti-HPA-5
True or false: Platelet monocytes/macrophages and nucleated erythrocytes are the ony blood cells that express GPIV/CD36
True
GPIV/ CD36 are class B scavenger receptor. They bind ligands like LDL cholesterols, thrombospondin, types I and IV collagen and malaria infected RBCs.
CD36 deficient individuals who have been exposed to normal platelets can produce antibodies to CD36 that have been reported to cause the ff, except:
A. TTP
B. PTP
C. FNAIT
D. Platelet refractoriness
A. TTP
What is the 1 hr post platelet- transfusion CCI value which defines platelet refractory state?
<5000 to 75000 /uL/m^2/10^11 platelets transfused after two consecutive transfusions adequately defines the refractory state
___________ is the most common immune cause of platelet refractoriness & can be diagnosed by the demonstration of significant levels of antibodies to Class I HLA in the serum.
HLA sensitization
Other causes: antibodies to HPA, ABO incompatibility, drug induced antibodies
Which of the ff is not an immune cause of platelet refractoriness?
A. TTP
B. Allogeneic transplantation and treatment
C. ABO incompatibility
D. Fever
C. ABO incompatibility
This may cause sensitization which lead to development of antibodies
Which of the ff is the best strategy for platelet selection for transfusion in patients with alloimmune refractoriness?
A. Platelet crossmatching
B. Determine the specificity of patient’s HLA antibody (Antibody specificity prediction)
C. Select “best-mismatch” units by estimating which antibodies the recipient is least likely to have
D. Supply apheresis platelets from donors whose HLA-A and -B antigens match those of the patient
E. Random selection of platelets
D. Supply apheresis platelets from donors whose HLA-A and -B antigens match those of the patient
Other strategies are ranked as follows:
2nd - C. Select best mismatched units
3rd - B . ASP
4th - A. Crossmatching
A syndrome involving immune destruction of fetal platelets by maternal antibodies
Fetal and neonatal alloimmune thrombocytopenia (FNAIT) - analogous to HDFN
Which of the ff is TRUE regarding FNAIT?
A. Newborn’s platelet antigens are inherited from the father
B. It causes severe thrombocytopenia
C. The IgG antibodies to fetal platelets crosses from maternal circulation into the placenta
D. All of the above
E. None of the above
D. All of the above
A syndrome characterized by the development of dramatic, sudden, and self limiting thrombocytopenia 5 to 10 days after a blood transfusion in HPA sensitized patients.
Post transfusion purpura
Which of the ff is the best, first line therapy for patients experiencing PTP for the first time?
A. Transfusion of washed platelets
B. Transfusion of antigen negative platelets
C. Administration of IVIG
D. Plasma exchange
C. Administration of IVIG
Which of the ff products should be transfused to patients who have recovered from PTP?
A. Washed platelets
B. Crossmatched platelets
C. Antigen negative platelets
D. Plasma
C. Antigen negative platelets
An immune platelet disorder in which autoantibodies are directed against platelet antigens resulting in platelet destruction.
Immune thrombocytopenia
Which of the ff about immune thrombocytopenia is false?
A. Females are twice as likely to be affected
B. Spontaneous remission are often common
C. IVIG is used as first line therapy
D. Acute ITP in children often occurs after viral infection
B. Spontaneous remission are often common - it is rare
This platelet antibody test is the most sensitive and specific in identifying HPA specificity of serum antibodies
A. Glycoprotein specific assays
B. HPA genotyping
C. Flow cytometry
D. Solid phase red cell adherence assay (SPRCA)
A. Glycoprotein specific assays
Which of the ff statements regrding drug induced antibodies that causes thrombocytopenia is correct?
A. Non-drug induced antibodies need the presence of drugs in the system to be reactive
B. These antibodies causes rapid onset of thrombocytopenia that usually results after a few hours after drug discontinuation
C. Nondrug dependent antibodies are serologically indistinguishable from other platelet antibodies
D. These antibodies that are formed are usually drug dependent
C. Nondrug dependent antibodies are serologically indistinguishable from other platelet antibodies
B. - thrombocytopenia usually resolves 3-4 days after discontinuation
D. - both nondrug and drug dependent are formed
Which of the following test methods is used to test for platelet antibodies in patients with ITP?
A. Flow cytometry
B. Solid phase, glycoprotein specific assay
C. ELISA
D. Genotyping
B. Solid phase, glycoprotein specific assay
Which of the following test methods is used to test for platelet antibodies in patients with drug dependent antibodies?
A. Flow cytometry
B. Solid phase, glycoprotein specific assay
C. ELISA
D. Serologic testing
D. Serologic testing
A neutrophil disorder that is caused by maternal antibodies against the antigens of fetal neutrophils.
Neonatal alloimmune neutropenia (NAN)
A transfusion reaction that is acute, characterized by respiratory distress occuring within 6 hrs of transfusion.
TRALI
Which of the ff is not a characteristic of TRALI?
A. Hypotension
B. Hypertension
C. Pulmonary edema
D. Fever
B. Hypertension
Which of the ff is usually involved in TRALI?
A. Neutrophils
B. Drug sensitization
C. Granulocytes
D. Platele autoantibodies
A. Neutrophils
In severe TRALI, causative antibodies are most often found in the plasma blood donors. When these antibodies are transfuse, they cause activation of prime neutrophils that are sequestered in the lungs of certain patients. The activated neutrophils undergo oxidative first releasing toxic substances that damage pulmonary endothelium and resulting in capillary leak and pulmonary edema
True or false - Granulocyte antibody testing is usually a high throughput test.
False. Usually testing is not readily available an is time consuming
