Heme/Onc 1 (Anemias)

Question 1

4 causes of Microcytic Anemia?

Answer 1

• Iron deficiency
• Thalassemia
• Sideroblastic anemia (can also be macrocytic)
• Anemia of chronic disease

Question 2

How to treat severe anemia?

Answer 2

Packed red blood cells

Question 3

At what point do you transfuse a patient w/ anemia (via giving packed RBCs)?

Answer 3

• if they are symptomatic (SOB, light-headed, syncope, hypotension, tachycardia, CP)
• if the hematocrit is very low (i.e. 25-30) in an elderly patient or a patient w/ heart disease

Question 4

What do you use to transfuse a IgA deficient patient?

Answer 4

IgA deficient donor FFP

Question 5

What are packed RBCs?

Answer 5

Concentrated blood, it is a unit of whole blood w/ 150mL of plasma removed
- Hematocrit = 70-80% (double normal)

Question 6

How much should each unit of PRBCs raise the hematocrit?

Answer 6

~ 3 points/unit

Question 7

When is Fresh Frozen Plasma used?

Answer 7

Replaces clotting factors in those w/ elevated PT, aPTT, or INR & bleeding
- used as replacement w/ plasmapheresis

(NOT used for hemophilia A/B or vWD)

Question 8

What is Cryoprecipitate used for?

Answer 8

Used to replace Fibrinogen & has some utility in DIC

• has high levels of clotting factors in smaller plasma volume
• high levels of Factor 8 & vWF

(basically this is never used first for anything)

Question 9

Whole blood is divided into what 2 products?

Answer 9

PRBCs & FFP

Question 10

Type of anemia?

Alcoholic w/ microcytic anemia

Answer 10

Sideroblastic anemia

Question 11

Type of anemia?

Rheumatoid arthritis patient w/ microcytic anemia

Answer 11

Anemia of Chronic Disease

Question 12

Type of anemia?

Asymptomatic patient w/ microcytic anemia

Answer 12

Thalassemia (trait)

Question 13

Specific lab findings for iron deficiency anemia?

Answer 13

Microcytic anemia + Low Ferritin

• High TIBC
• High RDW (newer cells iron deficient & smaller)
• Elevated platelet count

Question 14

Formula for Transferrin saturation?

Answer 14

Iron divided by TIBC

Question 15

Microcytic anemia - best initial test?

Answer 15

Iron studies

- low ferritin = iron deficiency, low TIBC = Chronic disease, high iron = Sideroblastic

Question 16

Specific lab findings for Anemia of Chronic Disease?

Answer 16

Microcytic anemia + Low TIBC

• High ferritin
• Low serum iron

Question 17

Specific lab findings for Sideroblastic Anemia?

Answer 17

Microcytic anemia + Elevated Iron

• Ringed sideroblasts w/ Prussian blue staining
• Basophilic stippling

Question 18

Which microcytic anemia has normal iron studies?

Answer 18

Thalassemia

Question 19

Specific lab findings for Thalassemia?

Answer 19

Microcytic anemia w/ normal iron studies

Question 20

Sideroblastic anemia – Most accurate test?

Answer 20

Prussian blue staining for ringed sideroblasts

Question 21

Iron deficiency anemia – most accurate test?

Answer 21

Bone marrow biopsy for stainable iron

RARELY done

Question 22

Thalassemia – most accurate test?

Answer 22

Hemoglobin electrophoresis

Question 23

Bleeding disorders: 1st step?

Answer 23

Det. if related to platelets or clotting factors

Platelets: Superficial (epistaxis, gingival, petechiae, purpura, mucosal surfaces such as the gums, vaginal bleeding

CFs: Deep (Joints & Muscles)

Question 24

Immune Thrombocytopenic Purpura (ITP) – presentation?

Answer 24

• Isolated thrombocytopenia (normal hematocrit & WBC count)
• Normal-sized spleen

(Ex: 23-yr old woman w/ markedly increased menstrual bleeding & bleeding gums when she brushes her teeth, & petechiae on physical exam)

Question 25

ITP: | Mild bleeding w/ platelet count between 10,000-30,000 --- Tx?

