7: RBCs And Bleeding Disorders

Question 1

What does hematocrit measure?

Answer 1

% of whole blood volume occupied by RBCs

Question 2

What does low vs high MCV mean?

Answer 2

Microcytic vs macrocytic anemia

Question 3

What does low MCH mean?

Answer 3

Hypochromic RBCs

Question 4

Reticulocytes appearance on histo slides

Answer 4

Polychromatic with purple-grey tinge in larger cells; supravital stain highlights presence of RNA in immature cells

Question 5

Anisocytosis

Answer 5

Increased RDW -RBCs are different sizes

Question 6

Why is chronic blood loss anemia a subtle presentation?

Answer 6

Gradual blood loss causes compensation over time

Question 7

Two common themes in hemolytic anemia

Answer 7

1. Peripheral destruction of RBCs

2. BM attempts to compensate

Question 8

How to test for HS

Answer 8

Direct membrane tests (EMA and OFT)

Question 9

What can parvovirus cause in pts with HS

Answer 9

Aplastic crisis (can happen in any condition with over dependence on erythropoeisis)

Question 10

What infection has a common distribution with G6PD deficiency genes

Answer 10

Plasmodium falciparum

Question 11

Sickle cell trait

Answer 11

Heterozygous for the sickle cell gene -> minor sx

Question 12

Lab thing to dx sickle cell anemia

Answer 12

Hb electrophoresis

Question 13

Histo of cells with SC disease (sickle cell trait)

Answer 13

Target cells, not really true sickle cells

Question 14

Poikilocytes

Answer 14

Abnormally shaped cells

Question 15

Three ways to treat sickle cell

Answer 15

1. Hydroxyurea: increases Hb F
2. Supportive care
3. CRISPR

Question 16

What other anemia is confused with B-thalassemia minor

Answer 16

Iron deficiency anemia

Question 17

How to treat paroxysmal nocturnal Hemoglobinuria + the mechanism

Answer 17

Eculizamab: blocks C5 -> C5a -> no MAC

Question 18

Downside of Eculizamab treatment for PNH

Answer 18

Immune deficiency -> Neisseria infections

Question 19

Three stages of Fe deficiency + how much Ferritin in serum + sx

Answer 19

1. Reduced ferritin: ferritin <50 -> sx start
2. Iron deficiency: ferritin <30, sx accelerate
3. Iron Deficiency Anemia: Fe <12 mcg/L -> classic anemia sx

Question 20

Two drugs that commonly cause aplastic anemia

Answer 20

1. Chemotherapy (intentionally)

2. Chlorampheticol (accidentally)

Question 21

Labs to assess for vessel wall abnormalities

Answer 21

Not any really

Question 22

Examples of vessel wall disorders

Answer 22

1. Senile purpura (loss of CT around vessels)
2. Infection
3. Drug rxn
4. Scurvy/Ehler’s Danlos
5. Excess corticosteroid (Cushing)
6. Henoch-schonlein purpura
7. Heridary hemorrhagic telangiectasia
8. Perivascular amyloid

Question 23

Perivascular amyloid in myeloma

Answer 23

Perivascular myeloid deposition -> raccoon eyes

Question 24

Value that is technically thrombocytopenia vs when sx occur vs when dangerous spontaneous bleeds occur

Answer 24

1. Technically: <150,000/uL
2. Sx at: <50,000/uL
3. dangerous bleeds: <20,000/uL

Question 25

Three drugs that cause drug-induced immune thrombocytopenia

Answer 25

Quinidine, vancomycin, heparin

Question 26

HITT mechanism

Answer 26

PF4-Heparin induces an Ab-mediated immune response against platelets

Question 27

Three ways to treat ITP

Answer 27

1. Corticosteroids 2. IV Ig 3. Rituximab: anti-CD20

Question 28

What does MAHA stand for?

Answer 28

Microangiopathic hemolytic anemia

Question 29

TTP therapy + its two mechanisms

Answer 29

Plasma exchange therapy: takes away multimers and Abs + provides ADAMTS

Question 30

HUS: supportive therapy is sufficient or not?

Answer 30

Yes - it often leads to fill remission

Question 31

Five types of bleeding disorders due to defective platelet function

Answer 31

1. Bernard Soulier: no adhesion 2. Glanzmann thrombasthenia: no aggregation 3. storage pool disorders: no granule release 4. Aspirin-induced 5. Uremia-induced

Question 32

Presentation of a platelet disorder vs a coagulation disorder

Answer 32

1. Platelet: mucosal bleeding, petechiae, small superficial bruises, bleeding after minor cuts 2. Coagulation: deep soft tissue bleeds, large deep bruises, hemarthroses, delayed bleeds after cuts

Question 33

Three ways to avoid infected blood products from donors?

Answer 33

1. Donor screening: HIV, hep 2. Test blood products: many different viruses 3. Store properly

Question 34

Why is it not that risky to not test blood products for bacterial infection?

Answer 34

If pt has bacterial infection in blood, they likely dont feel well enough to come donate blood

Question 35

How to prevent anaphylaxis in a pt being transfused who has IgA deficiency

Answer 35

Red cell washing