Answer 25

Glucocorticoids | Prednisone

Question 26

``` ITP: Severe bleeding (GI/CNS) w/ platelet count < 10,000 --- Tx? ```

Answer 26

IVIG, anti-Rho (anti-D)

Question 27

ITP -- when to undergo splenectomy?

Answer 27

Recurrent episodes of bleeding, steroid dependent

Question 28

ITP -- Tx if splenectomy or steroids not effective?

Answer 28

Romiplostim or Eltrombopag, Rituximab, Azathioprine, Cyclosporine, Mycophenolate

Question 29

ITP: | Before splenectomy, give vaccination to what organisms?

Answer 29

- Neisseria meningitidis - Haemophilus influenzae - Pneumococcus

Question 30

What is Romiplostim?

Answer 30

Synthetic thrombopoetin for ITP

Question 31

What is Eltrombopag?

Answer 31

Synthetic thrombopoetin for ITP

Question 32

vWD -- AR or AD?

Answer 32

Autosomal Dominant

Question 33

vWD -- Dx tests?

Answer 33

- vWF (antigen) level may be dec'd - Ristocetin cofactor assay (detects vWF dysfx) - Factor 8 activity - Bleeding time (inc'd duration -- rarely done)

Question 34

vWD -- best initial Tx?

Answer 34

DDAVP (Desmopressin) -- releases subendothelial stores of vWF - if no response, use factor 8 replacement or vWF concentrate

Question 35

DIC -- what type of bleeding?

Answer 35

Bleeding related to both clotting factor deficiency & thrombocytopenia

Question 36

Most common hyper-coagulable state?

Answer 36

Factor V Leiden mutation

Question 37

Factor V Leiden mutation -- Tx?

Answer 37

Warfarin to an INR of 2-3 for 6 months

Question 38

When & how does HIT present?

Answer 38

5-10 days after the start of Heparin w/ a marked drop in platelet count (~30%) - Venous & arterial thromboses (clots) - rarely leads to bleeding (platelets just precipitate out)

Question 39

HIT -- Dx?

Answer 39

Confirmed w/ ELISA for platelet factor 4 (PF4) antibodies or the serotonin release assay

Question 40

HIT -- Tx?

Answer 40

- Stop all Heparin products - Give DTIs: Argatroban, Lepirudin, Bivalirudin - Give Warfarin AFTER using a DTI

Question 41

Name 3 Direct Thrombin Inhibitors

Answer 41

Argatroban, Lepirudin, Bivalirudin

Question 42

What is the only cause of Thrombophilia w/ an abnormality in aPTT?

Answer 42

Antiphospholipid Syndrome

Question 43

Antiphospholipid Syndrome -- best initial & most accurate test?

Answer 43

Best initial = Mixing study (aPTT remains elevated) Most accurate = Russell Viper Venom test (for lupus anticoagulant)

Question 44

2 types of Antiphospholipid Syndrome?

Answer 44

Lupus anticoagulant & Anticardiolipin antibody - both cause thrombosis - Anticardiolipin antibodies are ass'd w/ multiple spontaneous abortions

Question 45

3 molecules that normally promote platelet aggregation?

Answer 45

Thromboxane A2 --platelet activator & vasoconstrictor (synthesized from arachidonic acid w/in platelets) ADP -- powerful inducer of platelet aggregation 5-HT (serotonin) -- stimulates aggregation & vasoconstriction

Question 46

When platelets are activated, the _____ receptor binds fibrinogen, which cross-links adjacent platelets, resulting in aggregation & formation of a platelet plug.

Answer 46

GP 2b/3a

Question 47

ITP -- mechanism?

Answer 47

Autoimmune production of IgG against platelet antigens (i.e. GP2b/3a) - - autoantibodies are produced by plasma cells in the spleen - - antibody-bound platelets are consumed by splenic macrophages, resulting in thrombocytopenia

Question 48

Most common cause of thrombocytopenia in children & adults?

Answer 48

ITP

Question 49

How do Proteins C & S exert their anticlotting effects?

Answer 49

They inactivate factors Va & VIIIa (via proteolysis)

Question 50

Heparin -- MOA?

Answer 50

- Cofactor for the activation of Antithrombin - Inhibits effects of Factors Xa & IIa (thrombin) (whereas Warfarin affects "synthesis" of factors 2, 7, 9, 10 & Protein C & S)

Question 51

Arterial vs. Venous clots -- which are more fibrin-rich vs. platelet rich?

Answer 51

Arterial clots = platelet rich Venous clots = fibrin rich **though both are mixed

Question 52

Most common cause of inherited hyper coagulability?

Answer 52

Factor V Leiden -- mutant factor V that is resistant to degradation by activated Protein C

Question 53

Difference btwn unfractionated & LMW Heparin in their MOA?

Answer 53

- Both activate Antithrombin & enhance its inactivation of Factor Xa - Unfractionated Heparin and to a lesser-extent, LMWH, also enhances Antithrombin's inactivation of Thrombin

Question 54

Fondaparinux -- MOA?

Answer 54

Antithrombin activator (same as LMW Heparin)

Question 55

Rivaroxaban & Apixaban -- MOA

Answer 55

Direct Factor Xa inhibitors - given PO - do NOT require monitoring - 1/2-life = 10 hrs